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

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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

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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

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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

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ECAR sludge embedded in concrete

ECAR consistently delivered < 4 ppb As in field

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Project Website:

http://arsenic.lbl.gov

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Supplemental Slides Follow

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> 10 million tubewells installed in Bangladesh alone

Massive switch to tubewells accomplished in

Bangladesh and West Bengal (1970-2000)

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> 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

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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

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