Fuzzy - Based Multi - Criteria Decision Support System for Maintenance Management of Wastewater Treatment Plants

Wastewater treatment plants (WWTPs) contain a large number of components, and these components in turn require a large number of maintenance activities and high costs. In this paper, a Fuzzy-based Multi-Criteria Decision Support System (FBMCDS) model was designed based on the failure mode and effect analysis FM-EA and applied to the Rustumiya Project (RP) in Iraq. Information of the RP’s components, failure modes, applied maintenance activities and costs were collected from the documented data, site visit and face-to-face interviews as well as opinions of 44 experts. Through applying the fuzzy logic to analysis the failure modes and effects, the risk priority index (FMRPI) and total intensity (FMTI) of each failure mode ware computed. Thus, maintenance priorities and weights of the RP’s failure modes were specified. In addition, the best maintenance plan was specified based on the FMRPI-FMTI diagram that shows the importance and the type of maintenance required for each failure mode. Failure of the submersible pump has the first rank in terms of priority, while the last priority was occupied by the building failure mode, where the mechanical failure modes are of the highest importance, followed by the electrical failure modes. Finally, the construction failure modes are ranked last due to the small probability of failure. The designed model is considered an efficient tool due to the similarity of the results with the reality of the situation and the ease of reading and displaying the results. In addition, this model can be applied to other projects such as water treatment plants and irrigation projects.