Determination of the Most Effective Process Control Parameters of Activated Sludge, and Investigating the Process Performance in Unconventional Loading Using Hybrid Numerical Solution of Benchmark Simulation Model No. 1 (BSM1)

The main goal of controlling urban wastewater treatment plants is to adopt an algorithm in which the process works in optimal operating conditions. For this purpose, we need to use the process mathematical model. In this study, the steps of building the enchmark Simulation Model No. 1 (BSM1) were presented step by step. Appropriate numerical methods were proposed for solving the simulation model, and the most effective parameter of the process was determined to provide control strategies. Finally, behavior of the process was examined against different weather conditions. The initial values inside the reactors and the clarifier layers were calculated by solving the state equations of each reactor. Using the Euler and Range Kutta hybrid numerical approach, the BSM1 simulating model was created in MATLAB environment. By applying different weather conditions, the behavior of the treatment process was investigated. Findings: Applying more than one numerical solution to solve the simulation model reduced significantly the amount of additional calculus and time, as a very important item in predictive controlling systems. Make use of different control strategies, necessarily do not improve the quality of all process parameters. Nitrogen-containing parameters, especially ammonia nitrogen, are the most effective control parameters in activated sludge process. This process complies effluents standard limits of chemical oxygen demand (COD), 5- day biological oxygen demand (BOD5), and total suspended solids (TSS) with significant difference. Only in nitrogen parameter, we see some violations of the standard. The model that is created for the first time in the country can be used for different purposes in the fields of process recognition and operation.