Municipal wastewater reclamation for non-potable use using hollow- fiber membranes

Approximately 80% of water used in urban areas reappears as municipal wastewater (MWW). Reclamation of MWW is an attractive proposition under the present scenario of water stressed cities in India. In this paper, we attempted to reclaim MWW using lab-scale hollow- fiber (HF) membrane modules for possible reuse in non-potable applications. Experiments were conducted to evaluate the efficiency of virgin HF (M1) and modified HF (M2) modules. The M2 module consists of HF modified with a skin layer formed through interfacial polymerization of m-phenylenediamine with trimesoyl chloride (MPDTMC). The molecular weight cut-off (MWCO) of M1 was 44000 g/mol and that of M2 10000 -14000 g/mol on the basis of rejection of polyethylene glycol. The combination of M1 and M2 modules was able to reduce concentrations of most of the pollutants in sewage and improved the treated water quality to the acceptable limits for non potable reuse applications. It is found that about 98-99% of the initial flux is recovered by the backwashing process, which was approximately two times in a month when operated continuously.