Feasibility Study of Treatment Technologies for Greywater to Enhance Water Security

摘要

Greywater can be viewed as an important resource which could be diverted for variety of application to water starved areas. With the increased challenges of freshwater availability, reliable alternatives like treated greywater need to be searched upon. Its constant availability throughout the year with low organic content makes it quite suitable and cost feasible for recycling and also a good source of water for augmenting water supply. Various Greywater treatment methods such as physical, biological, chemical, constructed wetland and combined treatment have been analysed in this paper for both Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) removal efficacy. Also the feasibility aspects of these technologies in terms of effluent generation, space consumption, financial viability, expertise required have been analysed with reuse perspective and it was found that the relatively simpler technologies like physical treatment and constructed wetlands are cost effective in treating greywater and are suitable for reuse in landscaping and flushing. Complex technologies like chemical and biological treatment technologies generate treated effluent suitable for stringent reuse applications. Social acceptance and awareness are some of the other aspects which need to be considered for enhancement of usage of such technologies.