Development & Evaluation of Moringa-Enhanced Biosand Filtration For Use in Nomba, Mozambique

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1 Development & Evaluation of Moringa-Enhanced Biosand Filtration For Use in Nomba, Mozambique Martin Page, SPOUT Institute Kyle Holton, Malo Ga Kujilana WEF Disinfection

2 Thinking out of the box/lab Background Fieldwork Research Future work WEF Disinfection

3 Niassa, the forgotten province MAPUTO Moz. : 21M Niassa : 1M Avg. life exp: 37 years Adult HIV rate: 16% 20% of children die before age 5 WEF Disinfection

4 Malo Ga Kujilana Kujilana.org Farming hope in an impossible environment 5+ yrs in community Holistic approach Anthropology, natural medicine, sustainable agriculture Moringa oleifera WEF Disinfection

5 SPOUT site visit October 2009 Objectives Learn Build trust Survey resources Survey water sources Test options Share findings & listen WEF Disinfection

6 People working incredibly hard just to survive Aware of water causing sickness Not aware of water treatment options Broad range of water sources Key lessons learned Holistic water solution needed that is affordable, requires little effort, and is effective in a variety of water types 6

7 Local Resources Household income <$1 up to $8 (USD), average unknown Local market Clothing, buckets, local goods, some chemicals, Certeza Trades Farming, low-tech pottery, woodcarving, milling Natural resources Clay, sand, gravel, Moringa WEF Disinfection

8 Water quality surveys Previous studies in Niassa Microbial contamination a problem Nitrate also a problem in some wells Rainy season = Diarrhea season SPOUT: Assessed four representative water sources 3 samples each, over 3 weeks Disinfection perspective End of dry season WEF Disinfection

9 Water quality analysis toolkit LTB-MUG Test Phase-change incubator MPN of total coliforms, E. coli Colorimetric Tests (Hach) Nitrate, Ammonia, Iron, Chlorine Test strips (Hach) Titration kits (Hach) Alkalinity, hardness Probes ph, conductivity, temperature WEF Disinfection

10 Water quality results E. coli detected, cfu/100 ml Despite dry season, in two of four wells Isolated nitrate contamination 65 mg/l as N in one well Poor well construction, urban setting General parameters Baseline groundwater ph 6, soft, turbidity < 2 NTU, low conductivity, low chlorine demand Springs and poorly constructed wells Variable levels of ph ( ), turbidity (2-25 NTU), alkalinity ( mg/l CaCO 3 ), hardness ( mg/l as CaCO 3 ), low chlorine demand WEF Disinfection

11 Testing candidate POU technologies Menu approach SODIS Chlorine Biosand filtration Moringa + biosand Pathogen surrogates E. coli MS2 phage WEF Disinfection

12 Waterborne disease intro Microorganisms Sharing and listening POU tech demos SODIS Chlorination Biosand filtration Moringa biosand filtration Community feedback Moringa!! WEF Disinfection

13 SMART empowerment approach S M A R T Simple Microenterprise opportunity Affordable Reliable Transferable Provide >20L/day with minimal effort, time, and complexity Microenterprise creation, local skills and materials Target market- households living on less than $4/day Consistent engineering performance Culturally appealing, low program capital, scalable

14 SMART evaluation of proven POU tech options for Nomba, MZ Tech S M A R T Total Ceramic filter Biosand filter Bleach SoDis PUR sachets Parameters not included: Environmental sustainability; health impact Notes: Positive health impact reported for all five technologies. All values should be considered as opinion only.

15 Challenge testing of POU options Virus removal MS2 phage spike Plaque assay Bacteria removal E. coli spike LTB-MUG most probable number assay

16 Challenge testing results Method MS2 phage removal E. Coli Removal Bleach (HOCl) 2 mg/l, 30 min SODIS 8 hrs direct sun Moringa Biosand (ripened for 8 days) >99.999% >99.99% % >99.99% % 99.3%

17 Advantages Moringa-biosand system Affordable, effective Simple, fast Familiar materials!! Microenterprise potential Disadvantages Still in development/ testing Moringa adds organic matter Moringa difficult to apply at POU

18 SPOUT Research Moringa-biosand system Filter construction with local materials Long term performance evaluations Moringa coagulant optimization Developing a simple coagulant extraction process

19 Concept History: The Green Machine Major findings: Pre-mixing time of just a few minutes resulted in 99.95% virus removal over a 35 day test period. And good biosand performance in a cheap bucket system! Problems: Complexity of coagulant addition step; product water instability; lots of glue used in filter construction.

20 Moringa-biosand theory Depth filtration mechanism for virus removal (not straining) Moringa enhances collision efficiency factor Enhanced interception of viruses on surface of sand grains Result: Better removal with shorter sand column Biological regeneration Viruses retained within the biologically-active filter matrix degrade Elliot et al., 2008

21 Building a prototype bucket moringa biosand filter system in Nomba

22 Building a bucket biosand filter in Niassa Ingredients Bucket Fine sand Fine gravel Old plastic bottle African duct tape Old PETE bag PVC pipe & fittings Target price 100 metacais ~$4 USD

23 Moringa biosand evaluation Virus Concentration (pfu/ml) 1.00E E E E E E E Influent Biosand Filter Effluent Moringa Biosand Effluent Average virus removal of 99.5% over 2 months with Moringa biosand system Time (days) Synthetic Surface Water; 10 5 pfu/ml MS2 loading; Column tests (10 sand, D mm); Moringa pretreatment (50 mg/l, crushed, dissolved, filtered, mixed 1 min) WEF Disinfection

24 Moringa coagulant extraction process Pulverize seeds 2. Dissolve and mix with ion exchange zeolite (clinoptilolite) 3. Pour off supernatant and displace coagulant with salt water (reuse IX resin) 4. Dry in sunlight to get moringa salt 4 3

25 Field trial: Moringa coagulant extraction 20 minutes settling 120 minutes settling Dose 0 mg/l control 3000 mg/l seed 1000 mg/l extract 2000 mg/l extract 3000 mg/l extract 4000 mg/l extract

26 Coagulant extraction efficiency Turbidity (NTU) ~73% recovery of coagulant activity during extraction process. Pulverized Moringa Moringa Extract Coagulant Dose (mg/l of moringa seed) Synthetic surface water; 305 NTU kaolin clay loading; 1 min rapid mix; 10 min slow mix; 2 hr settling WEF Disinfection

27 Conclusions & Future Work POU Moringa biosand filtration has strong potential for applications in Nomba, MZ and many other regions Starting collaboration with ARN-Haiti Remaining research questions Moringa-biosand performance over one year Filter column size requirement Filter housing from recycled HDPE Integrate Moringa coagulant extraction with other Moringa applications WEF Disinfection