Tested Technologies for Wastewater Treatment

Tested Technologies for

WastewaterTreatment

Wastewater eHANDBOOK

Precise detection of all process properties

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TABLE OF CONTENTSReally Get Bugged 5

Biological treatment can handle many industrial wastewater streams

Report Dives into Water Security 9

Several key points emerge from the record number of responses

Combine Environmental Stewardship and Bottom-Line Manufacturing 12

Wireless sensors and the network can reduce expenses

Improve Wastewater Temperature Stability 17

Direct steam injection can boost anaerobic digester system performance

Additional Resources 20

AD INDEXKrohne • krohne.com/waterandwastewater 2

Pick Heaters • www.pickheaters.com 8

VEGA • www.vega.com/vegapuls 11

Yokogawa • www.yokogawa.com/us 4

Wastewater eHANDBOOK: Tested Technologies for Wastewater Treatment 3

www.ChemicalProcessing.com

http://krohne.com/waterandwastewater

Let our experts guide your digital transformation journey

www.yokogawa.com/us

Bad data ruinsgood intentions

Accurate and reliable field instruments

provide the foundation necessary for a

successful digital transformation.

For over 60 years, Yokogawa has earned customer confidence by focusing on accuracy, reliability, and serviceability. The addition of turbidity and chlorine measurements to the SENCOM 4.0 platform provides deeper Total Insight and enhanced value for water quality and a sustainable water cycle in emerging, smart city applications.

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Really Get BuggedBiological treatment can handle many industrial wastewater streams

By Dirk Willard, Contributing Editor

BP management had its doubts. John

Eastman’s proposal was to eliminate

NH3 from wastewater at the firm’s

chemical plant in Lima, Ohio, using a two-

stage bioreactor. It started with aerobic

nitrosomonas bacteria converting NH3 to

nitrites in filter substrates, and then used

anaerobic denitrifying bacteria to convert

the nitrites to N2. In the second stage, these

bacteria were to be grown in large ponds.

The pilot plant worked flawlessly and we

developed a front-end loading (FEL-3)

scope and budget for the process. (Ade-

quate front-end loading is crucial for any

project; see “Don’t Flub Front-End Load-

ing,” http://goo.gl/cuGZc5.)

Think of what this means! Instead of

an elaborate staged process requiring

maintenance staff, bugs are your unit

operation. There’s a word to describe

this: nifty.

Let’s consider the pros and cons of bio-

logical wastewater treatment for heavy

metal removal and elimination of hydro-

carbons. First, most all the heavy metal

winds up as a solid; this, in itself, is highly

useful because the metal is removed from

the wastewater. Aerobic treatment excels

at converting compounds of carbon,

oxygen, nitrogen and phosphorus into

N2, CO2, phosphates and H2O. Anaerobic

digestion of materials produces methane,

Using bugs as a unit operation is nifty.



enabling food-processing and similar

wastes to become a source of fuel gas.

The waste composition and type of reactor

determine the most-appropriate organism.

Aerobic reactors use algae and bacteria.

Anaerobic reactors rely on sulfur-reducing

bacteria (SRB) and fungi. Anaerobic reac-

tors minimize sludge and loss of chemicals

to the atmosphere but tend to require

processing in batch because of slow reac-

tion times.

Aerobic fluidized bed bioreactors fre-

quently offer the best economics — but

require skilled operators. Often, anaer-

obic and aerobic reactors are paired in

series, as in the NH3 cleanup process at

Lima. Some research has shown that an

anaerobic treatment stabilized and pro-

vided nutrients to the bugs in an aerobic

process that followed. This research

tends to be project-specific — so it’s

sensible to conduct a pilot study before

full implementation.

Studies in Poland, Italy and elsewhere con-

cluded that heavy metals are effectively,

but slowly, removed from wastewater in

an anaerobic environment using SRB or

fungus. The resultant heavy-metals-laden

sludge, of course, then requires careful

disposal. A fast aerobic reaction involving

algae has successfully treated wastewater

containing copper and cadmium — remov-

ing 98% of the Cu and 100% of the Cd.

Waste removal efficiencies generally

depend upon the relative proportion of

different bugs as well as feed stability. Pro-

moting the growth of the best species may

require trace nutrients — e.g., FeIII is added

to enhance anaerobic disposal of toluene.

The heavy metal or organic present also

impacts efficiency. Parameters controlling

digestion include: pH, which usually is low

— SRB raise the pH to neutral; tempera-

ture, which generally should stay between

60° and 100°F — the water can’t be frozen

or boiling; initial concentration of the metal

or organic — low concentration discour-

ages bug growth while extremely high

concentration kills bugs; and nutrients and

their transportation. Consistency is cru-

cial to growing and maintaining the bugs

you want.

With hydrocarbons, biological reactions are

highly efficient in destroying oxygen and

nitrogen components. However, chlorinated

compounds, like dioxins, merely are con-

verted to materials such as vinyl chlorides

The waste composition and type of reactor determine the most-appropriate organism.



or dichloroacetate that may be nearly as

bad or perhaps even worse than the original

waste. This is strong argument for anaero-

bic processing.

One refinery study showed the best results

with a carbon/nitrogen/phosphorus mole

ratio of 100:5:1.The actual ratio may be less

important than the ratio’s stability.

Heavy metals like mercury that are mixed in

organics often inhibit biological growth of

the best organisms. An additional problem

is that the heavy metal is converted to an

organo-metal that animals and plants can

readily absorb. (“Consider the Consequences

of Chemistry,” http://goo.gl/cvKWXA, looks

at one unfortunate example — people suffer-

ing health effects caused by wallpaper dyed

with Prussian Green.)

For additional information, check:

• “Enhanced Remediation of Chlorinated Sol-

vents from Contaminated Solvents Using a

Bioreactor System,” http://goo.gl/tfqjJl; and

• “Trichloroethylene Pathway Map,”

http://goo.gl/fI3m21.

DIRK WILLARD is a contributing editor for Chemical

Processing. Email him at [email protected].

www.chemicalprocessing.com/podcast/process-safety-with-trish-and-traci

Trish Kerin, director of IChemE Safety Centre, and Chemical Processing’s Traci Purdum discuss

process-safety issues offering insight into mitigation options and next steps.

From questioning if inherently safer design is really safer to lessons learned from significant

incidents, these podcasts have one goal:

To ensure workers return home safely after every shift.

PROCESS SAFETY

With Trish & Traci



Dependable and Energy Efficient

Direct Steam Injection Heaters

for Industrial Wastewater Heating

®

Contact us to find out more about the advantages of Direct Steam Injection

• 262-338-1191 • Email: [email protected] • www.pickheaters.com

Temperature control in chemical industry applications including wastewater heating requires

absolute precision, and only Pick Direct Steam Injection Heaters can provide it. That’s because

Pick’s exceptional temperature control automatically holds discharge temperatures to

extremely close tolerances — within 1°C — while providing rapid response to changing

process conditions.

Pick also eliminates costly BTU losses with 100% energy efficiency. This alone can save you up

to 20% in fuel costs as compared to heat exchangers or steam sparging. In addition, Pick’s

compact design along with its ease of maintenance saves valuable space and reduces down

time. All this combined with the lowest sound level and water pressure drop in the industry

makes Pick Heaters the right choice for wastewater heating.

http://www.pickheaters.com

https://www.pickheaters.com/OffNav/Chem-Processing-Wastewater.htm

https://www.pickheaters.com/OffNav/Chem-Processing-Wastewater.htm

mailto:info1%40pickheaters.com?subject=

The latest water report from CDP,

London, details progress but also

stresses the need for ambitious action.

“A Wave of Change — The role of companies

in building a water-secure world,” released in

early March, summarizes information gath-

ered from 2,934 companies worldwide that

filled out the organization’s water security

questionnaire in 2020 — about a 20% uptick

in responses compared to 2019.

The organization, which acts on behalf of 515

investors worth over $106 trillion, emphasizes

that the private sector must play a crucial role

in building worldwide water security.

CDP draws several key conclusions from the

companies’ questionnaires:

• The cost of inaction is five times greater

than that of action. The firms risk more

than $300 billion in business value against

an estimated $55 billion cost to improve

and innovate around water use.

• Business models must fully integrate

water into strategies and ensure account-

ability for water targets at the highest

level. The report cites a number of com-

panies, such as BASF, transforming their

approaches. The Ludwigshafen, Germany,

chemicals maker notes: “Using CDP’s

water questionnaire as a framework has

helped us improve our comprehensive

water-management strategy to mitigate

water-related risks and capitalize on

opportunities.” This has spurred devel-

opment of sustainable “Accelerator”

products. The report devotes a full page

to the company’s efforts. (For details on

the diverse financial approaches for sus-

tainability efforts taken by some chemical

Report Dives into Water SecuritySeveral key points emerge from the record number of responses

By Mark Rosenzweig, Editor in Chief



companies, including BASF, with CDP’s

top ranking for water security, see

“Water Accounting Remains Fluid,”

https://bit.ly/3duY9QE.)

• Nearly two in three companies are reduc-

ing or maintaining water withdrawals.

The 64% of firms reporting such results

is up from 58% in 2019. Another, related

key performance indicator (KPI) also

rose: 64% of companies said they factor

in water availability at a basin/catchment

level into water risk assessments versus

48% last time. Likewise, 38% of companies

reported using climate-related scenario

analysis to inform their business strategy,

up from 33% in 2019. Six other KPIs for

water security didn’t budge much if at all.

• Only 4.4% of the firms are making

progress on their water-pollution-reduc-

tion targets.

Cate Lamb, global director of water secu-

rity at CDP, notes: “With a clear business

case for taking action on water risks,

we hope this report inspires companies

across all sectors to be part of this vision

and place water at the heart of your busi-

ness strategy — enabling you to not only

build resilience but also unlock strategic

opportunities...”

She adds: “...CDP is calling for all compa-

nies to develop ambitious targets to reduce

water withdrawals and eliminate water

pollution, including net-zero water targets.

Companies must take bold action now to

transform their business models.”

The benefits are substantial, Lamb under-

scores. “Companies that transform their

businesses and work to safeguard valu-

able water resources have the potential

to achieve both short- and long-term cost

savings, sustainable revenue generation,

and a more resilient future.”

You can download the 2020 report at

http://bit.ly/3bhWjl1.

By the way, in a CP poll, https://bit.ly/3C-

d4km1, almost half of respondents report

their sites have increased attention to water

resources in the past three years.

MARK ROSENZWEIG is editor in chief of Chemi-

cal Processing. Email him at mrosenzweig@

putman.net.

Water security efforts can provide substantial benefits to companies.



https://bit.ly/3Cd4km1

https://bit.ly/3Cd4km1

$981VEGAPULS 31

RADARULTRASONICIS THE BETTER

Compact 80 GHz level sensor with in-head display

www.vega.com/vegapulsAll advantages of the radar technology:

http://www.vega.com/vegapuls

Environmental stewardship plays

a key role in manufacturing. In

fact, manufacturers integrate their

productivity goals with those of quality,

health, safety and environment (QHSE) and

environmental social governance (ESG).

Strongly affected by these concerns are

facilities whose processes include water

treatment. To support community and

global environmental requirements, manu-

facturing design solutions must run parallel

with sustainability actions while supporting

smooth operational and maintenance sav-

ings (Figure 1).

As many manufacturing teams have dis-

covered, meeting environmental objectives

does not cause economic pain in startup,

operations or maintenance. Co-innovating

with manufacturers around the globe to

meet environmental challenges can lead

to improved environmental consciousness

while enabling strong business decisions to

reap profitable returns.

ADVANCES IN TECHNOLOGY STREAMLINE ENVIRONMENTAL STEWARDSHIPWater stewardship poses nontrivial chal-

lenges for manufacturers, for example,

meeting maintenance budgets while ensur-

ing consistent water intake and achieving

ideal temperatures in far-off holding ponds.

Because these stewardship activities will

continue to grow in importance, manu-

facturers must look to technology and

innovative solutions that will succeed now

and support them in the future.

Combine Environmental Stewardship and Bottom-Line ManufacturingWireless sensors and the network can reduce expenses

By Gerald Hardesty, Yokogawa



Accurate temperature, pressure and

vibration sensors are some of the keys

to maintaining not only efficient and safe

manufacturing processes but also a sus-

tainable environment. Teams that have

considered wireless devices for remote

areas might have found prohibitive costs

of technologies that do not conform to

their practices. However, new market solu-

tions pair high-quality sensors with open

network specifications that bring IIoT

affordability and enable efficiency toward

digital transformation. In the end, there is

no need to sacrifice either affordability or

data quality.

One example is the Sushi sensor, a small,

wireless pressure, vibration and tem-

perature sensor that monitors conditions

continuously and accurately over vast

distances. Small sensors deliver data in

tight-fitting remote situations to a hub

so that teams can track trends, detect

abnormal conditions early and help direct

troubleshooting activities efficiently. This

comprehensive condition monitoring leads

to predictive maintenance and helps set

maintenance priorities and reduce costs.

Preventive or time-based maintenance once

was the preferred solution for teams to

maintain equipment health. Now predictive

maintenance — using data and analysis to

predict when issues will arise — has been

found to save maintenance resources while

avoiding equipment issues. Rather than

sending technicians out on a schedule to

review equipment with no issues, predictive

maintenance combines sensor data with

machine learning and diagnostics to deter-

mine when conditions have changed and

require attention.

BALANCING SUSTAINABILITY WITH PROFITSFigure 1. Environmental stewardship does not have to come at a cost. Sustainability efforts can help to improve a company’s bottom line.



The process is streamlined

because a team member

does not need to travel to the

remote area to inspect condi-

tions (Figure 2). Often, minor

issues can be found and

solved before they become

significant, as might happen if

left to a monthly schedule.

Data is communicated via

the Long Range Wide Area

Network (LoRaWAN), a low-

power, wide-area (LPWA)

networking protocol. It is

ideal for conditions that

require accuracy but less

frequent collection rates, as

seen in intake and outflow

water treatment applications.

LoRaWAN’s bi-directional

communication, end-to-end

security and mobility can

enable sensor deployment

over six miles (10 km) from

the facility.

With the focus on meeting

environmental requirements,

teams must store gathered

data and be ready for an

audit. Whether the data is

analyzed and stored in the

cloud, a local network or

on-premise, solutions must

be versatile to fit the need.

Measurement data can be

sent from the Sushi sensors

via a LoRaWAN gateway to

Yokogawa’s SMARTDAC+

GA10 data logging software,

where artificial intelligence

(AI) analyzes operating con-

ditions and trends. The GA10

software alerts process

management system opera-

tors to changing conditions,

thus supporting predictive

maintenance. In some large

applications that require

more analysis and stor-

age, teams can choose a

CI server in place of the

SMARTDAC+.

PREDICTIVE MAINTENANCEFigure 2. The sensor gathers data, which the data logging software analyzes. Operators are alerted to any abnormality, allowing for early intervention before serious issues arise.



SAVINGS DELIVERED FOR ENVIRONMENTAL SUSTAINABILITYMany manufacturing facilities use water from

external natural sources as part of their prod-

ucts or processes, such as a cooling tower,

to remove heat from materials. Good water

stewardship includes proper methods of

collecting water from local resources, mon-

itoring the quality of the water returned,

eliminating negative impact on surroundings

and improving the resources.

Water taken from a local source enters the

facility supply pipe through a rotating filter

or screen to prevent materials and wildlife

from entering. Contaminants that accu-

mulate on the filter can reduce the water

throughput, jeopardize downstream opera-

tions and damage the filter.

Potentially far from the manufacturing

facility, the pressure at the water intake on

both sides of the filter must be measured

wirelessly to monitor the flow and assure

that adequate water enters the system to

preserve smooth process operation. The

physical distance from the facility makes

connectivity a challenge for some wireless

signal types and networks, so be sure to

account for this when selecting a sensor.

Pumps in these applications prove vital to

keeping water moving and the water treat-

ment process operating smoothly. Excessive

vibration in pumps indicates issues that can

lead to pump breakdowns. Too often, equip-

ment is either checked and monitored for

vibration levels via once-daily operator rounds

or not monitored at all. This lack of visibility

into equipment conditions can lead to unfore-

seen breakdowns, downtime and costs.

However, AI combined with the right sen-

sors can detect changes to the vibration

AI ANOMALY DETECTIONFigure 3. A developing issue was detected before any sign of it would have appeared in vibration data.



data before the vibration becomes a prob-

lem, as shown in Figure 3. Teams can detect

potential issues and dispatch a technician

before the damage becomes significant.

In addition, placing vibration sensors

throughout a water treatment system means

teams can improve their pump efficiency,

energy usage, environmental stewardship

and the team’s efficiency through condi-

tion-based monitoring. Installing vibration

can be easy if they are attached mag-

netically. Once the LoRaWAN network is

established, adding additional sensors is

simple and almost automatic.

Water flowing from a manufacturing pro-

cess to a local river might be used to keep

the process from overheating. Even though

the water is clean, thermal pollution can

have a devastating impact on the river eco-

system. In this situation, keeping the water

in a holding pond changes the ambient tem-

perature so slowly that the sensor does not

need to send measurements every second.

Some sensors can send data as often as

once per minute — or less frequently to

extend battery life. Many users have added

a recorder to display and document how the

water temperature reached a safe level.

Savings extend to a requirement for less

infrastructure in the field when the sensor net-

work’s long range allows the team to forego

an intermediate SCADA or backhaul network.

MOVING FORWARD TO FUTURE SUSTAINABILITYThe combination of remote sensors that

are economically and quickly installed,

data retrieved over a low-power net-

work, and information that is analyzed

and prepared for efficient decision-mak-

ing make the goal of water sustainability

more achievable.

While many sensors can provide impact-

ful information on their own, adding the

SMARTDAX+ GA10 software creates the

Yokogawa IIoT Plant Asset Management

Solution as the next step in providing

insight and analysis for maintenance

teams to make informed decisions. When

sensors and LoRaWAN networks are

combined with data-gathering and anal-

ysis solutions, data is efficiently stored,

informed decisions are made, and costs

are reduced.

As organizations complete their IIoT

solutions and prepare for future sustain-

ability challenges, open alliances — such

as the nonproprietary wireless protocol

LoRaWAN — encourage options for flex-

ibility. The LoRaWAN Alliance opens up

a host of interoperable tools from which

users can choose.

GERALD HARDESTY is emerging solutions manager at

Yokogawa Corporation of America, Newnan, Ga. E-mail

him at [email protected].



Numerous industrial processes gen-

erate organic wastes that require

treatment before they can be

reintroduced back into the environment.

Traditionally, these materials have been

buried in landfills, composted or deposited

into sludge ponds after the removal of haz-

ardous or inorganic materials.

Anaerobic digestion involves the natural

breakdown of organic waste materials by

biological microorganisms in the absence of

oxygen. Systems that incorporate anaerobic

digestion have several advantages, such as

simplicity of operation, low operating costs,

compact equipment size and low surplus

sludge.

As a bonus, these systems produce fuel and

energy. Anaerobic digestion has become

increasingly popular, as it is a green tech-

nology that reduces waste, generates

energy, cuts carbon emissions and recy-

cles waste materials safely back into the

environment.

ANAEROBIC DIGESTION PROCESSAnaerobic digestion systems operate on

the same principles regardless of the spe-

cific applications, although there may be

slight differences in system design based on

industry-specific requirements. As shown

in Figure 1, organic waste materials such as

industrial wastewater, wastewater biosolids,

food wastes and other organic materials

are placed into an anaerobic digester. The

digester combines the waste materials with

biological microorganisms and maintains

this mixture within narrow temperature

ranges to optimize bacteria growth, which

Improve Wastewater Temperature StabilityDirect steam injection can boost anaerobic digester system performance

By Phil Hipol, Pick Heaters, Inc.



is essential to the anaerobic digestion

process.

Anaerobic digestion results in the creation

of digestate (treated waste) and biogas.

The digestate can be separated into solid

and liquid components, which are rich in

nutrients and can be composted, used as

fertilizer or converted into other products

such as dairy bedding or other fiber-based

products.

Meanwhile, separated biogas can be used

to extract methane, which is the primary

component of natural gas. The methane can

generate electricity or heat, or be recycled

back into the anaerobic digestion system.

Alternately, it is possible to collect and pro-

cess methane into renewable natural gas

and fuel, which can be used locally or sold

to energy providers.

IMPORTANCE OF TEMPERATURE STABILITYTemperature stability of the wastewater

in the anaerobic digester is among the

crucial parameters for effective digestion

and biogas production. Conventional heat

ANAEROBIC DIGESTER SYSTEMFigure 1. This anaerobic digester system block diagram shows how organic waste materials are broken down into digestate and biogas and put back into the environment. Source: EPA



exchangers use a series of hot plates or

tubes that contain heating elements or

hot water. The waste material is heated in

an indirect manner by passing or flowing

across the conventional heat exchanger

elements.

Because it is difficult to control the flow

rate of high-viscosity fluids such as

sludge, this process may result in uneven

heating, which may compromise waste

treatment or biogas production. System

clogging may occur, causing burning

or scorching of the waste material and

requiring costly downtime for cleaning

and maintenance.

Direct steam injection (DSI) has

been used for years in industrial

chemical and pharmaceutical

processing applications such as

biowaste kill and sterilization, which

require uniform processing tempera-

tures. A DSI system can maintain

temperatures rapidly and accurately

for processing difficult materi-

als such as wastewater, thereby

increase the anaerobic digestion

system’s efficiency and reliability.

An example of DSI heater is shown

in Figure 2. The untreated and

unheated liquid slurry enters from

the side of the heater, and the

injection tube injects steam into the slurry

through hundreds of small orifices. Key

aspects of this DSI system design include a

spring-loaded piston that maintains a posi-

tive pressure differential between the steam

and liquid, preventing steam hammer, and

helical flights within the chamber that pro-

mote mixing of the steam with the slurry.

These features heat the slurry instan-

taneously and evenly with an open

flow-through nonclogging design while

providing accurate temperature control.

PHIL HIPOL is a writer for Pick Heaters, Inc. E-mail him

at [email protected].

DIRECT STEAM INJECTION HEATERFigure 2. This heater’s nonclogging design maintains temperatures stability, even for difficult-to-process materials. Source: Pick Heaters




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Tested Technologies for Wastewater Treatment