Simple filtration and low-temperature sterilization of drinking water. CURRENT SCIENCE, VOL. 104, NO. 4, 25 FEBRUARY 2013

• Full text, pdf

Nandini Nimbkar, et al

Waterborne infectious diseases are transmitted primarily through contamination of the water sources with excreta of humans and animals. The water treatment technologies available are fairly costly and not sustainable. Solar energy can be used effectively for sterilizing drinking water during clear and partially cloudy days. However, during mostly cloudy days the temperatures required may not be reached. A combination of traditional cotton-sari filtration and heating of water to simulate a solar boiler was evaluated as a water sterilization treatment.

Experimental data showed that filtration of raw water through fourlayered cotton-sari cloth (250 μm) reduced the coliform count and further heating to sub-boiling temperatures (55–60°C) for less than an hour resulted in
complete inactivation of coliforms. The use of cloth filtration and low-temperature solar sterilization can be an effective, feasible and environmentally sustainable technique of disinfection to obtain clean drinking water.

Journal of water, sanitation and hygiene for development, 2011, vol. 1, no2, pp. 112-123

Efficacy of an appropriate point-of-use water treatment intervention for low-income communities in India utilizing Moringa oleifera, sari-cloth filtration and solar UV disinfection

ALI Syed Imran ; MACDONALD Morgan ; JINCY J. ; ARUN SAMPATH K. ; VINOTHINI G. ; PHILIP Ligy ; HALL Kevin ; ARONSON Kristan ;

This study investigated the efficacy of a POU water treatment system featuring sari-cloth filtration and/ or Moringa oleifera coagulation as pre-treatments for solar disinfection (SODIS). Surface water from a peri-urban slum in Chennai, India, was treated and analysed for turbidity, organic content via chemical oxygen demand (COD) and microbiological quality via most probable number (MPN) enumeration of total coliforms. Pre-treatment with both moringa coagulation and sari-cloth filtration significantly improved the turbidity of raw water compared to no pre-treatment controls (P = 0.0002).

Optimal moringa coagulation did not outperform sari-cloth filtration (P = 0.06), but combining optimal moringa coagulation with sari-cloth filtration significantly outperformed either pre-treatment independently with respect to turbidity (P = 0.016 and P = 0.0001, respectively). The addition of moringa was found to increase COD in treated water, with greater doses of moringa resulting in higher COD levels (P = 0.04). Increased organics may have encouraged the re-growth of coliform bacteria that was observed in those jars receiving moringa coagulant such that, with respect to MPN, those jars which were subject to optimal moringa coagulation did not outperform those undergoing sari-cloth filtration alone (P = 0.41).

Sari-cloth filtration is recommended as a pre-treatment for SODIS whereas moringa is not, as further investigation on the relationship between organics and bacterial re-growth is necessary.

Journal of Water, Sanitation and Hygiene for Development Vol 1 No 2 pp 112–123 2011 doi:10.2166/washdev.2011.043

Efficacy of an appropriate point-of-use water treatment intervention for low-income communities in India utilizing Moringa oleifera, sari-cloth filtration and solar UV disinfection

Syed Imran Ali, Morgan MacDonald, J. Jincy, K. Arun Sampath, G. Vinothini, Ligy Philip, Kevin Hall and Kristan Aronson

School of Engineering, University of Guelph, Guelph, Canada E-mail: alis@uoguelph.ca
Department of Civil Engineering, Indian Institute of Technology Madras, Chennai, India
Department of Community Medicine and Epidemiology, Queen’s University, Kingston, Canada

This study investigated the efficacy of a POU water treatment system featuring sari-cloth filtration and/or Moringa oleifera coagulation as pre-treatments for solar disinfection (SODIS). Surface water from a peri-urban slum in Chennai, India, was treated and analysed for turbidity, organic content via chemical oxygen demand (COD) and microbiological quality via most probable number (MPN) enumeration of total coliforms. Pre-treatment with both moringa coagulation and sari-cloth filtration significantly improved the turbidity of raw water compared to no pre-treatment controls (P = 0.0002). Optimal moringa coagulation did not outperform sari-cloth filtration (P = 0.06), but combining optimal moringa coagulation with sari-cloth filtration significantly outperformed either pre-treatment independently with respect to turbidity (P = 0.016 and P = 0.0001, respectively).

The addition of moringa was found to increase COD in treated water, with greater doses of moringa resulting in higher COD levels (P = 0.04). Increased organics may have encouraged the re-growth of coliform bacteria that was observed in those jars receiving moringa coagulant such that, with respect to MPN, those jars which were subject to optimal moringa coagulation did not outperform those undergoing sari-cloth filtration alone (P = 0.41). Sari-cloth filtration is recommended as a pre-treatment for SODIS whereas moringa is not, as further investigation on the relationship between organics and bacterial re-growth is necessary.