Improving household water filter for arsenic removal in Cambodia: localized production and...

8/9/2019 Improving household water filter for arsenic removal in Cambodia: localized production and distribution of granular iron oxide

1/42

International Workshop on Sustainable Water Technology:

Appropriate Technology for Water in Asia (9-13 Feb 2015)

Improving household water filter for arsenic

removal in Cambodia: localized production and

distribution of granular iron oxide

Professor Chih-Hsiang Liao

Dept. of Environ. Resources ManagementChia Nan University of Pharmacy and Science

Tainan, Taiwan

[email protected]; http://chliao.postach.io/
mailto:[email protected]://chliao.postach.io/http://chliao.postach.io/http://chliao.postach.io/http://chliao.postach.io/mailto:[email protected]:[email protected]


2/42

Indochina


3/42

Demographic Data


4/42

Outline

Arsenic painful story in Taiwan

iWatch on Cambodia water

Household water filters

Iron-oxide furnished household water filters

Summary

Acknowledgement


5/42

Arsenic painful story

in Taiwan

A Mukherjee, MK Sengupta, MA Hossain, S Ahamed, B Das, B Nayak, D Lodh, MM Rahman,

and D Chakraborti. Arsenic Contamination in Groundwater: A Global Perspective with

Emphasis on the Asian Scenario. J HEALTH POPUL NUTR 2006 Jun; 24(2):142-163.


6/42

st

aquifer

2

nd

aquifer

3

rd

aquifer

4

th

aquifer

Arsenic conc. dist. in differentlayers of aquifer

Southwest

Coast

Focused Area in Taiwan

http://e-info.o

rg.t

w/column/underwa

ter/2005/gw05081201.h

tm
http://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htmhttp://e-info.org.tw/column/underwater/2005/gw05081201.htm


7/42

Deep well water

Shallow well water

Seawater intrusionin the coastal area

http://www.blackfoot.org.tw/know/know.html
http://www.blackfoot.org.tw/know/know.html


8/42

Incidence of arsenic contamination in

artesian well water

Source material of arsenic: pyritic materialor black shale occurring

in underlying geological strata Well-documented in 1961-1985

The southwest coast of Taiwan

Affected population: 140,000

Arsenic content: 10-1820 g/L (tested); 400-600 g/L (endemic area)

Predominating arsenic species: As(III) (average As(III)/As(V) = 2.6)


9/42

Arsenicosis and related diseases

Incidence as early as 1920; a post-war outbreak in 1956

40,421in 37 villages

7,418(hyper-pigmentation); 2,868(keratosis), and 360(BFD);

Some cases of cancer(liver, lung, skin, prostate, bladder, kidney) in

the endemic areas.

Diseases, such as cancer, diabetes mellitus, cardiovascularanomalies, hypertension, and cerebral apoplexy, occurred at

significantly higher levels than in the areas free of blackfoot disease.


10/42

Blackfoot Disease(BFD)

A peripheral vascular disease: spotted discolorationon the skin of

the extremities, especially the feetthe spots changing from white

to brownand eventually to black(hence the name BFD)the

affected skin thickening (keratosis), cracking and ulcerating(lesion)amputationof the affected extremities to save the victims

Arsenicalone was thought to be responsible. Later on, the

fluorescent humic substances in combination with arsenic are the

probable cause of BFD. In 1975, a total of 1141BFD patients were identified in this area (20

km north of Tainan). [Chen et al. (1994), ES&T]


11/42

Endemic

level

Arsenic

exposureDiagnosis Action

30 > 350 ppb

Occurrence of arsenicosis;

Children with skin symptom of

chronic arsenicosis.

Require remedy

measures since

arsenic hazard has

taken place.

20 ~ 350 ppb

No occurrence of arsenicosis;

A few cases of skin symptom of

chronic arsenicosis, or no skin

symptom but with quite limited

cases of blackfoot disease

Preventive measures

are to be taken,

knowing arsenic

hazard has just

begun.

10 > 350 ppb No occurrence of blackfoot disease

No skin symptom of arsenicosis

Take preventive

measures long before

arsenic may cause

any hazard.

Classification of endemic arsenicosis

Field experiences (1/3)


12/42


13/42

Phase Goal and outcomesI. (1971-1975) Center for blackfoot disease prevention and control

Blackfoot disease prevention team

Tap water pipe installation

New patientsdecreased by 72% when compared to

those 5 years agoII. (1977-1981) Abatement of groundwater intake in endemic area

Tap water supply

Reducing new incidence, especially those with age


14/42

iWatch on Cambodia water


15/42

Arsenic Alert

Arsenic threat found in groundwater survey Fri, 18 August 2000. Phelim Kyne

Arsenic poisoning suspected by testing Fri, 5 January 2001. Phelim Kyne

Arsenicosis

Well-water users show signs of arsenic poisoning Thu, 21 September 2006.Cheang Sokha

Arsenic deaths

Arsenic deaths stalk Kandal village Wed, 4 August 2010. Will Baxter and Sun Narin

Silent killer taking toll (Kandal province)Wed, 19 March 2014. Laignee Barron and SenDavid.

Search Arsenic in the PPP


16/42

Arsenic Affected Provinces

2.25 million people living within the arsenic affected area


17/42

1 Phnom Penh Municipality 14 Oddar Meanchey Province

2 Banteay Meanchey Province 15 Pailin Province (municipality)

3 Battambang Province 16 Preah Sihanouk Province

4 Kampong Cham Province 17 Preah Vihear Province

5 Kampong Chhnang Province 18 Pursat Province

6 Kampong Speu Province 19 Prey Veng Province

7 Kampong Thom Province 20 Ratanakiri Province

8 Kampot Province 21 Siem Reap Province

9 Kandal Province 22 Stung Treng Province

10 Koh Kong Province 23 Svay Rieng Province

11 Kep Province(municipality) 24 Tako Province

12 Krati Province 25 Tbong Khmum Province

13 Mondulkiri Province

Provinces of Cambodia


18/42

Prek Russey/Koh Thum/Kandal

The Most Focused Village


19/42

J. Buschmann, M. Berg, C. Stengel, and M.L. Sampson. Arsenic and Manganese Contamination of Drinking Water Resources in Cambodia:

Coincidence of Risk Areas with Low Relief Topography . Environ. Sci. Technol. 2007, 41, 2146-2152.

Arsenic level within the catchment of

Tonle Sap, Mekong and Bassac Rivers


20/42

Population with suspected Arsenicosis symptoms

Info source: arsenic in Cambodia (Arsenic Center Camobdia)


21/42


22/42

Info source: arsenic in Cambodia (Arsenic Center Camobdia)

Governments Response (2/2)

MRD: Water supply rate in rural area

100% in 2025

70%(50%) in 2015(Note: 31% in 2006)

KAP(Knowledge, Attitude and Practice) survey to asses the

extent of awareness and practice relating to arsenic

5 year arsenic mitigation strategic action plans

Capacity building: both national and provincial teams includingestablishment of arsenic center at MRD

Collaboration with other partners to respond to the problem

Ministry of Rural Development


23/42

Household Water Filters


24/42

Ceramic Water Purifier (CWF)

http://www.rdic.org/water-ceramic-filtration.php

Physical straining of dirt and bacteria out of the water as they are too large

to pass through the ceramic substrate.

Chemical action of colloidal silver as a biocide to kill microbes.

Indirect sedimentation of particles within the pores of the filter.

Clay and laterite (optional) + rice husks;

Firing in the kiln;

Silver nitrate painted onto the inside

and outside surfaces of the filter

46% reduction in diarrheal disease between filter users and non-users

95.1% average (and up to 99.99%) reduction of E.coli in drinking water

90-99% reduction in viruses

A highly successful means of empowering households to manage their own safe water supply.


25/42

Ceramic filter pilot projects (2002-

2006) in Cambodia have yielded

promising results that suggest these

interventions can be effective in

improving drinking water quality and

can contribute to substantial health

gains in populations using them.

Improving Household Drinking Water Quality:

Use of Ceramic Water Filters in Cambodia


26/42

Pipe

Arsenic Biosand Filter (ABF)

KanchanTMArsenic Filter (KAF)

1. Tommy Ngai (MIT) and Sophie Walewijk (SU). THE ARSENIC BIOSAND FILTER (ABF) PROJECT: DESIGN OF AN APPROPRIATE HOUSEHOLD

DRINKING WATER FILTER FOR RURAL NEPAL. Final Report July 2003.

2. B. Ghimire. KANCHANTMARSENIC FILTER: Can Iron and Arsenic Particles Migrate through the Sand Layer? A research project submitted to

Massachusetts Institute of Technology And Environment and Public Health Organization (>2005).

3. TKK Ngai, B Dangol, SE Murcott, RR Shrestha (Eds). A simple solution for arsenic problem: KanchanTMArsenic Filter. April 2005, Environment

and Public Health Organization (ENPHO).

4. S Chea, S Mao, D Uy, TKK Ngai, T. Mahin. Kanchan Arsenic Filter Evaluation of Applicability to Cambodia, Phase I Technical Report,September, 2008.


27/42

ABF/KAF/Rural Nepal

As: 87-96% (mean = 93%)

Total coliform: 0 - >99% (mean = 58%),

E. Coli : 0 - >99% (mean = 64%)

Iron: >90 - >97% (mean = >93%).

The users liked the high flowrate (range = 4-23 L/hr, mean

= 14 L/hr), simple operation, minimal maintenance, as wellas the clean-looking and good-tasting water coming out of

the filters. They think the filter is a durable, permanent

solution to their drinking water problems.

Performance


28/42

Design flow rate (15-20 L/hr)

Amount of iron nails (5 kg)

Maximum allowed influent arsenic (500 ppb) and iron (10 ppm)

Short circuiting due to the incoming water which may dispersenails

Arsenic adsorption capacity for different type of iron nails?

Possible harmful substances leaching from nails?

Using constructing materials available to villagers?

Capability of sand layer for retaining iron and arsenic particles?

Filter cost reduction? (1400-1800 NRs or $20)

Concerned Aspects

ABF/KAF/Rural Nepal


29/42

KAF Evaluation/Rural Cambodia

KAF found highly effective with high arsenic and

phosphate levels of raw water

Arsenic of 637 ppb dropped down to


30/42

Sono 3 Kolshi Filter/Bangladesh

Developed by a team led by Prof. Hussamand Dr. Munir in 2001 using composite

iron matrix (CIM) as the active arsenic

removal component

Clean water production rate: 30 L/hr

$35; life span of >5 year

Test data:

80-1900 ppb (Astotal)10-12 ppb;

73-1170 (As(III))


31/42

Iron-oxide furnished

Household Water Filter


32/42

Iron oxide preparation: Fundamental

Seeding material (e.g., quartz sand)

Ferric oxide, Fe2O3(s)

Ferric hydroxide, Fe(OH)3(S)

Goethite, FeOOH(s)

Fe2+ Fe3+

Oxidizing

Agent:O2, KMnO4, HO

Iron oxide

Air

Fenton


33/42

Feo-based Treatment System for Nitrate Removal

Iron Precipitation by Fluidized Sand Bed Process

I. Production of Iron-coated sand (iron pellets)


34/42

Conditions:Initial influent Fe2+= 300-375 mg/L

Sand dosage = 25 kg (no classification)

Air Flow rate = 5 L/min

Feeding flow rate = 50 mL/min

Retention time = 11.25 hrsSand size distribution:

< 0.297 mm = 0.6%

0.297-0.42 = 2.6%

0.42- 0.59 = 25.4%

0.59-0.84 = 66.6%

> 0.84 mm = 4.8%

I. Production of Iron-coated sand (iron pellets)


35/42

Characteristics of iron-oxide pellets(a) pH variation and (b) total iron release.

0 1 2 3 4 5 6 7 8 90

1

2

3

4

5

6

7

8

(a)

pH

T i m e e l a p s e d , h r s

pH = 5

pH = 6

pH = 7

pH = 8

0 1 2 3 4 5 6 7 8 9

0.0

0.5

1.0

1.5

2.0

2.5

3.0(b)

Totaliro

n

,ppm

T i m e e l a p s e d, h r s

pH = 5

pH = 6

pH = 7

pH = 8

Iron-oxide pellets = 3 g/125 mL; Temp = 25.


36/42

Arsenate adsorption equilibrium test(a) pH variation; (b) arsenate removal.

0 2 4 6 8 10 12 14 16 18 20 22 24 260

1

2

3

4

5

6

7

8

(a)

pH


pH = 5

pH = 6

pH = 7

pH = 8

0 2 4 6 8 10 12 14 16 18 20 22 24 26

0

10

20

30

40

5060

70

80

90

100

110

(b)

Arsenate

Re

moval,%


pH = 5

pH = 6pH = 7

pH = 8

Iron pellets = 3 g/125 mL; initial As (V) = 200 g/L; Temp = 25


37/42

Arsenic removal profiles

0 50 100 150 200 250 300 350 400 450 5000

10

20

3040

50

60

70

80

90

100

ArsenateRemoval,%

As (V) , ppb

As(V) , pH = 5

As(V) , pH = 6

As(V) , pH = 7

As(V) , pH = 8

5.0

5.5

6.0

6.5

7.0

7.5

8.0

pH = 5

pH = 6

pH = 7

pH = 8

(c)

FinalpH

0 50 100 150 200 250 300 350 400 450 5000

10

20

3040

50

60

70

80

90

100

ArseniteR

emoval,%

As (III) , ppb

As(III) , pH = 5

As(III) , pH = 6

As(III) , pH = 7

As(III) , pH = 8

5.0

5.5

6.0

6.5

7.0

7.5

8.0

FinalpH

(c)

pH = 5

pH = 6

pH = 7

pH = 8

Initial arsenic = 150-400 ppb; iron-oxide pellets = 2 g/125 mL


38/42

Iron oxide modifying fluidized bed reactor

(Huang et al., 2011, J. Haz Mater.)

Adsorbent dosage = 2.5 g/500 mL;initial As = 70 ppm;

pH=3

II. Production of KMnO4-modified iron oxide

Arsenic removal performance pH = 3

KMnO4/FeCl2 BT-4 (40 g) as

a support


39/42

Iron crystallization reactor

(Boonrattanakij et al., 2011, Wat. Res.)

III. Production of Fenton-initiated iron oxide

[Fe2+

]= 2 mM; [H2O2]= 20 mM;Coated sand: 230.77 g/L;

pH = 3; 25oC; 50% bed expansion;

1 h crystallization period.

Iron leaching test


40/42

Iron oxide furnished household water filters

Granular iron

Iron production

Iron supplier


41/42

Summary

iWatch on Cambodia water will be followed closely and

continuously.

Iron-oxide furnished household water filters need to be

tested for its arsenic removal performance.

Academic researchers and social entrepreneurs will be

mobilized to involve in the future localized production

of iron oxide, if tested successfully and economically.


42/42

Acknowledgement

Comments of

Professors MC Lu, MW Wan, CC Kan

Chia Nan University of Pharmacy and Science, Taiwan

Professor YH Huang,

National Cheng Kung University, Taiwan

are highly appreciated.

Date post:	02-Jun-2018
Category:	Documents
Upload:	chih-hsiangliao
View:	217 times
Download:	0 times

Improving household water filter for arsenic removal in Cambodia: localized production and...

Documents