SELECTION OF COST EFFECTIVE WASTE WATER TREATMENT TECHNOLOGY

Abstract

Various technological alternatives for waste water treatment are available ranging from conventional methods to advance treatment methods. Selection process often diddles decision makers specially when multiple factors in selection of appropriate technology need to be considered. In this study, a holistic decision making approach has been developed for sustainable development considering multiple factors ranging from economic parameters to social and environmental parameters. In this study, Capital cost, operation and maintenance cost, land requirement depicts the economic concern of selection procedure and Global warming potential, Eutrophication potential depicts environmental concern and to take into account social concern robustness of system and sustainability criteria have been incorporated. Suitability of any technology largely depends upon the location of the plant, land availability and objectives of the treatment etc. or in other words it depends on the scenario for which plant need to be constructed. So for this aspect to take into account four scenario have been formulated to capture regional and local societal priorities of suburban and urban areas. Three most commonly used waste water treatment technologies viz. Sequential batch reactor (SBR), Activated sludge process (ASP) and Up flow sludge blanket- Final polishing pond (UASB-FPP) have been evaluated in this study. Commonly used multiple attribute decision making approach TOPSIS has been selected for ranking the alternatives. Among the three technologies considered for the assessment, SBR was identified as the most suitable alternative for all four scenarios not only because SBR has low land requirements and having less life cycle cost per MLD compared to other two technologies but SBR produces considerably good effluent quality also.