生物膜法A^2/O^2焦化废水处理系统中好氧反应器工艺特性

Pilot-scale experiment of the aerobic reactor technology in bio-film A^2/O^2 system for coking wastewater treatment

以焦化厂废水处理系统气浮设备出水为水源,在中试规模上研究了生物膜法A2/O2系统中好氧反应器的工艺特性和效果。研究结果表明,系统进水COD为1000～2200mg/L,NH3-N质量浓度为200～400mg/L,水解酸化反应器HRT为20h,缺氧反应器HRT为24h,一级好氧反应器和二级好氧反应器HRT均为48h,二级好氧反应器硝化液回流比为3,一级好氧反应器COD容积负荷为0.40kg/(m3·d),二级好氧反应器COD容积负荷<0.07kg/(m3·d),NH3-N容积负荷为0.022kg/(m3·d)时,生物膜法A2/O2系统处理出水COD和NH3-N浓度可以同时达到《污水综合排放标准》(GB8978—1996)中的一级排放标准。

On the basis of pilot-scale experiment,the characteristics and efficiency of the aerobic reactors in bio-film A^2/O^2 system have been studied,taking the effluent water from an air-flotation equipment of wastewater treatment system at a coking plant as watewater source. Research results indicate that when the COD of the system influent water is between 1 000-2 200 mg/L,the influent NH3- N fluctuates between 200-400 mg/L,the HRT of hydrolysis- acidfication reactor, anoxic reaction, the first aerobic reactor and the second aerobic reactor are 20,24,48 h respectively,the nitrifying recirculation ratio is 3 ,the first aerobic and second aerobic reactor COD loading rate are 0.40 and 0.07 kg/（m^3·d） respectively,and the second aerobic reactor NH3-N loding rate is 0.22 kg/（m^3·d）,the COD and NH3-N of discharged water can reach the first grade of Comprehensive Wastewater Discharge Standard（GB 8978- 1996）.