Seguiment d’una planta pilot de bioreactor de membranes (MBR) i validació del sistema de control basat en eines de lògica difusa per a l’optimització energètica

Abstract

Wastewater treatment plants treat water modified by humans in order to avoid contaminated water in the natural environment and maintain resilience in the water cycle. Conventional treatments carried out in these treatment plants make it possible to remove excess organic matter and pollutants from the water but have many limitations. These limitations can be overcome through the implementation of technologies that complement and optimize existing processes and, in the end, generate better quality of treated water. One of these technologies is the use of membrane bioreactor technology (MBR) applied to conventional sewage treatment plants. MBRs generate higher water quality and require smaller reactor volumes, but the membranes that make it up have fouling processes that decrease process efficiency. One of the most widely used systems for minimizing fouling, is based on creating turbulences by aeration on the membranes in order to clean them and improve efficiency. This process has a very high energy expenditure, and in the present study, two proposals for air-scour control systems to save energy have been studied. One of these systems is based on binary logic and has already been validated in real plants, while the other, based on fuzzy logic, has been developed and presented in this study. Finally, two responses of the decision support systems were tested, one proposal working with hourly time changes (proposing an air-scour modification every hour) and has been compared to daily changes. The results have shown greater savings potential with the use of the fuzzy logic-based control system over binary logic. In addition, when working with hourly responses, more savings were generated than in daily responses