Performance of anaerobic stage-constructed wetland integrated in treatment of low-concentration domestic sewage

摘要

Prompted by the constructed wetland without long-term stable operation and anaerobic baffled reactor (ABR) with higher suspended solid (SS) removal rate, an anaerobic stage-constructed wetland integrated sewage treatment system was designed and applied to treat low-concentration domestic sewage from campus. The hydraulic retention times (HRTs) of anaerobic stage and constructed wetland were set as HRT_1, HRT_2 by our research. All the trials lasted 30 months, and the results of trial indicated that SS removal rate of the ABR stage was at least 82% under the condition that HRT_1 >=20h. At ( 22±2) °C, under the conditions that HRT_1=45h and HRT_2=15h, the COD, TN, TP removal rates of integrated wastewater treatment system could be over 82.38%, 76.75% and 71.29%, respectively. Based on the results of trial, the operational life of constructed wetland integrated with ABR was evaluated that at least 4 times than that of individual constructed wetland, and the mechanisms of higher efficacy and long-term stable operation of integrative sewage treatment system in treatment of low-concentration domestic sewage from campus were owed to high efficient SS removal rate at ABR stage.