Pilot research on treatment of low concentration domestic wastewater by hydrolysis, bio-ceramic moving bed and coagulation combined process
水解-BCMBBR-混凝沉淀组合工艺处理低浓度污水的中试研究

A hydrolysis-bioceramic moving bed biofilm reactor(BCMBBR)-chemical coagulation combined process was developed for treatment of domestic wastewater with low organic carbon concentration and high ammonia-N levels(COD 110~140 mg/L,C/N 4~5) in Dongguan city,China.The results showed that successful start-up of the BCMBBR can be achieved in 20 days.Without incorporating chemical coagulation,the BCMBBR can remove more than 81% of the COD,NH+4-N and SS and 47% of the TN with an hydraulic retention time of 8 h,gas-water ratio of 5∶ 1 and mixture reflux ratio of 150%.But TP removal efficiency was low.When chemical coagulation(enhanced coagulation based on the addition of PAC and PAM) was incorporated into the BCMBBR,TP removal was significantly enhanced.The TP concentration in effluent was less than 0.5 mg/L which can meet the first class A discharge standards for phosphorus for municipal wastewater treatment plant of China.Aeration intensity has a direct effect on the microbial diversity in the BCMBBR system which could be a useful indication for regulating aeration intensity and thus,high efficient operation of the BCMBBR can be achieved.The unit operating cost of the hydrolysis-BCMBBR-chemical coagulation combined process was only 0.24 yuan/m3 which present an economical and effective approach for treatment of low strength domestic wastewater containing low total organic carbon to nitrogen ratios in south of China.