Use of COPRAS decision model for the selection of best treatment alternatives in removing micropollutants: Diclofenac example

Abstract

Diclofenac (DCF) is one of nonsteroidal anti-inflammatory drugs that is not effectively removed in drinking water and wastewater treatment plants. In recent times, DCF has been found in many drinking water sources, highlighting the increasing need to enhance current wastewater and drinking water treatment facilities through advanced treatment technologies to efficiently eliminate DCF and other micropollutants. Nonetheless, selecting the best treatment technologies is a complex matter in this modernization process, requiring multidimensional thinking and multi-criteria decision-making. This study introduces a new approach with defined multi-dimensional evaluation criteria and a multi-criteria decision-making method for choosing the best treatment alternatives and technologies. This new approach was applied and tested to determine the best treatment alternatives for DCF, one of the emerging micropollutants in this study. In this context, a total of 18 evaluation criteria were determined and prioritized. A thorough literature review was conducted to identify and assess the performance of the treatment alternatives. In determining these alternatives, the "complex proportional assessment (COPRAS)" analytical decision-making method was used in the decision-making process and their priority rankings were determined. The final priority order was determined as membrane filtration > adsorption > hybrid processes > advanced oxidation processes > artificial wetlands > oxidation processes > conventional treatment processes > biological treatment > other treatment processes. Membrane processes were discovered to be the most effective tertiary treatment alternative for DCF removal. If membrane processes are preferred as tertiary treatment in a treatment plant, the application of concentrated management techniques such as volume reduction will further increase the environmental benefit.