Novel Two-Stage Three Phase Fluidized Bed Bioreactor with Immobilized Living Cells for Wastewater Treatment Application

摘要

The research investigated the fundamental, practical design and operation of a novel two-stage three-phase fluidized bed bioreactor for cost-effective waste-water treatment. Phenol biodegradation was selected as a model biodegradation system for the study. The fundamental studies included bubble wake structure and dynamics, solid mixing, gas-liquid mass transfer, biofilm characteristics, and biodegradation kinetics. Comprehensive mathematical models for steady state and dynamic phenol biodegradation in both draft tube and conventional three-phase fluidized bed bioreactors were developed and experimentally validated. These models provided guidelines for design, control and optimization of biodegradation processes in three-phase fluidized bed bioreactors. The two-stage bioreactor was demonstrated to successfully integrate immobilization, biofilm development, biodegradation and biofilm control functions into one single unit with the least human intervention. The performance of the two-stage bioreactor in terms of biodegradation rate per unit solid loading was shown to be superior to that of a one-stage three-phase fluidized bed bioreactor.