Fault Diagnosis System of A2/O Process Based on Parameter Estimation and Expert System

Abstract

For urban sewage treatment process of A2/O, a fault diagnosis method based on parameter estimation of Activated Sludge Model No.2(ASM2) model and expert system is proposed. Firstly, the A2/O process is simulated based on Activated Sludge Model No.2(ASM2) model, according to which, the estimated value of component parameters of biochemical reaction process is obtained, and when it’s compared with the normal value of corresponding parameters, the faults can be detected. Furthermore, an expert system that can draw fault diagnosis results is designed by means of uncertainty reasoning for expert knowledge. Finally, a fault diagnosis system for A2/O process is developed. For a sewage treatment plant of Kunming, experiment result has shown that the fault diagnosis system for A2/O process can make effective diagnosis of the actual process issues, and it has certain engineering practicability.