Clean Drinking Water: Solving Arsenic Crisis through a Sustainable Local Filtration Technology

Transcription

1 Clean Drinking Water: Solving Arsenic Crisis through a Sustainable Local Filtration Technology Abul Hussam Department of Chemistry & Biochemistry George Mason University Fairfax, Virginia USA =FeOH + H AsO =FeHAsO H 2 O (K = ) =FeOH + HAsO 2-4 =FeAsO H 2 O (K = ). Roundtable on EHSRM, Inst of Medicine of National Academies, Oct 17,

2 PEOPLE INVOLVED Abul K. M. Munir MSUK, Kushtia, Bangladesh Amir H. Khan Department of Chemistry, University of Dhaka, Dhaka, Bangladesh Abul Barkat Department of Economics, University of Dhaka, Dhaka, Bangladesh MSUK-SDCI Kushtia Laboratory Dr. Tahmina Begum, Abu Sayeed, Monwar Ahmed, Mir Morshedur Rahman, Mizanur Rahman, Ziaul Haq, and many others. 2

3 OVERVIEW Occurrence: Where? Arsenic Mitigation through Filtration 3

4 Tube-wells in Bangladesh 4000 ppb As (Total) Bheramara, Kushtia 170 ppb As(Total) Sadar Kushtia Arsenic free well Sadar, Kushtia 4

5 WATER FREE FROM TOXIC SPECIES 5

6 Arsenic: Toxicity and Health Effects Toxic Levels of Arsenic in Water WHO Guideline: 10 µg/l (ppb) Bangladesh Limit: 50 µg/l USEPA : 10 µg/l Dermatological Symptoms Diffuse melanosis Spotted melanosis Leucomelanosis Mucus membrane melanosis Spotted keratosis Cancer Human liver degenerates at 800 ppb Santra A, Das Gupta J, De BK, Roy B, Guha Majumder DN. Hepatic Manifestation in Chronic Heavy Metal Toxicity. Inidan J Gasroenterology. 1999, 18,

7 Bangladesh: Arsenic Scenario Population: 140 million Area: 46,560 sq. miles Tubewells: 10 million (1940, UNICEF 1970) Origin of arsenic: Groundwater (<200 m depth) Cause: Bio-geochemical reduction process Contaminated wells: 27-50% People affected: million Arsenical skin lesions: 1.2 mil Children at risk: 35 million Cancer risk: 1-3 per 1000 people A CRITICAL PUBLIC HEALTH CRISIS! (Map: Rahman et. al. ES&T. 2002, 36, )

8 Summary of Contamination Data Chakraborti and Zaman, July 2006 Report Shallow Tubewells: in 64 Districts 40.3 % with above 10 ug/l As 26.6% with above 50 ug/l Deep Tubewells: 261 wells 49.8% with above 10 ug/l 15.6% above 50 ug/l % of TWs exceeding 50 μg/l limit Y = X R 2 = 0.29 p = k = 30 age groups Total N = Age of the Tubewells (Year)

9 THE SOLUTION DRINK WATER FREE FROM TOXIC SPECIES 9

10 TOXICITY OF ARSENIC COMPOUNDS IN DECREASING ORDER R 3 As ( R = H, -CH 3, -Cl) As(III) (H 3 AsO 3 ) (RAsO) n As(V) (H 2 AsO 4-, HAsO 2-4 ) R n AsO(OH) 2-n (n= 1,2) R 4 As+ As o arsines arsenites arsenates organo-acids arsonium elemental arsenic Source: Reimer and Cullen, Chemical Review 10

11 ARSENIC MITIGATION THROUGH FILTRATION Zero Valent Iron (Fe o ) To Composite Iron Matrix (CIM) 11

12 Simple and Effective Arsenic Filter Based on Fe o (1999) 3-KOLSHI FILTER 3-Pitcher Filter 12

13 Environmental Technology Verification for Arsenic Mitigation (ETVAM) Reports ETVAM 1 Rapid Assessment of Household Level Arsenic Removal Technologies RAPID Phase I - Final Draft Report, Bangladesh Arsenic Mitigation Water Supply Project (BAMWSP) / DFID / Water Aid, January 2001 (ICP Analysis) ETVAM 2 Performance Evaluation and Verification of Five Arsenic Removal Technologies: ETVAM Field Testing and Technology Verification Program. Bangladesh Council of Scientific and Industrial Research (BCSIR), Dhaka, Bangladesh. September

14 RAPID ASSESSMENT: BAMWSP/DFID/WATER AID Phase II Report, March 2001, WS Atkins Sono 3-K CIM BDL ppb ; 34 L/day; Tk 300 T Ion Exchange, USA ppb; 201 L/day; Tk

15 Arsenic Filter Based on Composite Iron Matrix Flow: Liters per hour As(Total) < 10 ppb (CL 95%) As(III) < 2 ppb (CL 99.9%) Life: 5 Years Minimum Maintenance: Very low Cost: US $ $40.00 Waste: Completely nontoxic Government approved and ETVAM program verified SONO FILTER 15

16 SONO Filter Based on CIM SONO FILTER 16

17 Filter Production & Distribution Measurement of effluent total arsenic less than 20 ppb is critical to filter quality control 17

18 Filter Distribution 18

19 SONO: Field Test with Groundwater As(Total), ug/l As(Total), ug/l y = x R 2 = Water Yield, L Water Yield, L Blue: As in Tubewell water, Pink: Filtered water. Right graph shows progressive decrease in arsenic. Initial [Fe] total = 6.46 mg/l (#4) 19

20 Performance of Blank Filters As(III) or As(Tot), ug/l As(III), Sand Filter As(Tot), Sand Filter As(III), Brick+Sand+Charcoal As(Tot), Brick+Sand+Charcoal Total volume, L Figure shows blank filters maximum contaminant limit (MCL) breakthrough occurs the first day even at 88 L. Groundwater composition: As(III): 300 ug/l, As(total) 996 ug/l, and Fe(II) 1.0 mg/l. The filtered water properties: Sand: Temperature 27.3 C, ph 7.6 ± 0.1, TDS 210 ± 6 (us/cm), E h 158 ± 6 mv vs. NHE. Sand+Brick+Charcoal: Temperature 25.7 C, ph 7.9 ± 0.1, TDS 208 ± 12 (us/cm), E h 148 ± 6 mv vs. NHE. Filtered water has no detectable total Fe (III + II). 20

21 Authors Home Court Para, Kushtia Village Home Khordosadhua, Koksha, Kushtia Years in use: Total water filter (L): 125,000 L 100,000 As(T) influent (ppb): 155 ±7 600 ± 6 As(T) filtered (ppb): 7 ± 1 8 ± 1 Fe(T) influent (ppm): 4.85 ± ± Fe(T) filtered (ppm): ± ± 0.05 Cost (Taka)/L: N

22 SONO Filter Performance in the Field Parameters Fatic Alampur Kaliskhnpur Juniadah Years Water Yield (L) 67, , ,480 72,960 Number of Measurements As(Total)- Input, ppb 32 ± ± ± ± 87 As(Total), Filter, ppb <2 8 ± 2 7 ± 2 8 ± 4 Fe(Total) Input, ppm 20.7± ± ± ± 0.03 Fe(Total) Filter, ppm 0.22 ± ± ± ± 0.03 Cost, Taka/L

23 One Year Summary of Filter Performance in Hazigong, Comilla 165 SONO Filters, 300 Arsenicosis Patients + Household (3000 people) Tubewell water: ppb ( > 50% As(III)) Filtered water: <2 ppb (70%), <10 ppb (20%), <30 ppb (10%) (n= 145) No change in flow rate, no maintenance for 12 months Later, 400 more SONO filters were installed Ref: DOUBLE-BLIND, RANDOMIZED, PLACEBO-CONTROLLED TRIAL OF ANTIOXIDANT VITAMINS AND MINERALS IN THE TREATMENT OF CHRONIC ARSENIC POISONING IN BANGLADESH, Final Report 2003, G. H. Rabbani et. al., Bangladesh Arsenic Control Society Research Group. Sponsored by UNICEF and Government of 23

24 Evaluation of Grainger Challenge Arsenic Treatment System Species Influent (mg/l) ± SD Effluent (mg/l) ± SD As (Total) ± ± As(III) ± ± As(V) ± ± Iron ± ± Calcium ± ± 4.37 Aluminum ± ± Magnesium ± ± Sodium ± ± 1.49 Silicon ± Sulfate ± ± Chloride ± ± Nitrate ± ± Phosphate ± ± Water Quality: EXCELLENT 24 TCLP of used CIM: Non detectable and non hazardous (Limit 0.50 mg/l)

25 Reactions with Composite Iron Matrix (CIM) CIM surface and soluble iron Fe(II) + O 2 O2.- + Fe(III)OH2+; log k = ph Fe(II) + O H+ Fe(III) + H 2 O 2 ; k = 10 7 Fe(II) + CO3.(2-) Fe(III) + HCO3- H 2 O 2 + H 3 AsO 3 H 2 AsO 4- + H 2 O + H + CIM and hydrous ferric oxide, HFO. =FeOH + Fe(III) + 3 H 2 O Fe(OH) 3 (s, HFO) + =FeOH + 3H+ ( =FeOH is the surface of hydrated iron ) CIM and surface complexation =FeOH + H 2 AsO 4 - =FeHAsO 4- + H 2 O (K = ) =FeOH + HAsO 4 2- =FeAsO H 2 O (K = ). 25

26 Drinking water inorganic quality parameters: Comparison of 3-Kolshi and Sono bucket filter with international and national standards. Results include independent test results by WS Atkins. 3-Kolshi was approved by the Bangladesh Arsenic Mitigation Water Supply Project, BG for household use. Constituent USEPA (MCL) WHO, Guideline Bangladesh 3-Kolshi Water b Sono Bucket Filter Water b Arsenic (total) mg/l Iron (total) - mg/l (1.0) ± 0.02 ph ± ± 0.1 Sodium - mg/l ± Calcium - mg/l 75 (200) 59.1 ± Copper - mg/l <0.002 Manganese - mg/l (0.5) <0.001 <0.01 Zinc - mg/l (15) 0.01 <0.007 Aluminum -mg/l (0.2) 0.03 <0.022 Lead -mg/l <0.004 Chromium, mg/l <0.002 <0.002 Cadmium, mg/l <0.001 <0.001 Barium, mg/l ±0.01 <0.082 Antimony, mg/l <0.013 <0.013 Molybdenum, mg/l <0.002 Nickel, mg/l <0.002 <0.002 Selenium, mg/l <0.012 <0.002 Silver, mg/l 0.1 <0.002 <0.002 Chloride, mg/l (600)

27 Bacteriological Test Data Thermo tolerance coliform (ttc/100 ml) SUMMARY Arsenic Mitigation Pilot Project: Bacteriological field test report Dhalipara & Doazipara of Muradpur Union in Sitakunda Duration: April March SONO filters tested at 61 locations, 264 tests 16 test with 2 counts, 248 with 0 count Village Education Resource Center (VERC) B-30, Ekhlas Uddin Khan Road, Anandapur, Savar, Dhaka-1340, Bangladesh. 27

28 Singing Group Performing Songs on Arsenic and Filter Use in a Village Gathering Khordosadhua, Kokhsa, Kushtia. Jan 11, 2004 Kushtia Motivational Singers 28

29 SONO TM Arsenic Filter at Work : 4000 ppb to 7 ppb As 4000 ppb As Jagassar, Bheramara, Bangladesh 7 ppb As after SONO Filtered SONO by SDC/MSUK, Kushtia, Bangladesh 29

30 Managing Spent Material and Waste Disposal Issues 30

31 How much arsenic is on the ground? 5 million working tubewells 100 L/ day with 100 ug/l arsenic 50 kg arsenic /day 18,250 kg arsenic / year At 50% level total arsenic = 91,250 kg / 10 yrs Most of the arsenic is bound to soil Iron bound arsenic has very low bioavailability 31

32 TCLP and SONO Filter TCLP new limit for arsenic = 0.50 mg/l 32

33 CIM DISPOSAL AND RECYCLING 1. CIM is a natural non toxic material 2. CIM can be disposed in the open 3. CIM does not leach arsenic (Grainger-USEPA) 4. CIM can be recycled and reused 5. CIM can be used to make metallic iron SONO IS A GREEN FILTER Toxicity Characteristic Leaching Procedure (TCLP) of used CIM: Non detectable and non hazardous (Limit 0.50 mg/l) 33

34 Victims of Ground Water Arsenic Poisoning in Bangladesh Md. Humayan Kabir at the age of 8 and at the age of 12 years. He is drinking arsenic free water from MSUK s SONO FILTER for 4 years. Now he is safe. Melanosis in Body Keratosis in Palm 34

35 USAGE INFORMATION (2001- May 2007) 42,500 SONO TM filters installed in 18 districts liters per day consumed for 2-5 years >1 Million direct beneficiaries >1 Billion liter of clean water consumed Cost: < Taka / Liter 35

36 Students carrying filtered water home 36

37 SONO Dual Filters 80 L/ hour 2423 to 8 ppb As(T) 37

38 IN WATER PURIFICATION Surface water, groundwater for drinking Rainwater and sea-water Piped water at origin and in-house FILTRATION IS THE KEY 38

39 Organizations Involved Chemistry Department, George Mason University, USA SONO Diagnostic Center EI, Kushtia MSUK: Manob Sakti Unnayan Kendro, Kushtia Die Lichtbruche, Germany HDRC: Human Development Research Center, Dhaka, Bangladesh Quasem-Nahar Trust Fund, Kushtia 39

40 FOR INFORMATION PLEASE CONTACT Abul Hussam Dr. A. K. M. Munir Manob Sakti Unnayan Kendro (MSUK) Courtpara, Kushtia Bangladesh 40