View
0
Download
0
Category
Preview:
Citation preview
1
22nd Environmental Engineering and Science Symposium__________________________________________________________
April 7, 2015
Department of Civil and Environmental Engineering
2
3
Podium
Katherine A Stephens
Elucidating the role of anaerobic digestion of swine manure in nutrient and energy flows on
smallholder farms
In light of limited achievements in the United Nations (UN) 2015 Millennium Development Goal (MDG)
targeting environmental sustainability, there is a call to take more integrated approaches to developing
world interventions. This study proposes that viewing waste as a resource has the potential to affect
several factors underlying systemic poverty. Anaerobic digestion (AD) is an established sanitation
technology commonly applied in developed countries, which converts human or animal waste into: (1)
biogas, a clean form of household energy for both cooking and lighting, and (2) digestate, a stabilized
solid with bioavailable nutrients, which can be land applied as a biologically safe fertilizer. Although AD
has been tried in many parts of Sub-Saharan Africa (SSA), successful installations are sparse as
digesters have had mixed results in terms of biogas production and overall performance. Beyond
operational and infrastructural challenges, this lack of sustained adoption may partly stem from a lack of
information surrounding how animal waste differs in industrialized and developing countries (stemming
from very different animal diets), and how these differences influence AD performance. The present study
aims to characterize pig waste in SSA through critical literature review, and to identify potential solutions
to overcome barriers to wide scale application as an AD feedstock in SSA.
Justin Hutchison
Biocatalytic Perchlorate Reduction in Groundwater
Biocatalysts can target contaminants with specificity and high activity, as the biocatalysts have been
honed through evolution making them more efficient than the chemical and physical processes typically
used. The model contaminant, perchlorate, was selected as the focus of this research due to its stability
in aqueous environments, widespread contamination in the United States, and health risks. The
biocatalysts mimic the whole-cell biological process using perchlorate-reducing enzymes, perchlorate
reductase and chlorite dismutase, which can reduce perchlorate to innocuous chloride and molecular
oxygen. Biocatalysts were assayed in two groundwater sources from Iowa and Illinois. Biocatalysts
achieved maximum activity rates of 162.5 U/µg Mo in a buffered system and maintained robust
perchlorate degradation in groundwater, with maximum activity rates of 94% in Iowa GW and 82% in
Illinois GW as compared to buffered values. The biocatalysts were active over a range of temperatures
4
and pHs and had preferential activity for perchlorate. Alone, practical electrons donors such as acetate
resulted in no observed reduction of perchlorate. However, with the addition of an electron shuttle,
ascorbic acid in a 5:1 molar ratio resulted in 32.1% reduction of perchlorate in the presence of oxygen.
This work demonstrated the potential for biocatalytic treatment of perchlorate in groundwater over a range
of concentrations corresponding to those found in drinking water sources to those at sites with industrial
and military contamination with minimal interference observed from the groundwater matrix.
Artin Laleian
A hybrid pore-scale and continuum-scale model for biofilm growth in porous media
Subsurface pore structure is altered by the presence of biofilm, affecting solute transport within the
porous medium. While pore-scale numerical models capture these important dynamics, they are
computationally expensive, making them infeasible for large domains, or when details of the pore
geometry are unknown. In some applications, such as modeling groundwater contaminant plumes, hybrid
models may effectively reduce computational expense while preserving accuracy. Because most reaction
occurs along the plume fringe, this region is resolved at the pore-scale with a fine grid spacing. Away
from the mixing zone, a continuum approximation is sufficient and less computationally intensive. We
present a hybrid two-dimensional model for biofilm growth in which the pore-scale and continuum-scale
velocity fields are determined with lattice Boltzmann and finite volume methods, respectively, the solute
concentration field is determined with a finite difference method, solute utilization is determined by dual
Monod kinetics, and biofilm spreading is determined by a cellular automaton method. A mortar space
method is employed on subdomain boundaries to ensure continuity of fluid and solute mass. We find the
hybrid model has a significantly reduced CPU run time relative to a complete pore-scale model, while
producing a consistent result in terms of solute utilization and biofilm accumulation.
Srinidhi Balasubramanian
Developing Chemical Transport Model Ready Emissions for Predictions of Regional Air Quality
Trends
Chemical Transport Models (CTMs) are widely used to assess impacts of emissions of air pollutants on
regional air quality. Accurate emission inventories are central to developing accurate CTM predictions.
For the United States (U.S.), annual, county-scale emissions are available from the National Emissions
Inventory (NEI). Additional efforts are required to make these emissions CTM-ready at higher spatial and
5
temporal resolutions by using an emissions processor like the Spare Matrix Operator Kernel Emissions
(SMOKE) model. This presentation will provide an overview of the sources and trends in air pollutant
emissions in the U.S. for the year 2011 and an effort to use the NEI-SMOKE approach for a study aimed
at understanding the impact of NH3 emissions from fertilizer usage on ambient particulate matter
formation and deposition of reactive nitrogen in the Midwest U.S.
Within SMOKE, emissions are allocated to spatial resolutions (4 km x 4 km to 32 km x 32 km) required by
CTMs using spatial surrogates. Emissions are then allocated to the hourly scale based on temporal
factors that identify seasonality in emissions. Chemical speciation profiles are applied to account for
transformation of precursor pollutants. Emissions related to area, non-road and point sources are
obtained from NEI, while emissions from mobile and biogenic sources are dynamically estimated within
SMOKE. The NEI-SMOKE approach in developing CTM-ready emission inputs is advantageous as
emission inputs and ancillary data such as spatial surrogates and temporal factors are available through
the U.S. Environmental Protection Agency. Challenges however include paucity in emissions data for
some years, cumbersome efforts for processing spatial surrogates and computational time needed for
annual simulations. The NEI-SMOKE approach will be integrated with previous efforts that resulted in
improved ammonia emission predictions from fertilizer usage to support improved predictions of air
quality and deposition of reactive nitrogen in the Midwest U.S.
Raul Tenorio
Photogeneration of reactive oxygen species (ROS) by extracellular organic matter (EOM) in
Chlamydomonas reinhardtii photobioreactor cultures
Algal technologies have shown promise as tertiary wastewater treatment processes capable of reducing
nitrogen and phosphorous to meet increasingly stringent regulatory limits. Past research has shown that
irradiation of green microalgae under UV and visible light promotes enhanced transformation of trace
organic contaminants (e.g., PPCPs) compared to direct photolysis alone. The detection of singlet oxygen
(1O2) and hydroxyl radicals (•OH) in irradiated microalgae suspensions has lead researchers to believe
reactive oxygen species (ROS) generation is the source of the enhanced contaminant degradation.
Microalgae excrete extracellular organic matter (EOM) as metabolic byproducts that can act as
photosensitizers for ROS generation via similar mechanisms reported for dissolved organic matter (DOM)
derived from decayed terrestrial organic matter. This presentation will report on measurements of ROS
production in solutions of EOM extracted from pure batch cultures of C. reinhardtii. Results show
increasing steady-state levels of excited triplet dissolved organic matter (3DOM), singlet oxygen, and
production of hydroxyl radicals under sunlight irradiation as biomass grows and EOM levels in the culture
increase. Changes in ROS were compared with changes in culture characteristics such as volatile
6
suspended solids (VSS) and nutrient availability as well as EOM properties, including dissolved organic
carbon (DOC) and specific UV absorbance (SUVA254). EOM-sensitized ROS production in comparison
to other DOM sources will also be discussed along with implications for the fate of trace contaminants in
microalgae wastewater treatment systems.
Na Kyung Kim
Enrichment and characterization of microbial consortia degrading soluble microbial products
discharged from anaerobic methanogenic bioreactors
Soluble microbial products (SMP) produced in bioprocesses have been known as a main cause to lower
effluent quality and promote membrane fouling in water reclamation plants. In this study, a down-flow
hanging sponge (DHS) reactor was configured as a post-treatment process of anaerobic reactors to
biologically degrade SMP discharged from anaerobic reactors treating soft drink wastewater. The DHS
could successfully enrich microbial consortia and degrade SMP produced from the anaerobic reactors as
a sole substrate for a period >800 days. The microbial community composition and structure were
characterized using bacterial 16S rRNA gene pyrosequencing technology, and their correlation with
operational factors, such as hydraulic retention time (HRT), organic loading rate (OLR), and reactor
depths, was evaluated by performing redundancy analysis (RDA). On average, 68.9 to 87.5% SMP in
terms of soluble chemical oxygen demand (SCOD) was removed by the DHS reactor. Molecular weight
(MW) characterization by high performance liquid chromatography–size exclusion chromatography
revealed that a bimodal distribution of SMP with MW distribution of 13-17 kDa and <4 kDa was detected
in the influent of the DHS reactor. Between these two types of SMP, the small MW SMP were readily
degraded in the upper part of the reactor, whereas the large MW SMP were partially degraded in the
reactor. RDA of the microbial community at different phases and reactor depths showed that unclassified
Flavobacteria (25.9% in Phase V) and Saprospiraceae (30.1% in Phase V) were strongly correlated to
OLR, suggesting their active involvement in SMP removal. Different microbial diversity along with the
depth of the reactor implies that stratified microbial communities could participate in the process of SMP
degradation. Taken together, these observations indicate that biodegradation of SMP by selectively
enriched microbial community in the DHS reactor was effective enough to be incorporated as a strategy
controlling SMP for water reclamation systems.
Wangki Yuen
7
Ambient Plume Opacity Measurements Using a Video Camera Recorder and Digital Optical
Method
The applicability of Digital Optical Method (DOM) to measure plume opacity with a digital video camera
recorder (camcorder) in a smokestack was tested. Camcorders have the advantage of obtaining real-time
digital images, thus allowing continuous measurement of plume opacity and its temporal variation. They
also allow keeping an archival record of plume opacity events. A Canon camcorder was first calibrated
using two methods: by either varying the exposure value compensation of the camcorder, or varying the
radiance of a surface. The camcorder was then used in the field in July 9, 2013 to measure plume
opacity. A smoke generator was used that provided plumes of controlled opacity values. Opacity was
measured with a transmissometer inside the smoke generator stack. These opacity measurements were
used as the standard for testing the applicability of DOM for the camcorder to determine plume opacity.
Measurements were made during daytime and nighttime. Still images were extracted once every two
minutes for the entire videos and every second for select one minute periods to test this system at
different time resolutions. Each image was analyzed using DOM analysis software. Daytime results from
images obtained every two minutes show that camcorder derived opacity values have an average
absolute bias of 3.4% for black plumes and 5.1% for white plumes. Camcorder opacity measurements at
one-second time resolution have an average absolute bias <6% for black plumes and <4% for white
plumes. Nighttime results show that camcorder opacity values for black plumes have average absolute
bias of 3.2% at low opacity (<45%), but consistently lower than transmissometer values by an average
absolute bias of 16.5% at high opacity (>65%). These results demonstrate that camcorder can be used
for measuring plume opacity continuously during daytime, while nighttime measurements need further
investigation on the effect of surrounding lighting conditions.
Tianye Sun
Use of Historical Measurements to Constrain Black Carbon Emission Inventory of the United
States from 1960s to 2000s
We use historical coefficient of haze measurements in California and New Jersey to constrain the black
carbon (BC) emission inventory for 1960s-2000s. We study the relationship between emissions and
ambient air concentrations of BC using the Community Atmosphere Model. When formulating the
relationship into matrices that allow reconstruction of ambient concentration with emission inventory, we
account for the error in model meteorology and adjust it with measurements from NASA. We also apply
Heating Degree Days (HDDs) data to estimate seasonal variation in emissions, as observed from the
concentrations. However, HDDs does not fully explain the seasonal variation trend of the measurement.
8
Potential errors in historical emissions are identified by analyzing discrepancy between reconstructed and
measured BC. Acknowledging the resolution difference between the reconstructed concentrations based
on global model simulation and and the urban measurements, we rely more on the discrepancies in
trends than that in absolute discrepancies. We find that the magnitude of observations was decreasing
throughout this period of time, while the reconstructed concentrations peaked in the 1980s. The fuel uses
and emission factors for each technology division and sector of BC emission inventory in SPEW
(Speciated Pollutant Emissions Wizard) are analyzed to address the error indication from the
measurements. A modified emission inventory for the period 1960-2000 is presented.
Cheryl Weyant
Black Carbon Emissions from Associated Natural Gas Flaring
Approximately 150 billion cubic meters (BCM) of associated natural gas is flared and vented in the world,
annually, emitting greenhouse gases and other pollutants with no energy benefit. Based on estimates
from satellite observations, the United States flares about 7 BCM of gas, annually (the 5th highest flaring
volume worldwide). The volume of gas flared in the US is growing, largely due to flaring in the Bakken
formation in North Dakota.
Black carbon (BC), a combustion by-product from gas flaring, is a short-term climate pollutant that
absorbs shortwave radiation both in the atmosphere and on snow and ice surfaces. Flaring may be a
significant source of global BC climate effects. For example, modeling estimates suggest that associated
gas flares are the source of a significant percentage of BC surface concentrations in the Arctic, where
BC-induced ice melting occurs. However, there are no direct field measurements of BC emission factors
from associated gas flares. Emission measurements of BC that include a range of flaring conditions are
needed to ascertain the magnitude of BC emissions from this source.
Over one hundred flare plumes were sampled in the Bakken formation using a small aircraft. Methane,
carbon dioxide, and BC were measured simultaneously, allowing the calculation of BC mass emission
factors using the carbon balance method. BC was measured using two methods; optical absorption was
measured using a Particle Soot Absorption Photometer (PSAP) and BC particle number and mass
concentrations were measured with a Single Particle Soot Photometer (SP2). Simultaneous sampling of
BC absorption and mass allows for the calculation of the BC mass absorption cross-section.
Results indicate that emission factor variability between flares in the region is significant; there are two
orders of magnitude variation in the BC emission factors.
Yun Shen
9
Effects of continuous exposure to chlorination on mechanical and structural properties of
simulated drinking water biofilm
Biofilms, ubiquitous in drinking water distribution system (DWDS), could deteriorate drinking water quality
by hosting and releasing pathogens. USEPA required residual chlorine in DWDS to control the biofilms.
For improving the current knowledge of biofilm disinfection mechanisms in DWDS, the mechanical and
structural change of biofilms during long-term exposure of disinfectant was investigated. Biofilms used in
this study were developed from groundwater on PVC surfaces. After one year of growing period, these
biofilms were exposed to 4 mg/L of monochloramine or free chlorine under both hydraulic shearing and
static conditions, respectively. Atomic force microscope (AFM) and optical coherence tomography (OCT)
was used to determine the elasticity and structure. After 1 month of disinfectant exposure made the
biofilm surface became 2~7 times less elastic comparing with biofilms before disinfection. However, by
continuously exposing the biofilms to disinfectant for longer time, the elasticity of biofilms was recovered
to 1~3 times less elastic comparing with biofilms without treatment. OCT results did not show obvious
removal of biofilms under disinfectant exposure under all the experimental conditions. Under static
conditions, biofilms still kept same thickness and roughness with exposure of disinfectant. Under
hydraulic shearing condition, the decrease of biofilm roughness occurred during monochloramine
exposure process, while free chlorine did not change biofilm structure. This study identified the effect of
residual chlorine in DWDS on the mechanical and structural properties of biofilms, which will provide
information for biofilms control.
Brian D. Shoener
Advancing AnMBR design by identifying a pathway for sustainable technology innovation
The primary goal of wastewater treatment plants (WWTPs) is to safeguard public and environmental
health. Regulatory agencies help ensure protection of the local environment and public wellbeing through
discharge limits, but WWTPs continue to contribute to broader environmental impacts outside the purview
of NPDES permitting. A reduction in the life cycle environmental impacts of a WWTP can be achieved by
shifting away from conventional energy-intensive aerobic processes to energy-producing anaerobic
technologies (ATs). Of the current ATs, anaerobic membrane bioreactors (AnMBRs) show promise
because they reliably remove COD and provide a robust solids barrier. Given that this technology is early
in development, its successful commercialization will depend on strategic research and investment to
address critical barriers to system sustainability. In this study, quantitative sustainable design was used to
traverse a broad landscape of design and operational decisions to elucidate the economic and
environmental implications of AnMBR development pathways. By integrating cost analysis, life cycle
assessment, uncertainty and sensitivity analyses, this methodology was able to identify priorities for
10
future research and to identify sub-sets of designs that possess fundamental barriers making them
uncompetitive. Finally, a technology roadmap for AnMBR development was established to align
treatment, economic, and environmental performance along more sustainable trajectories.
Amy Benitez
Implications of Transitioning to Green Infrastructure: A Quantitative Sustainability Assessment
of Urban Storm Water Management The implementation of green infrastructure (G.I.) as a means to reduce storm water through infiltration,
evapotranspiration, and reuse is being implemented in municipalities to reduce wastewater treatment
loads (in the case of combined sewer systems) and pollution of surface water. Although G.I. technologies
are becoming increasingly common and are propounded as being universally more sustainable than grey
infrastructure, the economic and environmental implications of transitioning to green infrastructure are
unique to each municipality and project. Many sustainability assessments have been completed in the
literature comparing green and grey infrastructure, but what is lacking is a fundamental understanding of
how design and operational decisions influence the sustainability of a community as well as drainage
infrastructure. This work will elucidate sustainability implications of design decisions, including costs and
indirect impacts of green and grey infrastructure, in order to inform urban storm water management
decision making in the city of Chicago. An environmental assessment will be completed using life cycle
assessment methodology, construction and design data, remote sensing, and data from the literature.
Further, an economic analysis will quantify the cost of implementation, cost of treatment, and changes in
surrounding property values. This will be completed through the examination of public records and by
drawing from related studies in the literature. By quantifying environmental, economic, and social
impacts, a triple bottom line assessment will be completed for Chicago’s storm water management
options to help navigate tradeoffs across and within dimensions of sustainability.
Mengwei Han
Reduction of Recalcitrant Pollutants with Re Complex Catalysis and Mechanism Study
Previous work in our group has demonstrated the effectiveness of Rhenium (Re) based catalyst in
reduction of perchlorate. (citation) However, during the synthesis process, cis- and trans- isomers of the
complex appeared at equal possibility, which later displayed distinct catalytic behaviors, with trans-
isomers being the desirable product. Albeit inter-conversion between cis- and trans- isomers can be
controlled through manipulation of synthetic conditions, interests lie in diminishing the formation of cis-
11
isomers, which is achievable by adding motifs to the amino-acid based ligands. Symmetry of the Re
complex is broken due to chirality of substituted ligands, which gives rise to a series of intriguing synthetic
features, including the absolute elimination of cis-isomers in final products and the appearance of new
trans-enantiomers with different catalytic efficiency. In this presentation, we will report synthesis and
characterization of the Re complexes as well as their properties caused by modified ligands.
Homogeneous model reaction and heterogeneous engineering application of these complexes will also
be covered.
12
Poster
Richa Sehgal
Using DNDC model for estimating Nitrous Oxide and Ammonia emissions from fertilized fields in
mid-west states of Illinois, Indiana and Ohio
In this study NH3 and N2O emission flux from chemical fertilizer usage in the mid-west states of United
States is simulated. The study domain consists of three mid-west states in Unites States, i.e. Illinois,
Indiana and Ohio. These are major producers of corn, soybean and winter wheat and hence provide a
good domain to estimate the emissions of N2O and NH3.
Denitrification – Decomposition (DNDC) model, which is a process oriented agro ecosystem model is
used to estimate direct N2O and NH3 emissions from cropland in these mid- west states. The model
predicts C and N biogeochemistry in agricultural ecosystems at site scale.
The 14 monitoring stations where the simulation is evaluated are Columbus, Jackson, Muck Crops and
Northwestern in Ohio; Belleville, Champaign, Peoria, Springfield and St. Charles in Illinois; and Farmland
(DPAC), Wanatah (PPAC), Butlerville (SEPAC) and Lafayette (TPAC) in Indiana.
At each of the weather stations, a grid of size 4km x 4km for Indiana and Illinois and a grid of size 12km x
12km for Ohio is considered. These grids are predefined and data on the area of fertilized cropland
present in each grid cell in the study domain is available. ArcGIS 10.1 (ArcGIS, ESRI, CA) platform are
used to visualize and analyze spatial information. The baseline year for the model run is 2011. Grid scale
data on soil properties, daily weather, crop areas, N-fertilizer use, cropping and agricultural management
for the 14 weather stations in these 3 states are assembled.
Daily meteorological data files for all the 14 stations are prepared constituting inputs of Julian day,
maximum temperature, minimum temperature, relative humidity, solar radiation and wind speed. Fertilizer
usage files are also prepared for every weather station, with information about the different types of
fertilizers used and their quantities added at different points during a year.
Based on the input parameters of the ecological drivers, DNDC first predicts daily soil temperature,
moisture, Eh, pH and substrate concentration, and then uses the environmental parameters to drive
nitrification, denitrification, methane oxidation/ production, and other relevant geochemical or biochemical
reactions. Daily emissions of NO, N2O, CH4 and NH3 are finally calculated as their daily net fluxes.
This study will help us determine the potential nitrogen emissions in agricultural ecosystems, thus helping
13
us integrate the complex interactions among climate, soil, vegetation, soil and biogeochemical processes
in an easy and cost effective way.
Xi Chen
Multifunctional Nanostructured Composite Materials for Highly Active Reductive Catalysis Water
Purification
Multiple nanostructured metal catalysts supported by various materials are produced for reductive
catalysis. Mesoporous materials are regarded as optimal metal catalyst supports due to their highly
ordered pores with controllable sizes and large specific areas, and composite core-shell materials
combining mesoporous shells with non-porous cores (e.g., magnetite nanoparticles that facilitate
separation) are promising materials for environmental applications. In this study, we design and
synthesize a new type nanostructured composite possessing paramagnetic core coated with a
mesoporous silica outer shell containing perpendicular open channels. Nanoparticles of up to six kinds of
hydrogenation metals are loaded at the internal surface of the mesoporous channels. New synthetic
methodologies via particle surface charge tuning are developed to overcome challenges of nanoparticle
aggregation during the synthesis. The materials are characterized with scanning electron microscopy,
transmission electron microscopy, and physisorption and chemisorption analysis. Catalytic kinetics of
these composites reducing a range of aqueous contaminants (e.g., nitrate, chlorate, bromate) are
investigated to evaluate their performance in water purification. We also test the catalysis abilities of
various commercial nanostructured catalysts supported by other different materials, which first gives a
broad evaluation of their catalysis performance, and too provides a comparison for our synthesized
materials. These studies significantly expand the breadth of current nanostructured catalysts and provide
new perspectives for largescale applications.
Aimee M. Gall
Similarities between free chlorine inactivated adenovirus and bacteriophage PR772 inactivation
kinetics and viral replication cycles
With nearly a quarter of the global population consuming fecally contaminated water, waterborne
pathogens can have a significant impact on public health. Human adenovirus (HAdV), is found globally in
water sources and can cause a variety of illnesses including gastroenteritis, respiratory disease, and
conjunctivitis. HAdV is of particular concern in drinking water because of its resistance to common
14
disinfectants such as low-pressure ultraviolet light and monochloramine. The reason HAdV is so resistant
to monochloramine yet so susceptible to free chlorine remains unknown. We developed a quantitative
assay to analyze the HAdV serotype 2 (HAdV-2) replication cycle. HAdV inactivated up to 99.99% by free
chlorine still attaches to host cell monolayers, but genome synthesis as well as late hexon mRNA and
early E1A mRNA transcription are inhibited. Additionally, we have been studying bacteriophage PR772 as
a potential surrogate for HAdV-2 because of morphological and replication similarities. When exposed to
free chlorine, we have shown that PR772 has remarkably similar inactivation kinetics compared to HAdV-
2. We developed a parallel quantitative assay and observed free chlorine inactivated PR772 can still
attach to host cells and has the same inhibition of genomic replication and mRNA transcription as HAdV-
2. A more fundamental understanding of how viruses become inactivated is key for the development of
new disinfection technologies and sensors to detect infectious viruses.
Nolan Fan
Hydraulic Fracturing
Currently, the most prevalent disposal method is deep well injection, during which produced water is
pumped into porous areas between impermeable layers of rock. This solution is becoming unfavorable as
transportation costs continue to rise, regulatory agencies continue to implement more strict regulations,
and the capacity of injection wells are reaching maximum levels.
Big companies should invest in designing and implementing on-site treatment systems including
technologies such as membrane filtration and water softeners. The benefits of such an investment include
recycling of wastewater for future fracking operations, reduced waste stream, reduced fresh water
procurement costs, reduced transportation costs, and improved relations with surrounding community.
Meredith Cote
Effects of anthropogenic influences on the Maple River using a biotic index and water chemistry
analysis
Aquatic systems play an integral role in wide ranging ecological contexts by providing an outlet of nutrient
and chemical buildup. Rivers are particularly vulnerable to deleterious anthropogenic effects given their
popularity as transit and recreation waterways. The health of a stream can accurately be assessed using
an index of macroinvertebrate diversity as well as chemical concentration tests. Our study found that the
15
Maple River shows few negative effects of anthropogenic structures on macroinvertebrate health and on
overall stream health. The presence of a wetland may also have served to mitigate the effects of
manmade structures on overall stream health.
Ariel Carmichael
Bacterial Adhesion and Detachment from Model Mineralized Biofilms
Pathogen outbreak has been linked to drinking water distribution systems (DWDS), where they have
been found to be harbored in layers inaccessible to disinfectants. Biofilm growth is ubiquitous in natural
and engineered environments, including the pipe networks of DWDSs. In addition to biofilms, calcium
carbonate is also often found precipitated on pipe walls and biofilms but its role on the interaction
between the biominerals and the pathogens is still unknown. The objective of this study is to determine
the influence of calcium carbonate precipitate on pathogen adhesion to biofilms and detachment from
biofilms. Thus far, the research focus has been to create a gel with similar elastic moduli as real biofilms
to perform systematic studies of calcium carbonate precipitation within the gel and the change of gel
properties. Experiments have mainly focused on agarose, a polymer made of chains of alternating
galactose and anhydrous galactose, whose elastic modulus can be tuned by varying the agarose content
(Normand et al. 2000). Thermogravimetric Analyses (TGA), differential scanning calorimetry (DSC), and
Fourier transform infrared spectroscopy (FTIR) have been used to elucidate gel composition and
response to mineral precipitation, including the cross-linking of the polymers. The future work will focus
on the extension of these studies to real biomineralized biofilms and to measurements of adhesion
between model biofilms and colloidal particles as a function of the mineral content.
Marta Grabowski
Assessing the Environmental Impacts and Costs Associated With Construction of Roadway
Drainage Systems
Transportation systems today are moving towards sustainable design solutions in an effort to minimize
negative environmental impacts. This research focuses on the materials and construction/maintenance
phases of roadway drainage systems. By diverting water away from driving surfaces, drainage systems
are crucial to a safely functioning roadway. Roadway drainage systems typically include one or more of
the following components: Ditches, Bioswales, Culverts, Detention Basins, Pipe Underdrains, and Storm
Sewers. The selection of individual components and their detailed design is highly standardized, with little
16
or no understanding of the broader environmental and economic implications of such decisions. In
particular, broader environmental implications of drainage components can be characterized by Life Cycle
Assessment (LCA), a valuable tool that quantifies cradle-to-grave environmental impacts of an
engineered system. By coupling LCA with cost analysis, trade-offs from design decisions across
dimensions of sustainability provide a more robust assessment of roadway drainage systems.
Understanding the consequences of materials and construction alternatives will allow the transportation
industry to make well-informed design decisions and identify opportunities to advance multiple
dimensions of sustainability.
Amanda Lardizabal
Elucidation of key microalgal bioprocess design parameters on extant and intrinsic kinetic
parameters
Algal removal of nitrogen and phosphorous from wastewater is an advantageous way to prevent the
increasing problem of eutrophication and harvest algal biomass for bioenergy. Wastewater contains an
ample supply of nutrients, such as carbon, nitrogen (N), and phosphorous (P), essential to algae growth.
Therefore, as algae uptake nutrients into the cell for growth, they are concurrently achieving objectives for
wastewater treatment: N and P removal from the wastewater. Current wastewater treatment processes
using algae are not energy-positive and do not consistently remove nitrogen (including dissolved organic
nitrogen) below the current limit of technology (~ 1-3 mg-N/L). The objectives of this research are to
conduct experiments with mixed algal communities to elucidate how key bioprocess design parameters
influence extant and intrinsic kinetic parameters, as well as microalgal metabolism and the bioprocess as
a whole. These parameters will be measured in batch studies by removing biomass from a steady-state
photobioreactor (PBR) and distributing it evenly between replicate flat panel batch PBRs. Each PBR will
be exposed to the same light, pH control, air sparging, and nutrients. Samples will be taken continuously
throughout the study to monitor N and P uptake, carbohydrate and lipid storage rate and capacity, optical
density, cell concentration, and protein content. The analyzed results will then be utilized to optimize the
design of small-scale PBRs for kinetic studies with microalgae.
Lauren Valentino
Covalent organic frameworks for water purification applications
17
The increasing global demand for safe drinking water and environmental concerns about current
treatment methods have inspired research and development of novel water treatment approaches.
Membrane technologies are particularly attractive because they provide a physical barrier to water
contaminants and require no chemical additives or thermal input. Asymmetric membranes with a dense
active layer supported by a thicker, highly porous substructure offer good selectivity to remove a range of
water contaminants, high water permeability, and mechanical strength. However, in spite of its
advantages, a more widespread application of membrane technology in water treatment is limited due to
the high cost of energy and membrane operational problems associated with fouling and fouling control
strategies.
As an alternative to conventional polymeric membrane materials, covalent organic frameworks are an
emerging class of crystalline, porous organic materials, which are constructed by joining organic building
units via strong covalent bonds. Their high degree of crystallinity, in combination with the permanent and
regular pore structure, allows for the creation of one-dimensional channels that are ideal for separation
processes. The applicability and use of a covalent organic framework will be discussed.
Josue Lopez
Bio-Inspired Study on Calcium Carbonate Crystallization
Calcium Carbonate is ubiquitous in many natural systems and industrial processes. It can be found as
one of five crystalline polymorphs or as an amorphous phase, and can precipitate in both, anhydrous and
aqueous environments. While industrial processes are negatively affected by the precipitation of Calcium
Carbonate, many organisms use Calcium Carbonate as the main shell component for protection or
calcium storage. The organic molecules present in these organisms can template Calcium Carbonate and
exhibit exquisite control on the final morphology of the biomineral that forms. These complex pathways to
biomineralization are not yet fully understood. Better understanding of these mechanisms is needed for
the development of sustainable biomimetic materials.
The nucleation and surface-deposition of Calcium Carbonate is being studied with a Transmission
Interferometric Adsorption Sensor (TINaS). This technique employs a light source and a multi-layer
sensor to generate well-characterized interference patterns. Adsorbed mass on the sensor’s surface can
be detected by changes in interference patterns. A variety of organic macromolecules can be adsorbed
on the TINaS sensor to mimic templated nucleation, as observed in nature. Preliminary results show that
the formation and surface-deposition of Calcium Carbonate can be detected with this technique in real
time. Our results also show that the organic template (PEI) can favor the formation of specific crystalline
18
polymorphs.
These experimental efforts are complemented with quantum chemistry simulations. Computational
chemistry simulations can provide valuable insights of the system at the molecular scale. Preliminary
studies of Calcium Carbonate in aqueous systems have been performed to understand the behavior of
fully-solvated molecules. The first hydration shell of Calcium Carbonate has been determined rigorously
using a combination of numerous computational platforms. Our future simulations will include organic
additives to evaluate their influence on nucleation.
Hou In Cheong
Metastable calcium carbonate precipitates with organic additives
Calcium carbonate has been an interest in the study of biomineralization because of the discoveries of its
critical role in morphological control of biominerals, among others. Therefore, it becomes desired to obtain
a comprehensive understanding of the behavior and properties of organic calcium carbonate. In this work,
we are trying to elucidate the influence of organic additives in solution on the precipitation path of calcium
carbonate minerals and are especially interested on metastable phases that are stabilized by the organic
components.
Mixtures of sodium carbonate and calcium chloride solutions are done in a 1:1 stoichiometric solution at
various ionic strengths and pH-conditions, with the presence of selected amino acids, whose
concentrations will vary. The dry calcium carbonate precipitate is analyzed by Thermogravimetry,
Differential Scanning Calorimetry, and Fourier Transform Infrared Spectroscopy. The composition and
properties of the precipitates is obtained from the thermal decomposition of the organic calcium
carbonate, the heat flow produced during phase transformations of minerals, and the infrared light
adsorption as a function of wavelength. Complementary investigations are obtained by Scanning Electron
Microscopy and XRD. The analysis of these measurements will help to understand how amorphous
calcium carbonate can be stabilized by organic/inorganic interactions.
John Witter
Feasibility of of small-scale wind turbines for residential energy use in Champaign-Urbana
Analyzing the energy availability of micro wind turbines in an urban environment compared to the typical
electricity demand of an apartment of small house. Further analysis on any limitations to implementation
19
as well as environmental impacts of switching from traditional energy sources to renewable. If I have
enough time and resources I might look at the possibility of connecting to the grid, cost analysis, or ability
to store power in batteries.
Nikhil Rao Susarla
Life Cycle Analysis of Perchlorate Treatment using Bio-catalysts.
Perchlorates are extremely harmful chemicals present in eco-systems. They are both naturally occurring
and man-made used in production of various chemicals. They can also be present in some fertilizers and
bleach. They cause growth problems by disrupting hormonal functions in the thyroid. Existing methods for
perchlorate removal are hampered by the co-occurrence of Nitrate which is similar structurally and also a
more preferred electron acceptor. Enzymes present in certain microorganisms (Perchlorate Reductase
and Chlorite Dismutase) have been shown to have a high efficiency of perchlorate removal and more
importantly have a similar efficiency even in the presence of Nitrate. To ensure that this is a safe
technology to use, a Life Cycle Analysis (LCA) is conducted to assess the total impact of the entire
process from cradle to grave.
Xia Shang
Effects of poly(3,4-ethylenedioxythiophene) in asymmetric carbon electrodes for capacitive
deionization
The performance of a capacitive deionization (CDI) system consisting of conventional film electrodes is
limited by the insulating properties of predominantly used fluorinated polymeric binders. Poly(3,4-
ethylenedioxythiophene) (PEDOT) based material is known as one of the most important conductive
polymers with high electrical conductivity, pseudocpacitance, and chemical stability. In this study,
commercial PEDOT:PSS is coated on activated carbon particles and post-treated with a co-solvent
solution. The effects of PEDOT enhanced ionic and electronic mobility on salt removal and
electrochemical performance are investigated when different aqueous counter ions are used in the
electrochemical polymerization process. Moreover, the composition, morphology, and salt incorporation
mechanism are characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy,
and Fourier transform infrared spectroscopy. After characterization, asymmetric CDI systems are
assembled with selected cathode material and the salt removal rate and overall energy efficiency are
20
compared. This study provides in-depth understanding of the pseudocpacitance behavior of PEDOT in
CDI and the incorporation of different counterions in the tailored CDI electrodes.
Yijue Diao
Calcite Surface Interctions in Aqueous Solution investigated by Colloidal Probe Atomic Force
Microscopy
The formation of minerals mediated by living organisms is called biomineralization. The presence of
organic templates and organic solutes provides unique structural contributions, resulting in unique
chemical and mechanical material properties. Such a process spanning both organic and inorganic world,
requires interdisciplinary research efforts. Studies on the mechanisms of biomineralization will enable us
produce innovative materials with specific properties, which will bring about a more sustainable
environment. Among miscellaneous minerals, calcium carbonate is the most common species. The
interfacial properties of calcium carbonate in aqueous system have not been fully understood yet. In this
study, direct force measurements are conducted on a calcite substrate in water and saturated calcium
carbonate solution by Colloidal Probe Atomic Force Microscopy (AFM) in contact mode.
The classical theory for double layer interactions cannot be applied for divalent ions in aqueous solution
between dissimilar surfaces. The Poisson-Boltzmann (PB) equation is applied to describe the
electrostatic potential and to help understand surface properties of calcite. We expect to identify changes
of the surface properties of calcium carbonate during crystallization and dissolution through time-
dependent force measurements. At surface separations smaller than 5 nm a hydration force is observed
as a repulsion with superposed steps that result from the squeezing out of surface-adsorbed layers of
ions and water (as shown in Figure 1). In future work organic additives will be introduced in the system,
These studies will help elucidate the critical interaction underlying biomineralization.
The formation of minerals mediated by living organisms is called biomineralization. The presence of
organic templates and organic solutes provides unique structural contributions, resulting in unique
chemical and mechanical material properties. Such a process spanning both organic and inorganic world,
requires interdisciplinary research efforts. Studies on the mechanisms of biomineralization will enable us
produce innovative materials with specific properties, which will bring about a more sustainable
environment. Among miscellaneous minerals, calcium carbonate is the most common species. The
interfacial properties of calcium carbonate in aqueous system have not been fully understood yet. In this
study, direct force measurements are conducted on a calcite substrate in water and saturated calcium
carbonate solution by Colloidal Probe Atomic Force Microscopy (AFM) in contact mode.
The classical theory for double layer interactions cannot be applied for divalent ions in aqueous solution
21
between dissimilar surfaces. The Poisson-Boltzmann (PB) equation is applied to describe the
electrostatic potential and to help understand surface properties of calcite. We expect to identify changes
of the surface properties of calcium carbonate during crystallization and dissolution through time-
dependent force measurements. At surface separations smaller than 5 nm a hydration force is observed
as a repulsion with superposed steps that result from the squeezing out of surface-adsorbed layers of
ions and water. In future work organic additives will be introduced in the system, These studies will help
elucidate the critical interaction underlying biomineralization.
Alexis Sheehan
Effects of Nanoscale Roughness on Ionic Liquid Surface Behavior - Smart Interfaces for
Environmental Nanotechnology
As the demand for renewable energy increases, so does the need for safe and efficient large-scale
energy storage and delivery systems that can function under varying loads and a wide array of
temperatures. Supercapacitors, also known as EDLCs (electrical double layer capacitors), have this
flexibility while providing higher energy storage than traditional capacitors and greater power output than
batteries. My research aims to increase the viability of supercapacitors for storage and distribution of
renewable energy through the use of ionic liquids an electrolyte replacement.
Ionic liquids exhibit high charge densities, low volatilities, low flammability and large electrochemical
windows while remaining largely chemical inert, which make them good candidates for electrolyte
replacements. However, many of the processes that dictate the formation of electrical double layers, as
well as fundamental interactions with the electrode surface are mostly unknown. This hinders the ability to
design efficient electrochemical cells using ionic liquids. Much of the research being completed focuses
on ionic liquid interactions with smooth surface such as graphene. However, a true electrochemical cell
uses rough carbon-based surfaces.
I will focus on modifying a smooth surface, silicon, into a surface with a well-defined roughness. This is
completed using poly(ethyleneimine), PEI, to charge the surface of the silicon. Then adsorbing silica
nanoparticles onto the PEI. Finally the silica nanoparticles are sintered to silicon wafers. This will create a
surface with a known nanoscale roughness.
In the coming months, ionic liquids will be placed in droplets on smooth and rough silica. Using atomic
force microscope (AFM) force curves and friction measurements will be taken. These AFM
measurements will be used to characterize changes in surface-ionic liquid interactions, thickness and
22
composition of the double layer caused by the well-defined roughness. Future work will consist of laying
graphene over the roughed silicon to create graphene with a known roughness and completing force
curves and friction measurements to better understand the effect of roughness on ionic liquid functionality
in electrochemical cells.
Laura Southworth
Understanding organic fouling in membrane capacitive deionization systems to enhance water
reclamation sustainability
Membrane capacitive deionization (MCDI) systems have the potential to lower the energetic demand of
freshwater production from unconventional sources like brackish water and reclaimed wastewater through
direct treatment or by treating brine generated by existing pressure-driven systems like reverse osmosis
(RO). Organic fouling at filtration interfaces significantly increases energy consumption and adversely
impacts freshwater production rates by obstructing water flux through the membrane. While RO fouling
has been well characterized, little is known about the impact of organic foulants on ion adsorption in
MCDI systems. In these systems, fouling layers could accumulate on the ion exchange membrane or the
electrode itself, impeding flux and adsorption of ions out of bulk solution and onto the charged electrodes.
Electrode potential could also impact foulant accumulation, producing fouling mechanisms distinct from
those of RO fouling. Synthetic saline solutions containing model organic foulants will be used to evaluate
MCDI fouling potential. Feed solutions will run through a lab-scale MCDI system, and the extent of fouling
and scaling will be evaluated by observed changes in desalination performance and flow path pressure
drops. Scanning electron microscopy and energy-dispersive X-ray spectroscopy will be used to
characterize the electrode structure before and after fouling to evaluate the extent of structural changes.
Atomic force microscopy (AFM) will be used to measure the interaction forces between a charged
colloidal AFM tip and polarized electrodes under different set potentials and solution conditions. Several
cleaning solutions will be tested on the fouled membranes, and the extent of recovery of initial
desalination performance, flow path pressure drops and structure will be measured.
Yew Chin Raymond, Choo
Surface force apparatus in environmental science
Many processes in environmental engineering are driven by surface phenomena as they involve bodies
of micro scale dimensions. For example, in water treatment, surface interactions are responsible for initial
23
flocculation and coagulation of small colloids to form larger particles that can be effectively removed by
sedimentation. Activated carbon, used for the adsorption of contaminants, is widely adopted because of
its large surface area to mass ratio. The fouling of membranes, a pertinent problem with membrane
filtration, is largely attributed to undesirable surface properties that favour foulant attachment. The study
of surface science enables a better understanding of the fundamental mechanisms behind these
processes.
The surface force apparatus (SFA) is an instrument that directly measures surface forces. Over the past
50 years, SFA measurements have provided insights into the nature of electrostatic surface, Lifshitz/van
der Waals and solvation/hydration forces. The power of the SFA comes from its ability to measure forces
at sub molecular separation distances. This precise determination of separation distance is achieved
utilizing white light interferometry while force measurement is determined by a spring connected to a
cantilever. In contrast to the atomic force microscopy (AFM) technique, the absolute separation distance
measured from interferometry is used to calculate the force magnitude in the SFA. This precise
determination of separation distance is one of its advantages. Another advantage is lower stresses due to
a larger contact area.
The Smart Interfaces in Environmental Nanotechnology group is home to the eSFA-II. The instrument
features automated real time spectrum correlation for separation distance measurement. Housed in a
thermally insulated box and anti-vibration table, the combined thermal and mechanical drift is as low as
20pm/min with resolution of 15pm. Upcoming experiments with the instrument aim to investigate
molecular ordering of ionic fluids in confinement and interaction between graphene surfaces intercalated
by a fluid layer.
Yuting Chen
Thermal Stability Study of Ionic Liquids
21st Annual UIUC EES Spring SymposiumThermal Stability Study of Ionic Liquids
Yuting Chen, Andres Jurado, Rosa M. Espinosa-Marzal,
Civil and Environmental Engineering, University of Illinois at Urbana-Champaign
Abstract
Room temperature ionic liquids are organic moleten salts that are liquid below 100 °C. Nowadays, Ionic
liquids (ILs) are receiving more and more attention due to many practical applications, especially in the
field of renewable energy as electrolytes for supercapacitors, solar cells, fuel cells, or heat transfer fluid.
In order to better understand the performance of ILs in various conditions, the thermal stability of the ILs
24
must be evaluated. The Differential Scanning Calorimetry (DSC) is used to determine the temperature at
which phase change (crystallization/ glass transition/ melting) happens and the involved heat of
transformation. In this work, the thermal stability of Emim-EtSO4 (EE), Hmim-EtSO4 (HE), and Hmim-Ntf2
(HN) were studied. The temperature was ranged between -75ºC to 100 ºC, with a scanning rate of 10 ºC
and 2 ºC per minute, respectively. The results for EE were in agreement with previously reported results.
The HN data showed a pronounced melting peak at a temperature of -7 ºC and a crystallization peak at -
33 ºC, which were also consistent with published data. Moreover, a small melting peak was observed at -
0.9 ºC, which is likely by the melting of residual water (~0.2 wt%) in HN, suggesting the presence of water
clusters in HN. On the other hand, the HE samples were tested after storage in the DSC pans for different
periods of time. For HE a broad melting peak was observed after 18 days, which indicates the change of
the nanostructure (freezing) with time. The results also suggested that moisture may play a significant
role on the thermal properties of the ILs. Therefore, we will investigate the influence of water content on
the thermal stability of the ILs in a systematic way in our next experiments.
Zhuojun Yu
China’s climate-change policy to address Climate Change
In order to address the global environmental issue, China has signed Kyoto Protocol on May 29th, 1998,
and ratified it on September 3rd, 2002, and formed the Asia-Pacific Partnership (APP) on Clean
Development and Climate with Australia, India, Japan, Korea and the United States. In demotic policy, for
drawing up a plan under the Kyoto Protocol after 2012, the State Council of China officially issued its
"Twelfth five-year" control scheme for greenhouse gas emissions in December 2011. This scheme made
an overall arrangement for controlling the greenhouse gases emissions and clearly defined the
greenhouse gases emission target from 2011 to 2015.
Xiangchen Huo
Catalytic reduction of nitrate and nitrite in solution by Ru catalysts
The performance of supported Ru catalysts on catalyzing nitrate and nitrite reduction by hydrogen was
investigated. Ru showed high activity of nitrate reduction but low activity of nitrite reduction. When Ru was
employed alone, ammonium dominated the product of nitrate reduction, and was not influenced by initial
nitrate concentration. In contrast, selectivity of ammonium during nitrite reduction decreased with
increasing initial concentration of nitrite. Neither physical mix of Pd with Ru nor deposition of Pd on
25
carbon supported Ru affected nitrate reduction activity or product selectivity, raising the question whether
nitrite is an intermediate from nitrate reduction. Ru is a potential alternative for catalytic nitrate reduction
in terms of competitive cost, high activity, and applicability in a wide range of solution pH. But effort is
needed to improve its product selectivity.
Hanting Wang
Quantification of rotavirus removal in biosand filters using an integrated cell culture and reverse
transcription quantitative PCR assay
Diarrheal diseases caused by pathogens remain a constant threat to millions of people around the world
who lack access to safe or improved drinking water sources. Recent studies on biosand filters, a
commonly used point-of-use technology for treating drinking water, have shown that bacteria and
bacteriophage removal can reach USEPA and WHO standards. However, the efficiency of human enteric
virus removal in biosand filters has not been studied. Rotavirus was used in this study because it is the
leading cause of diarrhea in children under the age of 5 around the world. Two scaled down PVC biosand
filters with 55 cm sand depths were used to determine the efficacy of rotavirus removal as a function of
depth, residence time, and flow rate. One filter was fully ripened and the other was unripened at the start
of the experiments to compare rotavirus removal at different media aging periods. An integrated cell
culture and RT-qPCR assay was developed to quantify rotavirus removal in water samples collected from
the filters. Preliminary results show that the assay is more sensitive and has a lower detection limit (10^-2
FFU/mL) compared to the standard rotavirus infectivity test (10^2 FFU/mL) or RT-qPCR (10^1 FFU/mL)
alone. This is the first study to determine the efficiency of rotavirus removal in biosand filters, which is an
essential first step in understanding the extent to which biosand filters can remove human enteric viruses,
and hence reduce diarrheal disease incidences.
Heather Gipp
Phytoremediation of Lead using Urban Trees
Lead pollution is very prevalent in urban areas due to industrial processes and commercial products. In
an urban environment, using arborous species for phytoremediation would be a sustainable option for
long-term remediation. However, arborous species are typically less efficient in accumulation. With
application techniques such as EDTA and biochar soil amendments, there is a possibility that lead
accumulation by trees could be enhanced. This project, which took place at the Morton Arboretum in
26
2013, studied the lead phytoremediation capabilities of Salix alba and Platanus x acerifolia, two common
urban trees that have shown phytoremediation capabilities. The experiment was conducted in a
greenhouse setting with soil microcosms and studied the effects of EDTA and biochar additions on lead
accumulation by urban trees. After harvesting the trees and collecting the soil, plant biomass and soil
samples were digested and lead levels were analyzed on the atomic absorption spectrometer. Results
showed that the Salix alba had a much higher biomass than Platanus x acerifolia. However, the Platanus
x acerifolia had a much higher mg Pb in biomass/kg Pb in soil, so the uptake of lead by Platanus x
acerifolia could have inhibited its growth. Biochar application did not show a strong increase in lead
accumulation. The effect of EDTA on the plants showed an increase in lead uptake, but a decrease in
plant growth.
Abiodun Oki
Novel tailor-made dendrimer based nanofiltration membranes
In this work, we describe how novel membranes which are at the boundary of ultrafiltration and
nanofiltration can be developed using novel tailor-made dendrimer based materials that can be tuned and
functionalized as the active layer of the membrane. We achieve this via an interplay of organic synthesis,
material characterization and physics of separation to develop membranes that can reject both small
colloidal and dissolved organic matter while at the same time selectively allow the passage of inorganic
ions, yet possess resistance to fouling and chemical degradation. In this way, we intend to make progress
in fundamentally understanding the mechanisms involved in the surface and transport interactions of
water, dissolved organic matter and ions during membrane separation, hence enabling further advances
in the development of new membrane materials in the future.
Andrew J. Nelson
Measurement of Ammonia Exchange above a Fertilized Maize Canopy
Use of nitrogenous fertilizers for agricultural crop production contributes more than 50% of total
anthropogenic ammonia (NH3) emissions in Illinois. NH3 emission results in the formation of small
diameter (≤2.5µm) particulate matter; (PM2.5), that have adverse effects on health and visibility and can
modify the radiative balance of the Earth . The emission of gaseous NH3 from agricultural cropland is not
well characterized, having been experimentally quantified for a limited number of crop types and
locations. This research seeks to improve the understanding of NH3 emission above a maize canopy in
central Illinois.
27
A relaxed eddy accumulation (REA) system was designed, deployed, and operated above a fertilized
maize canopy at the University of Illinois at Urbana-Champaign (UIUC) Energy Biosciences Institute (EBI)
Energy Farm in Urbana, IL during the 2014 growing season. Average NH3 flux and concentration was
measured throughout the growing season, focusing particularly on the first four weeks after fertilization.
Maximum NH3 concentration (8.11 µg/m3) was observed during the period nearest fertilization. Similarly,
maximum positive NH3 flux (transport away from the surface) was observed in the three-week period
following fertilization (430.2 ±347.0 ng/m2/s) with lower positive flux observed for the remainder of the
season (31.7 ±104.5 ng/m2/s).
Kan Fu
A case study of Weather Research and Forecasting model over Midwest USA
Air pollutants, such as particulate matter and ozone, continue to cause environmental problems and
threaten humans’ health, and it is essential to understand how they are formed, transported and removed
from the atmosphere before control strategies are implemented. Chemical Transport Models (CTMs) can
be useful tools to estimate concentrations of these pollutants given emission intensities of primary
pollutants and meteorological conditions, thus supporting policy making. A good prediction of CTMs relies
heavily on accurate meteorological data as inputs. The Weather Research and Forecasting (WRF) model
is a numerical weather prediction model that is commonly used to provide input to CTMs. The WRF
model includes a number of domain configurations and parameterizations to accommodate various
spatial resolutions and regional characteristics. Therefore, before the WRF output is used as input to a
CTM, the most appropriate parameterization needs to be identified.
WRF simulations were conducted over Midwest USA for May 2011. The WRF output will be used to
process gridded emissions and as input to a CTM with the intention to study effects of reactive nitrogen
emissions to the atmosphere from intensive fertilizer usage on air pollutant formation, transport and
deposition. Meteorological station measurements of wind speed, wind direction, temperature, precipitation
and relative humidity were used to evaluate the WRF output. The WRF output was optimized by
considering the nesting method, input dataset choice, and grid spacing. Sensitivity analysis was done to
optimize the combination of WRF physics options in microphysics, land surface model, planetary
boundary layer, radiation and cumulus cloud parameterizations.
Michael Cunningham
28
Impact to Water Quality from Hydraulic Fracturing
Gas well drilling has grown exponentially since 2008 after advances in drilling technologies allowed the
capture of natural gas and oil reserves from shale and tight sand formations. Hydraulic fracturing uses
large volumes of high-pressured water and a mixture of toxic organic and inorganic chemicals to obtain
these reserves. My goal will be to explore the pathways for drinking water contamination from fracking
sites, and research the water treatment options available to decrease the risk of exposure to the
surrounding environment.
Yichen He
Modeling Interactions between Cells and the Aqueous Environment
Nanoparticles, heavy metals and ions generated from industry that are released to the aqueous
environment, may react with microorganisms and be toxic to them. The main goal of this research is to
investigate the interactions between model cells and the aqueous environment. In this work, the model
cell membrane consists of a polymer-supported lipid-bilayer, specifically, a polyacrylamide hydrogel, and
supported Eggphosphatidycholine (EggPC). Hydrogels are cross-linked polymer networks that can
absorb large amounts of water, and are very compliant. Both, (neutral) polyacrylamide, and (negatively
charged) acrylamide-co-itaconic acid hydrogels were characterized in swelling/collapsing experiments;
the adsorption kinetics of bovine serum albumin (BSA) and ε-polylysine under controlled conditions of pH
and ionic strength was determined by a Transmission Interferometry Adsorption Sensor. The results show
that the adsorption of both BSA and ε-PLL by charged hydrogels is much stronger than by neutral
hydrogels. Furthermore, strong absorption into the gel pores is observed in both of them. These
measurements suggest that both, i) electrostatic interactions , and ii) the different network structure
provided by the itaconic acid, may influence adsorption and absorption. Accurate interpretation of these
data requires precise knowledge of the hydrogel mechanical properties. Thus, nanoindentation of both
neutral and charged hydrogels using atomic force microscopy (AFM) is used to study the mechanical
behavior. A spherical indenter with 5-µm radius was used in the experiments and all indentations were
done with the hydrogel completely immersed in water. Polyacrylamide gels were tested under different
loading rates and the Herz equation was used to model the results. The results show an increase of
hydrogel Young’s Modulus with loading rate, which is characteristic of viscoelastic response. In the last
part of this work, the influence of the lipid bilayer on both, adsorption and mechanical properties will be
investigated. The long-term goal of this project is to establish an experimental platform that can be used
to investigate cytotoxicity.
29
Laura Fierce
Quantifying the impact of particle composition on light absorption by black carbon
absorption. For example, if particles in BC populations were assumed to have uniform composition,
similar to the representation applied in modal models, absorption enhancement was overestimated by as
much as a factor of two relative to more realistic treatments of particle composition. By applying realistic
distributions of particle composition from a particle-resolved aerosol model, we found weak absorption
enhancement at low relative humidity (Eabs = 1±1.3), consistent with ambient observations that are
performed at low relative humidity. On the other hand, we found strong absorption enhancement (Eabs >
1.8) in many locations if particles were modeled using the global variation in relative humidity.
Bernardo Vazquez Bravo
Inactivation of Adenovirus with Filtered Polychromatic Medium-Pressure Ultraviolet Light
Ultraviolet (UV) light is a drinking water treatment technology that has been gaining popularity due to
increased concern about disinfection by-product formation when chlorine is used as disinfectant. UV light
does not produce by-products at the doses commonly used in the water treatment industry. There are
different sources of UV light that are commercially available but the most commonly used are
monochromatic low-pressure (LP) and polychromatic medium-pressure (MP) UV lamps. Human
adenovirus, a double stranded DNA virus, has been recognized as the waterborne pathogen with the
highest resistance to UV light inactivation. In this study the inactivation of adenovirus 2 was assessed by
plaque assay and combined with molecular techniques such as RTqPCR, and Long-Range (LR)PCR to
elucidate at which step of the viral infection cycle adenovirus is getting inhibited. Specific wavelengths
within the germicidal range (200-300 nm) were isolated from a MP lamp source using band-pass filters
and evaluated to assess different steps of the virus infection and target components of the virion. The
findings of this work will help to better understand the mechanism by which UV light inactivates viral
pathogens and which component of the virus is being damaged during disinfection.
Andrea Vozar
Characterization of protein adsorption on polyamide water filtration membranes
Nanofiltration (NF) and reverse osmosis (RO) membranes are barrier-based water treatment technologies
able to provide rejection of all pathogens and most organics, emerging contaminants, and multivalent
30
ions. RO membranes also reject monovalent salts. Polyamide is a state-of-the-art NF and RO active
layer material and is highly susceptible to fouling, or the build up of unwanted organic compounds on a
membrane surface. 30% of the energy consumption in current polyamide membrane applications is
attributed to fouling. Polyamide is not used presently with high organic content waters, such as
wastewater or during seawater algal blooms.
There are three forces acting at the membrane-feed solution interface: adsorptive molecular forces,
pressure, and shear. The adsorption of a surrogate protein onto four commercial NF and RO membranes
with different pores size, active layer thickness, roughness, and surface coatings are compared. Batch
adsorption experiments are performed to determine the effect of pH on (1) protein adsorption and (2)
protein adsorption when divalent cations are present. Membrane active layer and fouling layer surface
properties are measured using microscopy techniques. Distinguishing between the polyamide and the
protein is challenging as both are composed of the same elements: hydrogen, carbon, oxygen and
nitrogen. The protein is modified with a known quantity of halogen to differentiate them. Rutherford
backscattering spectrometry (RBS) shows protein adsorption decreases to zero with increasing pH.
Membranes with more terminal amine groups have higher protein adsorption, indicating the protein
adsorbs to polyamide protonated amines. In the presence of a divalent ion, protein adsorption varies
similarly to the protein only adsorption below the pKa of the membrane carboxylic group. Above the
membrane carboxylic group pKa, protein adsorption is higher and never zero when divalent ions are
present. It is hypothesized because of the presence of the protein at high pH that divalent ion bridging
occurs between the deprotonated carboxylic acid on the membrane surface and a negatively charged
group on the protein.
Erin Bak
Antibacterial Calcium Carbonate
The objective of this project is to synthesize biodegradable micro- and nanoparticles based on calcium
carbonate to be used for water treatment purposes. Polycationic natural and synthetic polymers have
been shown to interact electrostatically with bacteria and kill them. Thus, single calcite crystals and the
mineral particles are coated with selected polyelectrolytes. The adsorbed mass of polyelectrolytes on the
mineral is measured with a Quartz Crystal Microbalance and interferometry. Atomic Force Microscopy
(AFM) is used to measure the interaction forces between the coated mineral particles as well as the long-
term resistance of the polymers grafted to the mineral. Our measurements indicate that the polymers
stabilize the particles in solution.
31
The outlook of this project is to prove the antibacterial action of the coated mineral particles and the rate
of dissolution under various environmental conditions. For this purpose we plan to combine AFM with
fluorescence microscopy, among other techniques. Escherichia coli (E. coli), a rod-shaped member of the
coliform group, has been chosen for these future studies.
Sital Uprety
Effects of climate-induced changes in water quality and risk of diarrheal diseases in Nepal and
Uganda
Poor water quality and limited sanitation is resulting in estimated 3.5 billion diarrheal episodes and
causing 1.87 million childhood deaths per year world from diarrhea, mostly in developing world. Climate
change is likely to have wide range of health effects on these communities in that lack adequate water
and sanitation infrastructure. The study proposes that drastic change in hydroclimatic process such as
extreme drought and precipitation in Uganda and Nepal leads to differences in microbiomes of water due
to changes in gut microbiomes of individuals and subsequent outbreaks of pathogens. The study will
monitor several cycles of drought and wet seasons in Nepal and Uganda and will be investigated for
abundance and distribution of diarrhea-causing pathogens and other microbes using metagenomics. The
results of metagenomics will guide microfluidic quantitative PCR which will allow comprehensive and
simultaneous determination of all diarrhea causing pathogens. This information can be used to modify the
existing drinking water system to consider climate change as a factor and also can be used to create a
model to predict the outbreak of diarrheal diseases in the future.
Ian Bradley
Selection of lipid and carbohydrate accumulators for enhanced algal feedstock production and
nutrient recovery from wastewater
Algae are one of the most promising bioenergy feedstocks of the 21st century. Productivity of converting
CO2 to carbon rich lipids for biodiesel is nearly 10x greater than the most efficient traditional crop, oil
palm, and over 130x and 340x more productive than soybean and corn, respectively. However,
production of biofuels from algae is still prohibitively expensive. Coupling algae production with
wastewater treatment can offset the high energy and nutrient demands that make algal biofuels so costly.
Currently, there is a fundamental lack of understanding concerning the impact that real-world
environmental factors (e.g. light intensity, operating parameters, competition between organisms) have on
32
algae growth in wastewater and production of carbon storage compounds such as lipids and
carbohydrates. Understanding and predicting the rate at which these storage compounds are produced
and degraded is critical to the design of efficient processes for algal growth. Preliminary work using pure
culture Chlamydomonas reinhardtii has been performed to better understand the effects that nitrogen and
phosphorous starvation have on increasing organic carbon storage. Additionally, mixed community
growth on high strength wastewater has been demonstrated. This presentation will discuss the results,
along with methods and proposed work aimed at selecting for specific carbon storage compounds within
mixed wastewater communities for improved algal feedstocks.
Andrea Vozar
Characterization of protein adsorption on polyamide water filtration membranes
Nanofiltration (NF) and reverse osmosis (RO) membranes are barrier-based water treatment technologies
able to provide rejection of all pathogens and most organics, emerging contaminants, and multivalent
ions. RO membranes also reject monovalent salts. Polyamide is a state-of-the-art NF and RO active
layer material and is highly susceptible to fouling, or the build up of unwanted organic compounds on a
membrane surface. 30% of the energy consumption in current polyamide membrane applications is
attributed to fouling. Polyamide is not used presently with high organic content waters, such as
wastewater or during seawater algal blooms.
There are three forces acting at the membrane-feed solution interface: adsorptive molecular forces,
pressure, and shear. The adsorption of a surrogate protein onto four commercial NF and RO membranes
with different pores size, active layer thickness, roughness, and surface coatings are compared. Batch
adsorption experiments are performed to determine the effect of pH on (1) protein adsorption and (2)
protein adsorption when divalent cations are present. Membrane active layer and fouling layer surface
properties are measured using microscopy techniques. Distinguishing between the polyamide and the
protein is challenging as both are composed of the same elements: hydrogen, carbon, oxygen and
nitrogen. The protein is modified with a known quantity of halogen to differentiate them. Rutherford
backscattering spectrometry (RBS) shows protein adsorption decreases to zero with increasing pH.
Membranes with more terminal amine groups have higher protein adsorption, indicating the protein
adsorbs to polyamide protonated amines. In the presence of a divalent ion, protein adsorption varies
similarly to the protein only adsorption below the pKa of the membrane carboxylic group. Above the
membrane carboxylic group pKa, protein adsorption is higher and never zero when divalent ions are
present. It is hypothesized because of the presence of the protein at high pH that divalent ion bridging
33
occurs between the deprotonated carboxylic acid on the membrane surface and a negatively charged
group on the protein.
Anna Fedders
Evaluation of infrared spectroscopy as a tool for biomass characterization in microalgae
Algae are increasingly being investigated for use as feedstock for biofuel production, hydrothermal liquefaction, and other industrial processes. For each of these potential applications, rapid and accurate characterization of algal biomass as carbohydrate, lipid, and protein fractions is essential. Traditional wet chemistry methods typically require large amounts of biomass, are time consuming, and frequently involve the use of hazardous chemicals. Recently, novel spectroscopic methods have been proposed which use near-infrared (NIR) or fourier transform infrared (FTIR) spectroscopy to quantify algal biomass composition. While numerous methods have been published on the subject, more work is needed to determine how data can be best standardized and analyzed to maximize method precision and accuracy in both pure- and mixed-culture systems. Suggestions for addressing these knowledge gaps will be proposed.
Daniel Mosiman
Comparison of Fluoride Removal Capacities by Different Low-Cost Materials
Fluoride is a common constituent of natural waters due to the abundance of fluorine in the Earth’s crust.
Consequently, toxic fluoride exposure is endemic, chiefly in East Africa, India, and China. The World
Health Organization (WHO) estimates that at least 200 million people are at risk for acquiring dental
fluorosis, resulting in the browning of teeth, and that more than 10 million are at risk for acquiring skeletal
fluorosis, causing bone deformation, joint pain, and crippling. Most of these people cannot afford the high-
tech defluoridation solutions or manage their high maintenance, driving research for low-cost, simple,
effective, and socially acceptable treatment options. Due to these constraints, researchers favor
adsorption processes, and bone char (BC), a naturally derived hydroxyapatite (HAP, chemical formula:
Ca5(PO4)3OH), is well suited. However, like many fluoride adsorbents, BC’s fluoride adsorption capacity
is dismally low (~3-5 mg-F/g-BC); in addition, BC cannot be easily manipulated in a way that could
34
enhance its fluoride adsorption capacity, such as increasing its surface area or modifying its crystalline
structure. Furthermore, the mechanisms by which fluoride is adsorbed by HAP are not understood well,
which limits the potential to modify HAP in a. This research focuses on fluoride removal by HAP pellets
that mimic BC. Due to its production process, which essentially comprises of precipitation and
compaction, these pellets can be manipulated rather easily. During compaction, sawdust (d < 0.6 mm)
was incorporated into the HAP. The dried pellets were then sintered at 500°C to remove the sawdust and
thereby create a higher surface area. Fixed-bed columns were used to compare fluoride adsorption
capacities of BC, HAP, and the manipulated HAP. In addition, effluent concentrations of relevant
parameters were monitored and analyzed to help elucidate fluoride removal mechanisms.
Olabimpe Akinbobola
Resilience to Climate Change in Developing Countries
Climate change is when there is a variation in an average weather of a region. This variation leads to the
occurrence of extreme and severe weather conditions that exacerbate the environmental conditions (air
and water quality, food security) of the affected region.
The effect of global warming caused by greenhouse gases and other natural sources are known to be the
paramount source of climate change. Consequently, climate change causes droughts, rise in
temperature, flood, rise in sea level, intense rain, fire, extreme storms, snow melts, ecological effects, and
many other direct/indirect impacts. These impacts are sustainable if the society could develop resilience
through adaptation, and other adaptive management methods that could help minimize vulnerability.
Resilience can be measured as a way a community reverted to an equilibrium state after a disturbance,
or when a community resists change and persistency to recover after perturbation (Brock, 2003).
The developing countries have so many factors working against them, most predominantly, lack of
financial support, water and food insecurity, poor infrastructure and technologies. All these factors
exacerbate their vulnerability.
Megan O'Donnell
Use of Low Impact Development (LID) Strategies to Manage Stormwater Runoff
Stormwater runoff increases with impervious land cover and can be an issue for urban areas where a
substantial portion of surfaces are impervious. Stormwater runoff impacts water quality by transporting
sediments and pollutants it comes into contact with as stormwater sheet flows to drainage features.
35
Impacts of stormwater are exacerbated in urban areas that utilize a combined sewer system (i.e.
wastewater and stormwater are combined and transported to a treatment facility in the same sewer
system) due to combined sewer overflow (CSO) during large storm events. Some cities have begun
implementing low impact development (LID) strategies when updating and renovating stormwater
infrastructure in order to reduce the aforementioned impacts. LID designs may include permeable
pavements, bioretention features, and rain capturing devices. This project will examine the need for LID
strategies and explore case studies in which such strategies have been implemented.
Ran Mei
Microbial community response of a mesophilic methanogenic enrichment to temperature
perturbations
Anaerobic digestion (AD) provides an environment for microorganisms with different metabolic functions
to cooperate and metabolize complex organic compounds to methane and CO2. Previous studies have
reported that temperature control was essential in AD operation, and temperature fluctuation could lead to
process instability and in some cases process failure. Nevertheless, the understanding on how AD
microbiota respond to temperature shocks is rather poor. It remains unclear which group(s) of microbes
are vulnerable to heat shock and which are responsible for the recovery of substrate degradation after
heat shock. To systematically address these questions, a mesophilic benzoate-degrading methanogenic
enrichment was exposed to different levels of temperature perturbation from 45°C to 70°C for 5 or 15 min.
Comparing to control treatment, we observed three types of methane production profile: not inhibited at
45 and 50°C, inhibited first and recovered later at 55 and 60 °C, inhibited and not recovered at 70°C.
These responses could be further explained by the microbial community analysis based on 16S rRNA-
and rRNA gene-targeting sequencing. A Syntrophus-related population, the major benzoate-degrading
syntroph, was highly correlated to heat shock temperature, and its abundance was crucial to the
restoration of benzoate degradation after the perturbation. In contrast, the abundance of methane
producers was relatively stable regardless whether methane production was inhibited. Different response
patterns were observed with other bacterial species, and could be used to understand their potential
physiological traits and ecological niches in the AD microbiota. For example, significant increase in
abundance was observed with a Firmicutes-related population (>50% in total population), which is likely a
spore-forming biomass degrader. Growth was stimulated for members of WWE1, Spirochaetes,
Bacteroidetes and Thermotagae, and inhibited with another member of Spirochaetes. While the exact
roles of these minor microbial populations are unknown, they are ubiquitous and functionally important in
AD. Overall, temperature perturbation provided an effective way to shed insights into the microbial
36
populations in AD, and can further generate knowledge on how to deal with unexpected heat shock, a
common accident, thus improve the stability and performance of AD processes.
Fabian
Development of a genetic algorithm model for green infrastructure optimization design to reduce
nutrient pollutant load in the receiving stream
Green infrastructure has been widely studied and reported as part of Low Impact Development (LID)
approaches to replace or complement existing storm water strategies.
Research on green infrastructure focused on water quality is often limited to laboratory work testing
different materials, substrates or configurations. However, the modeling of the water quality resulting from
a green infrastructure network has not been widely explored at the watershed scale.
Nutrients are particularly interesting due to some evidence and consistent results that show Green
Infrastructure, such as rain gardens or green roofs, actually can be a source instead of a sink of nitrates
and phosphates. In riparian watersheds the nutrient export to a receiving stream could lead to
eutrophication conditions and affect equilibrium of the ecosystem.
Different studies have been conducted in order to optimize the benefits of green infrastructure such as
peak flow reduction and total volume of storm water. Following the same approach, the total load of
nutrients exported to the outlet of an urban network can also be optimized. Genetic algorithms are
adaptive methods that can be used for single- and multi-objective optimization; they are based in the
principles of genetic evolution and natural selection. Similar to natural behavior, a genetic algorithm has a
population of individuals (chromosomes), and each one is a feasible solution to a given problem. Each
“individual” is evaluated with a model of the green infrastructure network to evaluate its fitness
(performance relative to the design criteria). The best solutions are selected to form new solutions
(offspring) in a process that will repeat until the algorithm converges to the best designs. Genetic
algorithm are widely used in optimization problems where the objective function is discontinuous,
nonlinear, stochastic, or where the data are not reliable.
The research I will discuss is focused on the development of the genetic algorithm optimization model in
order to achieve the best green infrastructure configuration and design, finding what spatial and temporal
scale works better for an urban watershed model.
Kevin Hade
37
Comparing long-term and short-term emission impacts from infrastructure using a simple model
Existing infrastructure such as building shells or roads have long lifetimes, and thus the emissions they
cause can persist well into the future. Although present-day emissions from these sources are quantified,
long-lived infrastructure can also influence future development and transportation choices and shape
emission trajectories and climate as a result. To understand the impacts of infrastructure on expected
future emissions, it is important to quantify how emissions respond to long-lived infrastructure taking into
account the carbon commitment or lock-in resulting from the infrastructure’s long lifetime and the resulting
response of Earth’s temperature. In this study a simple model was used to estimate the Earth’s
temperature response to a time-dependent emission function. Outputs from this model are used to
compare the short-term and long-term climate forcing that result from emissions from infrastructure over
time.
Qing Wei
Evaluation of the Effectiveness of the Forest Program of the Convention on Biological Diversity
Forests play a crucial role in the economy and social development of many countries. More than 1.6
billion people depend to varying degrees on forests for their livelihoods. Unfortunately, forests continue to
be lost and degraded at a high rate. The goals of this research were to identify challenges in
implementing the forest biodiversity protection programs in developing countries and provide
recommendations for improving its effectiveness. The implementation of the CBD has been generally
difficult because there are major problems in biodiversity conservation and equal sharing of benefits
arising from biodiversity in developing countries. The first significant challenge in Bangladesh is to clearly
define the terms “forest,” “deforestation,” “reforestation,” and “afforestation” where misunderstanding and
misinterpretation are likely to arise. Second, the planned protected areas in Bangladesh remain
unprotected due to the increasing deforestation rate and population. Third, the government of Bangladesh
failed to manage the national land uses. Although 193 countries ratified the CBD, a number of parties
have difficulties in implementing it. The author gave recommendations for improving the effectiveness of
the CBD. First, in order to promote gain credits, developed countries can support technical and financial
supports to developing countries, assisting developing countries in the development of conserving forest
and compensating developing countries for the preservation of tropical areas. Second, effective law
enforcement is required as a basic foundation of any conservation strategy, especially important for the
implementation of the CBD, requiring protection and/or the restoration of “legal forest reserves” and
“areas of permanent protection” on all proprieties. Third, integrate the diverse regulations and public
policies, new opportunities and incentive mechanisms for forest protection and restoration, and various
38
independent projects and programs carried out by governments and NGOs into a single and
comprehensive strategy for establishing networks of sustainable landscapes.
Diana Kapanzhi
Life Cycle Assessment of a Multifunctional Woody Polyculture: advancing goals for sustainable
food production through perennial agriculture.
The goal of the iSEE funded project is to establish UIUC as a global leader in perennial polyculture
research. A woody polyculture cropping system has several advantages over conventional annual
cropping, including storage of carbon, vertical layering of production, and diversity of products. As our
component of this interdisciplinary project, this study will establish a comparative Life Cycle Assessment
to characterize environmental implications of a farm’s transition from a corn-soybean rotation to a
perennial polyculture cropping system. Data will be gathered from a 50 acre start-up farm as well as the
established farms, relevant literature, and interviews with farmers. The main objective is to characterize
the environmental implications of a transition from annual cropping to perennial. It is expected that the
long term implications of this transition to a multifunctional polyculture system will yield reduced runoff
flow, reduced pesticide concentrations, increased soil carbon retention, and improved surface and
groundwater quality.
Minmin Liu
Assessment of drinking water disinfection by using flow cytometry
Disinfection is an important process to control microbial risk of drinking water. Chinese standard method
to evaluate disinfection is plate culture method, which has its limitation. Flow cytometry along with
fluorescent probes can count bacteria one by one fast and accurately. This method only costs 3 hours
and can detect most kinds of bacteria. It is significant to choose proper fluorescent probes.
New SYTO9-CTC staining protocol is established. Steps are 1) mix sample with 10% volume R2A culture
medium and CTC fluorescent probe (2mmol/L); 2) incubate sample in 37℃ without light for 2.5h; 3) add
SYTO9 stain (1.5µL/mL) and incubate for 5min; 4) detect sample with flow cytometry. Use FL3 channel
as trigger, PMT voltage for FL1, FL2, FL3 channel are 4.5, 4.5 and 6.5V.
SYTO9-PI staining protocol could separate membrane intact bacteria with membrane ruptured. When
chlorine concentration is 1.0mg/L and contact time is 30s, 97% E.coli lost membrane permeability and
S.aureus signals disappear. Chloramine disinfection has the same results but the process is slower. But
39
this protocol can not describe UV disinfection because bacteria signals only separate when the UV dose
comes to 200mJ/cm2.
Use SYTO9-CTC to stain bacteria treated by chlorine and chloramine, it is found that bacteria with
ruptured membrane are still metabolic and viable. SYTO9-CTC staining protocol could evaluate UV
disinfection. Bacteria metabolism rate will slow down after UV exposure;there is a logarithmic relationship
between them. 40mJ/cm2 dose UV responds to 80% metabolic E.coli. Medium pressure UV has more
significant disinfection than low pressure UV.
Valerie Bauza
Identifying key drivers of successful national sanitation plans in low- and middle-income
countries
Globally, 2.5 billion people still lack access to improved sanitation facilities. Improving national sanitation
plans, including how sanitation services are managed and sanitation policies are implemented, is critical
for improving sanitation access. However, as of 2014, less than one-fourth of low- and middle-income
countries had sanitation plans that were funded, implemented, and regularly reviewed. Human and
financial resource constraints are often cited as major factors impeding greater improvements in the
sanitation sector, but evidence-based policy decisions related to sanitation are lacking. This poster
presents the analysis of associations between national policy and capacity characteristics with sanitation
access improvements over time for 38 low- and middle-income countries. The analysis uses data from
the UN-Water Global Annual Assessment of Sanitation and Drinking-Water reports and the World Health
Organization/UNICEF Joint Monitoring Program for Water Supply and Sanitation datasets.
Recommendations will be made regarding specific policy components and country capacity resources
that appear to be the strongest drivers of improvements in national sanitation access.
Conghui Huang
The effect of biofilm roughness and hydrodynamic condition on particle attachment in COMSOL
Biofilms grown on the pipe surface can be a threat to drinking water safety because it can accumulate
and release pathogens. However, factors contributing to pathogen accumulation and detachment are still
under investigation. To explore the role of biofilm roughness and pathogen transport, we experimentally
quantified adhesion of Legionella pneumophila on simulated drinking water biofilms, and conducted
simulation of particle deposition on simulated biofilm surface obtained from cross-sectional grown biofilm
40
in lab. Biofilms used in this study were grown from simulated drinking water for different time period and
thus different roughness, which was determined by OCT. To further exploring the mechanisms of how
roughness controls adhesion, we also conducted particle- tracing simulation using COMSOL
Multiphysics. Relatively rough and smooth biofilm profiles obtained from OCT images were used in
simulation of particle deposition, and adhesion of particles under same hydrodynamic conditions used in
Legionella adhesion experiments was quantified. The results revealed that surface roughness creating
local hydrodynamics facilitate the interception of particles with surface roughness, thus increase particle
adhesion. The simulation results agreed with experimental results. The possible application from this
study can be modification in biofilm monitor and treatment to reduce the risk of potential bacterial
exposure from drinking water distribution system.
Anshoo Narula
Feasibility of Recharge shafts/Injection wells for groundwater recharge in Patan district, Gujarat,
India
The poster will be based on a reserach paper I published in International Journal of Advanced Research
in Engineering and Applied Sciences on the topic "Feasibility of Recharge shafts/Injection wells for
groundwater recharge in Patan district, Gujarat, India" . For the industrial development, agricultural &
economic growth the demand of groundwater has increased in north Gujarat alluvial plain. The
groundwater draft exceeds the groundwater recharge resulting in over exploitation of groundwater
aquifers. This has resulted in continuous decline in water levels and reduction in the yield of the tube
wells. Due to poor rainfall reliability and recurring drought conditions, the area could never recover the
deficit of water extracted from groundwater resources. The artificial recharge to groundwater can only
sustain the water levels or can arrest the rapid depletion of groundwater rate. The part of Patan taluka in
Gujarat, India is selected for the construction of artificial recharge structures near the large storage village
ponds. It is proposed to construct artificial recharge structures in seven villages of Patan taluka near
these village ponds. The recharge potential is calculated taking 40 rainy days taking average rainfall as
770mm. If the recharge shaft is connected to the ponds at a depth, it is able to utilize the
storage of ponds and recharge potential can then be calculated for a period of 180 days (pre-monsoon
and post-monsoon period). Thus calculating the runoff potential of seven recharge structures and
considering the catchment of the area, the plan is considered
feasible for recharge in seven villages of Patan Taluka.
Zhongwen Ren
41
Airport-related air pollution
Now a day, because the increasing air pollutants risks on human health, more and more scientific
community and governments pay attention on how to improve poor air quality. Moreover, air pollution can
also decrease visibility and damage materials in buildings. As the rapid growth of air transport volumes,
people attract a really high level of interest in the airport emissions(AEs). The one of major source of
emission at an airport is aircraft exhaust. There are also many other sources which are presenting in
modern airports and emitting air pollutants. For example, there are large fractions of particulate matter
created by the air flow from the aircrafts. In addition, airport ground service equipment (GSEs) such as a
large number of passenger buses, baggage and food carriers, cleaning and lavatory services machines
also can emit the pollutants and impact the air quality. Additional sources may also be present at airports,
including high-temperature hot water generators, emergency generators and boilers that service both
terminals and support buildings. Moreover, because large airports are always located near to the big city,
they have a huge impact on the environment that a lot of people lived and affect for the human health.
The goal for this paper is to describe the research on aircraft and airport-related emissions, in order to
summary key characteristics for airport-related pollutants and the impact on air quality.
Junhui Liao
Application of Standalone Down-flow Hanging Sponge Reactor for Food Processing
Wastewater
Standalone Down-flow Hanging Sponge (DHS), an aerobic biological reactor, is studied to find the
possibility and performance for treating high organic loading food processing wastewater on site. The
research objective is to treat the wastewater to meet the municipal sewer discharge standard over long
term operation. Hydraulic retention time (HRT), additional nutrient loading and pH range are all the
objective parameter that this research is aiming to define in order to achieve the ultimate TOC and COD
removal performance for this reactor. Three DHS chains were established by using 30 sponges each and
saturated with sludge solution before hanging one by one as a chain. Reactors were feeding by synthetic
wastewater(1000 mg/L TOC, 45mg/L total nitrogen and 15mg/L total phosphorus). . pH and HRT are
keeping adjusting according to the effluent water quality. So far with 13 hours HRT and pH 9 the TOC and
COD removal rate can achieve 90%
Fangqiong Ling
42
Core-satellite model and seasonal dynamics in water meter biofilms of drinking water
distribution systems
Background: Drinking water distribution system is an important part of urban infrastructure, and the
microbial communities enclosed in the system are an important component of the built-environment
microbiomes. Examination of the biofilm communities has traditionally based on sampling on certain
points in the system. This study aimed to represent the diversity of biofilm microbial communities in a
drinking water distribution system (DWDS) with a spatio-temporal design and examine their response to
environmental factors.
Methods: The model system for this study was a mid-size distribution system that delivers conventionally
treated water from central Illinois groundwater. Household water meters (n=213) were used as sources of
biofilms, which allowed spatial and temporal replication over a 2-year time span. Microbial communities
were analyzed via 16S rRNA gene pyrosequencing. Sequences were processed with MOTHUR, and an
OTU-based analysis was conducted to compare biofilm and planktonic microbial communities.
Hypothesis testing based on similarity matrix was conducted with PERMANOVA and ANOSIM.
Results: Positive correlation between local abundance and regional occupancy was observed, and thus
core populations were defined in light of a “core-satellite” model. These core populations are low in
numbers of OTUs, but occupied the majority of sequences. Hypothesis testing on community similarity
indicates that seasonal variation explained the most of the variation. Key OTUs corresponding to
seasonal variation were further identified, suggesting the presence of cyclic fluctuation in core
communities.
Conclusions: Our findings indicate that seasonal variation is important in the community dynamics of
DWDS biofilms. The core-satellite model is useful in understanding a spatially-expansive water system.
The results contribute to the scholarship of “built environment microbiome” and shed light on ecology-
guided monitoring of drinking water systems.
Yida Fang
Biological and Biologically Mediated Abiotic Transformation of Contaminants of Emerging
Concern in Anaerobic Soils
Freshwater consumption and scarcity leads to a more frequent usage of wastewater for agricultural
irrigation in the effort to reduce water cost as well as nutrient cost. The presence of a wide range of
pharmaceuticals presented in wastewater has raised concerns due to such application. Because majority
of them are not regulated by government agencies, many of the pharmaceuticals are able to accumulate
in plants roots that eventually end up to human consumption. In this project, the fate and transport of four
43
commonly used pharmaceutical and personal care products (PPCP), Sulfamethoxazole (antibiotics),
Carbamazepine (anti-epileptic drug), Iopromide (contrast medium), and Norfloxacin (antibiotics), are
observed under various terminal-electron accepting processes (TEAP), such as nitrate, sulfate, and iron
(III) reducing environment. The degradation process of the four PPCPs is performed in lab scale reactors
that have a 3:1 water to soil ratio. LC tandem MS is used to detect the exact concentration change of the
PPCPs throughout a period of time. Moreover, the daughter products of each parent compound after their
degradation are also predicted using LC – MS. By predicting the daughter products, the specific
functional group that triggered the PPCPs oxidation/reduction reaction is identified, therefore, providing a
basic understanding of the PPCPs degradation pathway in anaerobic soil.
Kia Alexander
Assessing the environmental impacts of agricultural intensification in Sub-Saharan Africa – an
analysis of soybean development in northern Ghana. The US Agency for International Development’s (USAID’s) Soybean Innovation Lab (SIL) is an applied
research for development project employing scientific and socio-economic research efforts to enhance
the production and utilization of soybean in small-holder farming communities in Sub-Saharan Africa.
The environmental assessment of SIL’s work aims to develop a mechanistic understanding of the multi-
scale environmental impacts of soybean agricultural development, which will enable us to make
agricultural management recommendations supporting a transition toward increased food security that is
consonant with long-term environmental protection goals.
In the growing field of research on the environmental impacts of agriculture, few studies have focused on
the impacts of tropical agriculture, which varies markedly from temperate agriculture due to differences in
temperature, soil, and hydrologic regimes. This study provides an opportunity for unique insight into the
influences these conditions have on the environmental impacts of agriculture.
The direct, local environmental impacts of tropical soybean development will be assessed through
environmental quality monitoring at small-holder farms and at SIL’s soybean research site in northern
Ghana. Parameters to be assessed include air, water, and soil quality metrics, and direct and indirect
exposure of humans to agricultural toxins. Broader potential impacts, including land use change,
eutrophication, and effects on greenhouse gas emissions, will be assessed through an agro-
environmental life cycle assessment and the monitoring of long-term trends.
The project is in the preliminary data collection stage. Initial data collection from collaborating researchers
and from visits to the research site and plots of smallholder farmers are being used to inform the long-
term data collection plan for the environmental assessment.
44
Jerry Hsu
Electric field disinfection
Electric field disinfection is a new way to kill or disable microorganisms so that they cannot endanger
human health. Some bacteria can be harmful to human health when intake on high density. And human
sterilize their tableware and living environment to make sure that they don’t affect our bodies. Electric field
can be used to perform this task.
Electric field disinfection can be widely used on air conditioners, air-cleansing machine, and to sterilize
lab equipment. Recent research have proved that it’s more effective to disinfect bacteria living on solid
media, like tables, floors, etc., and not relatively efficient on killing air-borne species. But due to its area
effectiveness, electric field can be used in wide range of media.
Since electric field disinfection doesn’t require temperature and pH change of the media, it doesn’t
change the majority of the chemical reactions in the media. Many media required for disinfection are
coupled with tons of chemical reactions, and are easy to be halted if temperature or pH changes. In most
of the cases, disinfection treatment process is isolated from other treatment processes. After disinfection,
pH and temperature are adjusted back to the required state for further chemical reactions to occur.
Electric field disinfection can proceed simultaneously with other chemical reactions, thus provides us with
a new way to reduce cost for disinfection by saving the money for additional tanks and supplies to adjust
the medium back to it’s formal state.
Yang Song
Arsenic Removal via Bone Char Filtration
Arsenic in drinking water is strictly regulated by USEPA because its probable health effects. One way to
remove arsenic in the drinking water is via bone char. The bone char is porous, black, granular material
produced from charring animal bones. Pretreatment is required to convert As(III) to As(V). Common
oxidants include permanganate, peroxide, atmospheric oxygen. To optimize the performance of removal,
the adsorption kinetic need to be studied. The study shows that optimum removal was achieved in pH
range between 9 and 13, contact time of 30 minutes and adsorbent dosage of 0.8 g/l. The removal is
usually higher for the lower initial arsenic concentration. The bone char combined with ion exchange resin
and membrane techniques is a powerful tool to remove the arsenic.
Minhao Lu
45
Radon, a non-negligible health risk
Radon is the most common radioactive element appears in people’s life. Because it’s colorless and
odorless, radon becomes an invisible but non-negligible health risk. According to USEPA, radon is the
second main cause of lung cancer after smoking, and the number one cause among non-smokers. Due
to radon gas’s high density, it may accumulate in the basement of one’s home, cause long-time low-
concentration exposure to radon. EPA recommends all house take a radon test in the lower part of their
house, and any house has a radon level higher than 4 pCi/L should fix their house to lower the Radon
threat. This poster is a literature review about the Radon’s radioactivity, risk to health, its common
distribution in US and general mitigation ways to lower the risk.
Erhu Du
Evaluating the impacts of an agricultural water market in the Guadalupe River Basin, Texas: An
agent-based modeling approach
Agriculture comprises about 80 percent of the total water consumption in the US. Under conditions of
water shortage and fully committed water rights, market-based water allocations could be promising
instruments for agricultural water redistribution from marginally profitable areas to more profitable ones.
Previous studies on water market have mainly focused on theoretical or statistical analysis. However,
how water users’ heterogeneous physical attributes and decision rules about water use and water right
trading will affect water market efficiency has been less addressed. In this study, we developed an agent-
based model to evaluate the benefits of an agricultural water market in the Guadalupe River Basin during
drought events. Agricultural agents with different attributes (i.e., soil type for crops, annual water diversion
permit and precipitation) are defined to simulate the dynamic feedback between water availability,
irrigation demand and water trading activity. Diversified crop irrigation rules and water bidding rules are
tested in terms of crop yield, agricultural profit, and water-use efficiency.
The model was coupled with a real-time hydrologic model and run under different water scarcity
scenarios. Preliminary results indicate that an agricultural water market is capable of increasing crop
yield, agricultural profit, and water-use efficiency. This capability is more significant under moderate
drought scenarios than in mild and severe drought scenarios. The water market mechanism also
increases agricultural resilience to climate uncertainty by reducing crop yield variance in drought events.
The challenges of implementing an agricultural water market under climate uncertainty are also
discussed.
46
Cunqian Li
Indoor Air Quality
Indoor air quality is essential to human health. Studies show that people spend over 90% of their lifetime
indoor. Lower air exchange rate in indoor environment can accumulate the air pollutants. According to
U.S Environmental Protection Agency (EPA), poor indoor air quality is been regarded as a top
environmental health risk. The poster will discuss the source of pollutants such as dust, molds, radon,
smoke and fumes, or VOC and their potential harm upon human beings. The poster will also introduce
the mechanism of several indoor air quality control techniques such as filtration, ventilation, adsorption,
and absorption. The poster will compare several indoor air quality control devices including photo catalytic
oxidation air purifier, electrostatic precipitator, high efficiency particulate air filtration, and active carbon by
their advantage and disadvantage.
Wen Tang
Sustainable Design of Microalgae Reactor for Biomass Production
The objective of this project is to design a closed microalgae system using secondary treated municipal
wastewater as nutrient resource in EI Paso, TX. The aim of the design is to achieve the annual biomass
production goal of 100,000 kg and maximize the profit with minimum environmental impact. Life Cycle
Assessment (LCA) using SimaPro and Life Cycle Cost Analysis (LCC) are conducted to evaluate different
microalgae candidates (Chlorella vulgaris and Scenedesmus obliquus) and determine the optimal value
of critical design parameters (recycle ratio and diameter of the tube). The results show that when using
Chlorella vulgaris and with the tube diameter of 0.25m and recycle ratio of 1.9, the unit cost of biomass
production reaches the lowest value and the environmental impact is minimum. However, since the cost
is much higher than the income, the project cannot be profitable, which is consistent with the conclusions
of other researches. The two main contributors of total cost are the tubes and electricity.
Hao Chen
Adsorption Mechanisms of Thallium(I) and Thallium(III) by Titanate Nanotubes: Ion-Exchange
and Co-Precipitation
47
Owing to hydrothermally-synthesized titanate nanotubes (TNTs) have unique physicochemical
characteristics, large surface area, charged surface and small sizes [1], this research indicated that TNTs
show great capacities to absorb thallium ions, which is highly toxic especially to mammals if it is in high
concentration, and the amount of thallium has increased with the development of industrialization [2-3].
Two primary oxidation states of thallium are Tl(I) and Tl(III). In this research, the Langmuir mode can best
fit the adsorption of Tl(I) using TNTs. However, for Tl(III), when the Tl(III)’s concentration is low, the
adsorption is mainly ion-exchange with Sodium ion, and Tl(III) will co-precipitation with TNTs forming
Tl(OH)3 if the concentration of Tl(III) is high [4]. What’s more, the TNTs’s abilities to adsorb Tl(I) and Tl(III)
show positive correlation with pH. Finally, this research also illustrates TNTs can be reclaimed, which
means TNTs can have a better adsorption ability for thallium again after using HNO3 for desorption and
NaOH for regeneration [4]. In this circumstance, TNTs can be as a potential material to remove thallium in
the wastewater treatment plant.
Rishabh Shah
Hygroscopicity and cloud condensation nuclei (CCN) activity of biomass-burning aerosol
Primary organic aerosol (POA) particles can act as CCN and indirectly affect climate by altering the
microphysical properties of clouds. Of the total POA emissions from combustion, 88% is estimated from
biomass burning. Anoxic conditions in the core of a burning piece of biomass lead to emission of organic
carbon (OC) as gas and subsequent condensation into aerosol particles. Several atmospheric processes,
collectively termed ‘aging’, change the hygroscopic nature of OC. The purpose of this research is to
identify and quantify the reactions that affect the climate-relevant properties of these ubiquitous aerosols
so that their properties at emission can be explicitly linked to direct and indirect radiative forcing. We
conducted bench-scale experiments on OC aerosol to determine its hygroscopicity and changes in CCN
activity upon aging. OC aerosol was aged with controlled concentrations of anhydrous NH3 and O3, two
common reactive trace gases in the lower atmosphere. The relative humidity (RH) during aging was
controlled to simulate RH conditions in the lower atmosphere (5-85%), as water taken up by particles may
participate in the aging reactions. We use the activation diameter (D50), the diameter at which 50% of the
total aerosol particles are activated, as an indicator of CCN activity. A reduction in D50 implies greater
CCN activity. We measured the size growth factors of fresh OC aerosol at RH ranging from 40 to 90%.
Two hygroscopic tandem DMA tests with κ-Köhler model fits gave similar results of κ = 0.08±0.005 and κ
= 0.07±0.018. All CCN measurements were done at a supersaturation of 0.3%. OC aged with 10 ppmv
NH3 had minimal change in D50, less than 5% reduction, for either low and high RH during aging (5%
and 85%, respectively). OC aged with high concentration of NH3 (875 ppmv) at 70% RH had a 23%
decrease in D50. Aging with 100 ppbv O3 (RH < 5%) resulted in no change in D50 of the OC, although
48
the slope of the activation curve was steeper than that of fresh OC. This finding indicates that activation
behavior is more consistent across the particle population after aging.
Trang Vu
The formation of nitrogenous disinfection by-products from the reaction between
dichloroacetaldehyde and monochloramine
A mandatory step in a drinking water treatment plant is disinfection in which a powerful oxidant was
employed to remove harmful pathogens threatening the human health. However, some by-products from
this process, which are proved to be toxic, become one of important health issues. Disinfection by-
products (DBPs) are formed from the interaction of the disinfectant (e.g. chlorine or chloramine, etc.) and
the precursors naturally occurring in water such as bromide, aldehyde, and other organic matters. Only
DBPs produced by chlorination such as trihalomethanes (THMs) and haloacetic acids (HAAs) have been
studied and regulated. Newly proposed regulations with stricter standards of these compounds lead to a
switch to alternative disinfectant (e.g. ozone or chloramines), and thereby can promote the formation of a
new DBP class. On the other hand, the researches on nitrogenous DBPs, which contain nitrogen in their
structures, have not been conducted widely though their toxicity is much higher than the regulated
groups. The purpose of this study is characterizing the formation pathway of N-DBPs from the reaction
between dichloroacetaldehyde and monochloramine. The results suggest that dichloroacetonitrile and
dichloroacetamide, two prevalent compounds among N-DBP group found in drinking water, were actually
produced from this reaction. In this work, the equilibrium rate constants of the reversible reaction between
dichloroacetaldehyde and monochloramine were also estimated.
Yalin Li
Model Comparison and Modification for Algal Hydrothermal Liquefaction
With the current climate changing background and increasing research interests in renewable energy,
squeezing energy from algae has raised great attention. Unlike terrestrial plants like corns and sugarcane
that are required to produce ethanol, a typical first-generation biofuel, algae can be cultivated in aquatic
environments like sea and wastewater. The reduction in desire for land, especially farmland, may be a
great progress towards the end of paradox choice between “Feed the poor, or the rich’s car?” Thus
producing biocrude and biodiesel, which are now commonly referred to as second generation biofuels,
has become a “hot spot” for recent work. In order to convert algae into biofuel that can be later upgraded
49
as a potential substitute for fossil fuel, an emerging technology, Hydrothermal Liquefaction (HTL) can be
employed. Several models have been put forward to illustrate the relationship between crude algae
composition and the HTL yield, but more work is required to determine the accuracy and applicability of
these models, which is exactly what my current research focused on.
Fransico Mena Gonzalez
Modeling the Cloud Condensation Nuclei Activity of Aerosols from Residential Biofuel
Combustion
Residential biofuel combustion is an important source of aerosols and gases in the atmosphere. The
change in cloud characteristics due to biofuel burning aerosols is uncertain, in part, due to the uncertainty
in modeling the added number of cloud condensation nuclei (CCN) from biofuel burning. We provide
estimates of the CCN activity of biofuel burning aerosols by explicitly modeling plume dynamics
(coagulation, condensation, chemical reactions, and dilution) in a young biofuel burning plume for the first
15 seconds after emission. We found that aerosol-scale dynamics only affect activation during the first
few seconds of evolution, after which the CCN efficiency reaches a steady state. The condensation of
semi-volatile species is the main factor driving aerosol activation; dilution rate and volatility of plume
gases had no significant effect. Our results provide a theoretical basis from which one can improve
estimates of the aerosol effects on clouds.
Recommended