臭氧催化氧化-BAF组合工艺深度处理抗生素制药废水

Advanced treatment of antibiotic pharmaceutical wastewater by catalytic ozonation combined with BAF process

针对抗生素制药废水组分复杂、毒性强、难生物降解的特点,以Ce负载天然沸石作为催化剂(Ce/NZ),采用臭氧催化氧化-曝气生物滤池(BAF)组合工艺对抗生素制药废水二级生化处理出水进行深度处理。结果表明,Ce/NZ催化剂可显著改善臭氧预处理单元的处理效率,在臭氧进气浓度为50 mg·L-1、臭氧进气量为600 mL·min-1、催化剂用量为1 g·L-1、臭氧反应时间为120 min的条件下,臭氧催化氧化预处理对抗生素制药废水的COD去除率达到43%,平均COD由220 mg·L-1降至125 mg·L-1,BOD5/COD由0.12升至0.28,废水的可生化性得到显著提高。臭氧预处理单元出水采用BAF进行生化处理,在进水平均COD为125 mg·L-1、平均NH4+-N为12 mg·L-1、水力停留时间为4 h、气水比为4∶1的条件下,COD和NH4+-N的平均去除率分别为62%和64%。组合工艺处理后出水平均COD和NH4+-N分别为46 mg·L-1和4.1 mg·L-1,出水水质可以稳定达到《发酵类制药工业水污染物排放标准》(GB 21903-2008)。相较于单独BAF工艺,组合工艺出水COD和NH4+-N平均去除率分别提高了66%和15%,出水水质明显优于单独BAF工艺出水。

In view of the complex,toxic and difficult biodegradation of antibiotic pharmaceutical wastewater,the Ce-loaded natural zeolite was used as a catalyst(Ce/NZ),and the ozone-catalyzed biological aerated filter(BAF)combination process was applied to advanced treatment of the secondary biochemical treatment effluent of antibiotic pharmaceutical wastewater.The results showed that the Ce/NZ catalyst could significantly improve the treatment efficiency of the ozone pretreatment unit.With the ozone inlet concentration of 50 mg·L-1,the ozone intake of 600 mL·min-1,the catalyst dosage of 1 g·L-1 and the ozone reaction time of 120 min,the COD removal rate of antibiotic pharmaceutical wastewater reached 43%,the average COD value was reduced from220 mg·L-1 to 125 mg·L-1,and the BOD5/COD increased from 0.12 to 0.28,during which the biodegradability of wastewater was significantly improved.The effluent of the ozone pretreatment unit was biochemically treated by BAF.At average influent COD value of 125 mg·L-1,the average influent NH4+-N concentration of 12 mg·L-1,the hydraulic retention time of 4 h,and the gas to water ratio of 4∶1,the average removal rates of COD and NH4+-N were 62%and 64%,respectively.After the combined process treatment,the average concentrations of NH4+-N in the effluent were 46 mg·L-1 and 4.1 mg·L-1,respectively,and the effluent water quality could stably meet the Discharge Standards of Water pollutants for Pharmaceutical Industry Fermentation Products Category(GB 21903-2008).Compared with the BAF process alone,the average removal rates of COD and NH4+-N in the effluent of combined process increased by 66%and 15%,respectively,and the effluent quality was significantly better than that of the BAF process alone.