Risk analysis of water treatment plant using fuzzy-integrated approach

Abstract

The study addresses and expounds the identification and prioritization of various causes of failure in the water treatment plant of an organization. The water treatment plant was being studied under the guidance of plants management team and data was collected. For identification of various causes of failure, fishbone diagram or cause and effect method has been used. A total of 16 causes of failure have been identified as a potential risk. The failure mode and effect analysis FMEA and Fuzzy methodology has been used for the proposed study. For FMEA, risk priority number (RPN) is used to prioritize failure causes. The uncertainty due to imprecise and vague expert judgment has been removed using fuzzy methodology. If-then rules are made in fuzzy inference system (FIS), and fuzzy RPN (FRPN) is obtained as output. The outputs of both methods are compared to get correct analysis. The average FRPN is evaluated as 5.375, that indicated that 4 out of 16 failure causes are critical for the system and require immediate and stringent attention from the maintenance department. The iron membrane filter, media filter choke acid dosing, sand/multimedia filter are identified as prominent causes of failure. Finally, the present methodology, under multiple sources of different and uncertain evaluation information is used to assist maintenance personnel for proper maintenance planning, reducing risks, improving the efficiency of the system and reducing the cost of the installation in water treatment plant.