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Author: search.filters.author.Pillay, Visvanathan LingamurtiHas files: No

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    Development and evaluation of a small scale water disinfection system
    (IWA Publishing, 2016-07-08) Alfa, Dorcas; Rathilal, Sudesh; Pikwa, Kumnandi; Chollom, Martha Noro; Pillay, Visvanathan Lingamurti
    Provision of microbiologically safe drinking water for people living in the rural areas of developing countries remains a major challenge to date. A simple gravity-driven membrane point of use system was developed based on woven fabric microfiltration (WFMF) membranes. The WFMF is a loose type of membrane (0.45 μm). However, complete disinfection is not achieved with the WFMF, hence it was incorporated with two disinfectants. This study aimed to combine the WFMF with two disinfectants (Water guard and bromochlor tablets) to bring the water to the accepted quality for drinking. Four different types of water were sourced, considering two factors; E. coli and turbidity content. The WFMF demonstrated excellent filtration performance by producing permeates with turbidity less than 1 NTU for feed turbidity ranging between 10 and 200 NTU. There was 95–99.8% E. coli removal for raw feeds with influent E. coli ranging between 500 and 44,500 CFU/100 mL. Total disinfection was achieved with both disinfectants, however, the effectiveness of the chemical disinfectants in E. coli removal was affected by the quality of water to be disinfected. The study showed that turbidity plays a major role in disinfection performances by increasing chlorine demand on water sources with high turbidity levels.
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    Membrane fouling characterization in membrane-based septic tank
    (Taylor and Francis, 2013-04-15) Ali, Saadat; Pillay, Visvanathan Lingamurti; Khan, Sher Jamal; Visvanathan, C.
    Septic tank is a conventional on-site wastewater disposal system providing only primary treatment (settlement of solids), while offering little biological degradation. To further improve the quality of treated water, the conventional septic tank can be modified by the introduction of membrane module capable of effective rejection of suspended solids as well as associated particulate organic matter. However, membrane fouling by partially-treated water can be considered as one of the major limitations of the membrane-based septic tank (MBST) system. The present study was carried out in a pilot-scale MBST by using flat-sheet woven fiber microfiltration (WFMF) membrane modules. WFMF membrane module having 1 m2 effective filtration area was submerged in septic tank of 4 m3 working volume and operated at different fluxes to investigate the fouling frequency and effects of cleaning protocols. It was found that the physical cleaning protocol was effective in removing cake as well as partial pore blocking resistance without requiring chemical cleaning. On the other hand, after each operation cycle, the irreversible fouling of membrane increased.