【摘要】 常规生化/物化组合工艺常被中、大型养殖场用于其废水达标排放处理,但长期运行效果和经济性却鲜有报道。以广东惠州某5万头猪场已运行10多年的污水处理站为研究对象,进行了连续3个多月现场采样,重点跟踪测定各单元进、出水水质,以探究其实际处理效果、存在问题及其原因。结果表明:猪场废水的有机物含量高,COD、NH₃-N、TN和TP浓度最高达到15 875、1 680、1 838和1 022 mg/L;经常规A/O生化处理后,COD、NH₃-N、TP浓度仍达到646. 9～1 593、130～573、43. 5～103. 2 mg/L,不能达标,需进行物化处理;通过芬顿高级氧化和化学混凝处理后,出水COD和TP浓度可稳定达标,但氨氮浓度仍在150 mg/L以上,明显超标;运行成本高,直接运行成本达到17. 8元/m³。研究还发现,猪场废水处理难以达标的主要原因在于废水中SS浓度太高,使水中COD和磷大都以颗粒态或"惰性"形态存在,溶解性COD和磷相对较少,相对较难生化完全;此外,沼液在A/O生化单元的停留时间较短也是重要原因。因此,设法在进入生化池前尽可能地去除SS,使进入生化池废水的污染物主要以溶解性组分为主;通过扩大池容等方式适度延长水力停留时间,可有效提高处理效率和降低处理成本。更多还原

【Abstract】 The conventional biochemical/physicochemical combined process is often applied to treat swine wastewater. However,information on the practical treatment efficiency and costs in long-term operation is limited. Quality of the influent and effluent from different treatment units at Huizhou Swine Wastewater Treatment Station （HSWWTS） located in Guangdong Province was investigated for more than three consecutive months. HSWWTS had been using a combined biochemical and physicochemical processes,namely A/O and Fenton reaction,for more than ten years. It was observed that the highest concentrations of COD,NH₃-N,TN,and TP in the tested swine wastewater reached 15 875 mg/L,1 680 mg/L,1 838 mg/L and 1 022 mg/L,respectively. The effluent COD,NH₃-N and TP from the conventional biochemical unit were in ranges of 646. 9-1 593 mg/L,130-573 mg/L,and 43. 5-103. 2 mg/L,which failed the discharge standard. Fenton reaction followed by the chemical coagulation was applied to further treat the effluent from the secondary clarifier. NH₃-N was not substantially removed and more than 150 mg/L in effluent,although the effluent COD and TP completely met the standard. Furthermore,the operational cost of using such a combined process was as high as 17. 8 yuan/m³. It was found that high concentration of SS was the major obstacle for the effluent to meet the discharge standard. As a result,most COD and P in swine wastewater existed in the forms of granular or"inert"COD and P,which was too difficult to be biodegraded by activated sludge. In addition,the short HRT of anaerobic fermentation slurry in the A/O biological treatment unit reduced the removal efficiency of pollutants. Therefore,to improve the effluent quality,a critical strategy was to completely remove SS before anaerobic fermentation swine slurry entered the A/O biochemical treatment unit. Enlarging the tank volume of the A/O unit could extend HRT,which should be considered as well.更多还原