1. SIMPLE AND LOW-COST WATER PURIFICATION METHOD USING NATURAL COAGULANT AND DISINFECTANT FOLLOWED BY BIOSAND FILTRATION Sharmin Zaman1,2, Anowara Begum2 and Latiful Bari1 1Center for advanced Research in Sciences, 2Department of Microbiology, University of Dhaka, Bangladesh Presenting and Corresponding authors
Abstract:
Simple and low-cost water purification method was developed using natural coagulant (moringa seed powder) and antibacterial agents (marine shell powder) followed by biosand filtration. In this study, surface water from different sources (e.g. pond, canal, lake and river) were treated with combined moringa seed powder, and shell powder (MOSP) at a ratio 2:1 for 10 minutes showed clear water layer at top and a sediment layer at bottom. The clear water was then passed through an 8- fold sari cloths or natural bio-sand filtration and resulting water was found drinkable. The microbiological and physico-chemical quality of this water showed non-significant differences compared to the USEPA drinking water quality parameters. Moreover, no cytotoxicity of MOSP with BHK-21 and HeLa cells was observed suggested use of MOSP doesn’t pose any adverse health effect. In addition, no bacterial endotoxins were detected in the filtered water. Furthermore, the shelf life of the produced water can be stored at room temperature up to 6 months without compromising the quality, indicating usefulness of this technology in drinking water scarcity areas of the world, because the ingredients used are readily available, inexpensive, user friendly and natural. On the other hand, the sediment or sludge produced in this process could be used in agriculture field after proper compost. Despite similar water purification systems available commercially, this new method would be the simplest, inexpensive and environmental friendly. This simple and easy treatment is particularly helpful for flood prone areas, where there is a scary of drinking water during flood.
Key words: Surface water, moringa seed powder, scallop powder, low cost, water purification.
Comparison of physico-chemical characteristics of raw water and MOSP tread water followed by various filtrations with standard value
Methods:
Moringa Seed Powder
Scallop Shell Powder
Mixing with stirring
Ready to drink
Clear Water
Bio-sand Filtration
Physico-chemical
Parameter
Mean Value of control samples
Mean value of treated samples
EPA
Guidelines Limits for drinking water
BDS Standard
Color
15-19
12-14 (color unit)
15 (color unit)
5(Haxen unit)
Odor
Odorous
Odorless
3 threshold odor number
Unobjectionable
Taste
Not agreeable
Agreeable pH
Salinity (ppt)
0.1
Turbidity
NTU
NTU
NTU
5 NTU
TDS
mg/l
232mg/l
500mg/L
Conductivity µs/cm NS
BOD
mg/l
mg/l
5mg/L
COD
mg/l
mg/l
40mg/L
Iron (mg/L)
0.00
0.3
0.30
Manganese (mg/L)
0.38
0.05
0.50
Lead (mg/L)
0.015
0.01
Zinc (mg/L)
5.00
3.00
Arsenic (mg/L)
Cadmium (mg/L)
0.005
0.003
Results:
SEM
Cytotoxicity test
Figure: Bacteriological quality of raw and treated (pond, river and lake) water stored for 6 months at ambient temperature
Figure: Bacterial (spiked) quality of 6 months stored treated (pond, river and lake) water at ambient temperature
Figure: Comparison of bacteriological quality of raw water (pond, river and lake) and MOSP treated water followed by bio-sand filtration
Figure: Cytotoxicity test of moringa seed powder and scallop powder on BHK-21 and HeLa cell
Figure: Comparison of scanning electron micrographs of a 4 layer and 8-layer of new and old cotton sari
Introduction:
Safe drinking water is a fundamental need for healthy human life and water has been shown to be linked to the development of all areas. Ground water supply of vigorously contaminated due to environmental or anthropogenic reasons not only in Bangladesh but also in many developing countries. Numerous water purification methods were developed to disinfect surface water to make clean water. However, recent studies claim that these methods are becoming un-ecological, expensive to run, manage and maintain, and most importantly, unhealthy. To circumvent the use of chemical agents to purify water, scientists have started focusing on natural products which can be used to treat water. Moringa was found to be a useful plant and many study results showed the coagulation activity of moringa seed powder. On the other hand, many of our previous research showed that heated marine shell powder treatment successfully reduced/ eliminate foodborne pathogens in various food and vegetables. Thus, this study was designed to see the effectiveness of the combination of moringa seed powder and shell powder to inactivate bacteria and coagulate the sediments at the bottom. Then the clear water from the upper portion were pass through bio-sand filter to get the drinking water. Since all the ingredients used are natural thus environment friendly, cheap and available worldwide.
Endotoxin test (LAL test)
Figure: (a) represents the positive control (E. coli O111:B4) ; (b) represents the negative result of test sample
Field Application during Flood
Conclusion:
The bacteriological, physico-chemical quality characteristics results along with the endotoxin and cytotoxicity test results demonstrated the usefulness of this technology in producing drinkable water. This the simplest methods and could be sustainable since the ingredients used are readily available, inexpensive, user friendly, natural and eco-friendly. Just need to trained the people of this technology so that they can use this science to get safe water in any emergency situation.
Molecular technique:
Objectives:
To develop a simple, low-cost and environmental friendly technology using locally available materials to convert surface water to drinkable water.
To develop science based confirmation of this simple technology using cultural, immunological, molecular and. microbiological methods.
To evaluate the effectiveness of this technology in the field.
Selected References:
Ali, E. A., Muyibi, S. A., Salleh, H. M., Salleh, M. R. M., & Alam, M. Z. (2009). Moringa oleifera Seeds as Natural Coagulant for Water Treatment. Thirteenth International Water Technology Conference, Hurghada, Egypt,
Sawai, J., Nagasawa, K., and Kikuchi, M. (2013). Ability of Heated Scallop-Shell Powder to Disinfect Staphylococcus aureus Biofilm. Food Science and Technology Research, 19(4),
Figure: Representative E. coli was confirmed by detecting specific uidA gene using molecular method