Multi-Criteria Design and Evaluation of Reverse Osmosis Desalination Systems, Case Study: the University of Tabriz Qanat

In recent years, reverse osmosis method has played a major role in desalination of brackish and saline waters. The purpose of this study is to provide a proper desalination system for the use of aqueduct water in the University of Tabriz for health consumption in order for proper water management. According to the results of qualitative experiments, in the first step, the reverse osmosis desalination system was selected and designed. Through that, according to the different types of membranes and pre-purifiers, 15 scenarios were evaluated by 4 main criteria (economic, technical, environmental and social) and 6 sub-criteria. With the help of water application value engine (WAVE) software, the scenarios were modeled based on the opinion of decision makers and the weight of each criterion was calculated. Finally, group fuzzy decision making (GFDM) software was used to analyze group multi-criteria decision making to determine the best scenarion. In this study, by combining the WAVE and GFDM software the opinions of officials and experts are directly applied in the design and selection of the treatment system, leading to increase in the users’ satisfaction. Finally, the results show that the M scenario is the best choice of the decision-makers' point of view, which includes XLE-440 membranes for reverse osmosis and SFD-2880 ultrafiltration filter. In addition, to more accurately examine the behavior of the scenarios, sensitivity analysis on the parameters has also been performed.