Anaerobic-aerobic treatment of low strength domestic wastewater and trinitrophenol wastewater.

摘要

This research targeted two prominent issues in wastewater treatment, the treatment of low strength domestic wastewater in older, inefficient wastewater treatment plants, and the treatment of hazardous industrial wastewater containing nitro-aromatic compounds using trinitrophenol (TNP) as the representative. To these ends, the Anaerobic Expanded Bed Reactor (AEBR) - Sequencing Batch Reactor (SBR) process, an innovative hybrid anaerobic-aerobic system, was evaluated. It was shown in this research that the AEBR could effectively treat very low strength domestic wastewater (50 mg/L COD) under very low temperature conditions (5{dollar}spcirc{dollar}C) and it did not exert any adverse impact on the downstream SBRs in terms of carbonaceous removal (including individual organic compounds), anion transformation, or sludge generation and settleability. The AEBR performance made the anaerobic-aerobic process possible and feasible for low strength domestic wastewater treatment. To exploit the possibility of using the AEBR-SBR system for the treatment of industrial wastewaters containing nitroaromatic compounds, Enterobacter taylorae, a facultatively anaerobic rod, was isolated from the Potsdam Wastewater Treatment Plant. This strain can transform TNP in the presence of organic compounds and nutrients in addition to TNP. It could tolerate TNP at a concentration as high as 1000 mg/L, and its growth kinetics did not significantly change at concentrations between 0 and 500 mg/L. TNP transformation was through a reduction pathway and aminonitrophenols were formed which could be polymerized and potentially separated from wastewaters. All of these features make it a feasible candidate for the anaerobic-aerobic treatment of wastewater containing TNP.