An optimal operating strategy for fixed-bed bioreactors used in wastewatertreatment

Optimization of a fixed-bed bioreactor used in wastewater treatment is addr essed. The objective of optimization is to maximize the treatment efficienc y of the biofilter by manipulating the feed flow rate while satisfying oper ational constraints. Numerical results indicate that the optimal input is c haracterized as being on the boundary of the admissible region. Thus, the c haracterized optimal solution is implemented using a simple feedback contro l law, which provides the optimal input profile despite variations in subst rate inlet concentration and biomass growth rate. (C) 2001 John Wiley & Son s, Inc.