Poster: The Mor-sand Filter

The Mor-sand Filter Joachim Ibeziako Ezeji, CEO, Rural Africa Water Development Project Kelly Miller, Environmental Engineering, University at Buffalo

Context

Results

The Morsand filter blends the coagulation and flocculation properties of powdered Moringa Oleifera seed with the slow sand filtration process pioneered by the Biosand filter. Moringa oleifera is the best known of the 13 species belonging to the genus Moringaceae. It is a fast growing, drought-resistant tree that is native to subHimalayan tracts of Northern India, but is now distributed worldwide in the tropics and sub-tropics. The press cake obtained as a byproduct of extracting oil from Moringa seeds contains a high level of proteins, approximately 1% of which are active cationic polyelectrolytes that neutralize negatively charged colloids in dirty water. This protein can therefore be used as a non-toxic natural polypeptide for sedimenting mineral particles and organics in the purification of drinking water; industrial coagulants such as alumina can be expensive and toxic, requiring for their proper use qualified personnel which are not readily found in the majority of developing countries. The filter can produce about 100litres of pathogen free water (ie water of less than 100 bacteria/coliforms per 100ml) per day for drinking and cooking use sufficient for 20 persons for up to 18-24 months without any maintenance or operational cost. The components of the filter are made from local materials, with the use of the Moringa Oleifera plant reducing the need for scarce, and often costly, proprietary chemicals. Installed for point-of-use applications, the filter is an innovation in affordable domestic water treatment.

Table 3: Physical Analysis of 100ml of Water Sourced from the Unlined Well Before and After Treatment with the Mor-sand Filter

Physical component

Raw water

After treatment

Temperature (0oC)

30

15

Turbidity (Clarity)

10-15

<10

9.6

7.4

pH

How it works: The Mor-sand Filter is an improvement on using Moringa directly in household water treatment •Mor-sand filter does not entertain any decantation or sieving process •Re-growth of pathogens are never experienced The Mor-sand Filter is also an improved adaptation of the Bio-sand filter •It replaces the Bio-layer existing in the Bio-sand filter with a Moringa paste layer •Coagulates and inactivates pathogens (bacteria, virus, protozoa etc) •Eliminates micro-elements like arsenic, iron, hydro-carbons etc. •Has a strong neutralizing effect on acidic water •Water can be consumed right away •Minimum 17days spent waiting for the Bio-sand’s bio-layer to form The Bio-sand filter is a customized water pollutant attenuation/mitigation mechanism •It adopts the processes of: PREDATION: •where microbes are grown on the top of the topmost sand grains to form the Bio-layer, these microbes (pathogens) subsequently feed on each other, resulting in their elimination. ABSORPTION: •where pathogens escaping from the bio-layer get into the sand but become firmly attached to the sand grains and can not get further. FILTRATION: •where mechanical filtration along the sand beds retard the eventual safe passage of the pathogens.

Performance Evaluation:

In the Mor-sand filter, inter-bed boundaries are the major attenuation points. In addition to coagulation, inter and intra-mechanical filtration within the subsisting beds supported by the absorption process makes the Mor-sand filter an efficient filter for domestic point of use water supply.

Methods

Water Yield:

The protocols used for this evaluation varied. Both the Palintest protocol and Hach Ez Kit were employed in the chemical tests while the membrane filtration principle was employed in the microbial tests.

The Mor-sand filter yields an average of 100litres/day of safe drinking water.Its ability for this performance is the extra finesse and expertise adopted in the sorting of the filtration grains (beds),such that the specific retention rate of water on the grains of each bed is drastically reduced. Specific retention rates observed indicates: Gravel =25% Coarse sand =20% Fine sand =25% The result therefore is an increase in the effective porosity/specific yield of the Mor-sand filter. In making the Mor-sand filter, we attached great importance on the training of filter technicians because of the level of scrutiny we place on the sorting of grains and its proper installation in the filter.

Protocols for Palintest Photometer: Principle of PALINTEST photometer: The photometer is used to measure the colour produced in the water sample when specific reagent tablets are added to test a particular chemical parameter. The photometer measures the percentage of transmission of light through a 10 ml sample tube for a specific wavelength after reaction with one or several reagent tablets. The reference for 100% transmittance is given by a blank tube of water sample without any reagent added. The transmittance reading of the sample tube gives an indication of the concentration of the chemical parameter. For each parameter, a calibration chart provides the concentration corresponding to the transmittance reading.

Implementation Percentage of transmission for the parameter = (I2 / I1) x 100

Photometer 7000

Protocols for Hach Ez Kit: Principle of HACH EZ Arsenic test kit: Arsenic present in a 50 ml water sample is converted into gas by the reagents added (Zinc and Sulphamic acid). The Arsenic accumulates in the headspace above the solution and turns the colour of the reaction zone of a test strip that is set at the top of the Erlenmeyer. Arsenic is trapped further above by another strip set to prevent gas from escaping.

Mass Construction

Demonstrations

Installation

In Uboma, Nigeria, a pilot project has been underway since 2002 in which 183 Mor-sand filters have been installed outside of homes. RAWDP’s long term commitment and target is to formally transit from the Uboma pilot project to an up- scaled adoption of one million filters,which will see a sustained adoption and use in every rural household in the entire state. These 1 million households basically include critical areas with similar water scarcity problems, but the scaling up of the Mor-sand filter is possible anywhere. Table 4: Microbial Analysis of 100ml of Raw Water Pre- Treatment and Post- Treatment:

Membrane Filtration Procedures

*Indicator Organism

Number of colony forming units (cfu) in original water sample.

Number of colony forming units (cfu) observed after 24hours in water sample treated with Moringa powder.

Number of colony forming units (cfu) observed after 24hours in water sample filtered with Bio-Sand Filter.

Number of colony forming units observed 24 hours after treatment with Mor-Sand Filter.

Thermo-tolerant Coliform (E.coli)

Too numerous to count (TNTC)

10

5

0

Faecal Coliform.

145

0

4

0

Table 1: Thermotolerant coliform membrane specifications. MEMBRANE FILTRATION

Currently, the expanding Mor-sand filter networks in Uboma and the entire old Okigwe province including Ihitte, Obowo, Mbaise, Umuahia, Mbano, Owerri,Orlu and Okigwe speak volumes.The expansion of this network is introducing these filter in many more communities and households enable local people to optimize water extracted many sources.

Membrane type(blue) Feeding mediumMembrane Lauryl Sulphate Broth (MLSB) Red liquid stored in sterile bottle – pour 2 ml (using a sterile syringe) on a sterile pad set in the Petri dish Incubation4 hours at room temperature (resuscitation), then 14 hours at 44.5°C IdentificationYellow colonies CONFIRMATION Confirmation-Prepare an universal bottle containing sterile Brilliant Green Broth Media protocol(BGBM) and an inverted Durham tube (label it) -Prepare an universal bottle containing sterile Tryptone Water (TW) -Open the positive plate containing incubated bacteria -Using a sterile microbiological loop, remove a part of a colony and insert it into the BGBM bottle (flame the neck when opening it) -Using another sterile microbiological loop, remove another part of the same colony and insert it the TW bottle (flame the neck when opening it) -Incubate the 2 bottles for 24 hours at 44.5°C -Positive reaction for BGBM if a bubble gas is visible in the inverted Durham tube (production of gas by faecal bacteria) => faecal origin confirmed -Positive reaction for TW if a red colouration is produced in top organic layer of the medium when adding 6-7 drops of Kovacs reagent into the bottle => E.Coli confirmed (if BGBM test is positive)

The total of all costs involved in the project so far is USD 35,000. *Please note that the acceptable drinking water range for these indicators often ranges from 0-10cfu. However the use of these indicator organisms ( WHO, 2003) is limited because they are not reliable for protozoan pathogens. Water quality degeneration was not observed to occur with the Mor-Sand Filter.

MEMBRANE FILTRATION Membrane type(white) Feeding mediumSlanetz and Bartley agar (SB) SB forming a solidified layer at the base of the plate (no need for pad) Incubation48 hours at 44.5°C IdentificationRed colonies CONFIRMATION Confirmation-Prepare a plate containing a solidified layer of Kanamycin Esculin Azide agar protocol(inhibiting medium for bacteria except for Faecal Streptococci) -Open the positive plate containing incubated bacteria -Using a sterile forceps, transfer the membrane to the Kanamycin plate -Incubate for 2 hours at 44°C -Positive reaction for red colonies that have turned olive green/black => faecal origin confirmed

The unit cost of a filter is approximately USD35.00. RAWDP used part of a grant of USD 40,000 donated by African Development Bank (AFDB) in September 2004 to facilitate the project. The Uboma Women Association also enriched the project purse by mobilizing resources through innovative fundraising strategies like “Bob-ajob”. Aside providing free labour, the women also motivated the men to actively provide quality labour and time. RAWDP saved money by volunteering freely its expertise and trained community selected trainees. These trainees all had scholarships. None of the participating NGOs earned an income or wage for her participation. Above all, all the materials (over 95%) used in the project was locally sourced.

Table 5: Chemical Analysis of 100mgl-1 of raw water pre- and post treatment (mgl-1 ): Chemical component

Table 2:Faecal Streptococci.

Funding

Raw water

Treated water

Sulphate

>300

20

Fluoride

>10

1.8

Iron

5.0

0

Negligible

Negligible

Manganese

10

<10

Arsenic

5

0.10

10,000

< 10

Nitrates

15

0

Sodium

200

<1.0

Potassium

10

5.6

Calcium

100

42.8

Magnesium

45

10

Carbonate

20

10

Ammonia

Not established

Not established

Chlorine

5

5

Chloride

Total dissolved solids

Apart from the costs of the metallic molds which RAWDP paid in full because RAWDP contracted a welder who fabricated it, every other item on the project budget was internally handled.

References

WHO, 2004, Guidelines for Drinking water Quality http://www.who.int/water_sanitation_health/dwq/gdwq3/en/ http://www.cawst.org/technology/water treatment/filtration-biosand.php. http://biosandfilter.org/biosandfilter/ Brassington, R.(1998)Field Hydrogeology.Wiley:Chichester,Uk http://www.lboro.ac.uk/well/resources/technical-briefs/60-water-clarification-using-moringa-oleifera-seeds.pdf   http://www.treesforlife.org/project/moringa/uses/uses_water_lgscale_abstract.en.asp   http://info.lut.ac.uk/departments/cv/wedc/garnet/wares.html.