REAL-TIME EXPERT-SYSTEM CONTROL OF ANAEROBIC-DIGESTION

The objective of this research was to develop on-line measurement and feed-back control strategies for evaluation and optimization of a gluc ose-fed CSTR digester. Using methane yield as a direct on-line measure ment, a model and algorithm were developed and applied for feed-back c ontrol and adaptive optimization of the digester for temperature. The model and algorithm were modified and integrated into an expert system to use methane production rate and dilution rate to automatically det ect and recover digester abnormal performance resulting from underload ing, overloading, and addition of an inhibitor (phenol). Online fluoro metric measurement of NADH, which is a measurement of overall microbia l activity, was evaluated for its potential contribution to this contr ol strategy.