规模化奶牛场废水处理工艺参数优化及效果分析

Parameter Optimization and Efficiency Analysis of Cattle Farm Wastewater Treatment Process

采用USR+两级A/O组合工艺处理奶牛场干清粪养殖废水,出水水质稳定达到《农田灌溉水质标准》(GB 5084—2005),并优于《畜禽养殖业污染物排放标准》(GB 18596—2001)。针对该类废水中TN含量高、厌氧消化后COD/TN值低、后续好氧对TN去除率不高的问题,进行了一系列的工艺调整研究。结果表明,在不改变构筑物、不增加投资的条件下,通过强化固液分离、混合原水等措施可提高TN去除率,TN去除率由77.5%提高到85.9%,对BOD5、COD、SS、NH3-N、TP的去除率也分别达到98.2%、98.3%、98.7%、90.5%、93.2%,可为同类奶牛场干清粪养殖废水的处理提供借鉴。

The combined technology of USR and two-stage A/O process was adopted for treatment of cattle farm wastewater. The effluent quality could meet the requirements in the Standards for Irrigation Water Quality （ GB 5084 - 2005 ） and was superior to the requirements in the Discharge Standard of Pollutants for Livestock and Poultry Breeding （ GB 18596 - 2001 ）. To address the problems of high concentration of TN, low C/N ratio after anaerobic digestion and low removal rate of TN in the two-stage A/O process, a series of process adjustment experiments were carried out. The results showed that without changing the original structures and without adding investment, the removal rate of TN could be improved by taking measures such as strengthening the solid-liquid separation and adding raw wastewater. The removal rate of TN was increased from 77.5% to 85.9%. The removal rates of BODs , COD, SS, NH3 - N and TP were 98.2%, 98.3%, 98.7%, 90.5% and 93.2%, respectively. The results can provide reference for treatment of wastewater from similar cattle farms.