Upload
india-water-portal
View
124
Download
1
Tags:
Embed Size (px)
Citation preview
ECAR: A scalable low-cost
arsenic remediation technology
Prof Joyashree RoyProfessor of Economics, Jadavpur University (Kolkata),
Coordinator, Global Change Programme at Jadavpur
University
Dr. Susan AmroseProject Scientist, University of California, Berkeley,
Lawrence Berkeley National Lab - USA
(Prof Ashok Gadgil, Team Leader)
Mr. RS RajanManaging Director, Luminous Water Technologies Pvt. Ltd
Dr. Suresh SisodiaChief of Technology, Luminous Water Technologies Pvt. Ltd
1
With grateful acknowledgement of support from:
The Andrew and
Virginia Rudd
Family Foundation
Arsenicosis causes painful skin lesions, lower IQ for children,
gangrene and amputation, cancers, and death (+ other effects) 3
Symptoms of arsenicosis begin in early 1990s
>95% of these failed within 1 year*! *Ph.D. Thesis, Abhijit Das, Jadavpur University, 2012
Need: a Sustainable Technology System
= Effective, Robust, Financially Viable, Locally
Affordable, Scalable, and Socially Embedded
• WaterHealth technology was also invented and developed at
the Gadgil Lab, University of California, Berkeley
• Sold water for 1 rupee for 10 Liters (in 2007)
• Affordable + Financially viable Sustainable
Andhra Pradesh, India
A promising scale-up model for this problem
is based on WaterHealth International
WaterHealth Center in Aufman village, Ghana
6
ECAR was designed to fit within a
sustainable, scalable system
ECAR = Electro-Chemical Arsenic Remediation
P, Si, As sorb to
Fe-III-Oxides
Fe-II is produced,
becomes Fe-III
and precipitates
as Fe-III-Oxides
then settle out
as sludge7
Top view of dosing tank
Settling Tank
5500 liter per day ECAR reactor built in Mumbai
Dosing Tank
Dhapdhapi High School - West Bengal ECAR System
This reactor was tested at Dhapdhapi High School
(South 24 Parganas, West Bengal) 2012 – 2013
10
From field operation, we know ECAR is:
Locally affordable
– consumables Rs 12 – 27/m3 (< 3 paise/L)
No regeneration, No imported adsorbent, No pH adjustment
Simple supply chain – steel plate, non-ferric alum (all local)
Minimal sludge (~250 grams/m3), well stabilized in concrete
Highly effective in real groundwater even with intermittent
power supply
– consistently < 4 ppb arsenic and < 0.3 ppm iron
Waste sludge is minimal and
non-hazardous per US EPA standards
• Passes TCLP (US EPA
hazardous waste test)
• Passes TCLP also in
crushed concrete
– 0 ppb arsenic in leachate
11
ECAR sludge embedded in concrete
ECAR consistently delivered < 4 ppb As in field
12
Project Website:
http://arsenic.lbl.gov
13
Supplemental Slides Follow
14
> 10 million tubewells installed in Bangladesh alone
Massive switch to tubewells accomplished in
Bangladesh and West Bengal (1970-2000)
15
> 70 million people are being poisoned in Bangladesh
One estimate is 20% of adult deaths are now from arsenic** Argos et al, Lancet 2010
Arsenic is so toxic that
WHO-MCL is 10 ppb
Bangladesh water has
levels up to 2000 ppb!!
This led to the largest mass poisoning in
human history!
West
Bengal,
India Bangladesh
arsenic-
contaminated
arsenic-
safe
(Map Credit: Chowdhury et al., 2000, Environ. Health Perspect)16
ECAR reduces arsenic below the WHO recommended
level in synthetic groundwater with up to 3000 ppb As
50% AsIII
50% AsV Iron dose (mg/L)
WHO-
MCL
ECAR reduces arsenic below the WHO recommended
level in real groundwater from Bangladesh, Cambodia
ECAR is backed with robust new science
Electrochemical Arsenic Remediation: Field Trials in West Bengal, Amrose,
Bandaru, Delaire, van Genuchten, Dutta, Deb Sarakar, Orr, Roy, Das,
Gadgil, Science of the Total Environment, in press, 2014.
Structure of Fe(III) precipitates generated by the electrolytic dissolution of
Fe(0) in the presence of groundwater ions, van Genuchten, Pena, Amrose,
Gadgil, Geochimica et Cosmochimica Acta, 127 :285–304, 2014.
Arsenic removal from groundwater using iron electrocoagulation: effect of
charge dosage rate, Amrose, Gadgil, Srinivasan, Kowolik, Muller, Huang,
and Kostecki. Journal of Environmental Science and Health, Part A,
48(9):1019-1030, 2013.
Modeling As(III) oxidation and removal with iron electrocoagulation in
groundwater, Li, van Genuchten, Addy, Yao, Gao, and Gadgil.
Environmental Science and Technology, 46(21):12038–12045, 2012.
Removing arsenic from synthetic groundwater with iron electrocoagulation:
An Fe and As k-edge EXAFS study, van Genuchten, Addy, Pena, and
Gadgil. Environmental Science and Technology, 46(2):986–994, 2012.
Social embedding begins with local partnerships,
reputation building, and community ownership
Community input and feedback has been
prioritized throughout the process
We’ve partnered with BUET (Bangladesh) and Jadavpur University (Kolkata)
to conduct workshops, in-depth case studies, interviews, and surveys
At least 230,000 people
exposed to arsenic levels
above the recommended MCL
limits
Arsenic affects hundreds of thousands of people in
California, disproportionately affecting the poor
In 2008, California revised the
Arsenic MCL from 50 ppb to
10 ppb.
- Many systems are now
out of compliance
As > 10 ppb
As < 10 ppb
Source : http://www.cacoastkeeper.org/
Pathogens (e.g. rotavirus, Shigella) recently detected in
tubewells in the region (Ferguson et al, 2012)
Initial results for ECAR E.coli (4-log) and
MS2 virus (6-log) removal
0
1
2
3
4
5
6
0 50 100 150
Log –R
em
ova
l
Iron dose (mg/L)
MS2 (ECAR)
MS2 (2LFh)
E.coli (ECAR, SBGW)
4-log removalthreshold
23
Our team won in 2013 the top (Creativity) 5th Prince Sultan
Bin Abdulaziz International Prize for Water
ECAR offers many advantages over
competing arsenic-remediation technologies
25