北方地区奶牛养殖场粪污氧化塘还田处理法污染物削减核算

Total pollutants amount production and discharge calculation of large-scale dairy farms which return cattle manure to land after oxidation pond in Northern Region

畜禽养殖业中最为关键的两大环保问题是粪污处理和污染物总量削减。本文以呼和浩特市某公司为例,通过为期一年的实地调研和监测研究北方地区规模化奶牛养殖场氧化塘工艺粪污削减情况。结果表明:(1)试验牧场泌乳牛粪污COD产生系数为1424g/头.d,占国家核定系数的30%-49%,氨氮产生系数为22 g/头·d,达国家核定系数的2.5-2.8倍。(2)三级好氧发酵氧化塘对COD的处理效率为52.03%,而氨氮浓度却增加11.99%。(3)试验牧场通过氧化塘液体肥和堆肥还田的COD量占总产生量的比例为20.18%,氨氮为63.60%;通过回冲牛舍和垫料方式在系统内部循环的COD和氨氮量分别占总产生量的45.15%和71.81%;通过氧化塘和固液分离消减的COD占35.51%,而氨氮却增加30.74%;堆肥过程中COD和氨氮分别增加0.85%和4.67%。

The most important environmental issues are treatment of livestock and poultry manure and reductions of total pollutants amount in livestock and poultry industry. Through surveying and monitoring for one year, COD and ammonia nitrogen discharges and reductions were researched on a typical large-scale dairy farm which uses oxidation pond to treat waste water in northern region Hohhot. The results were as follows： （1） COD production coeffcient of lactation cow manure was 1424 gram per cow every day, accounted for 30%-49% of the national authorized coeffcient, and ammonia nitrogen production coeffcient was 22 gram per cow every day, up to 2.5-2.8 times the authorized coeffcient of the country. （2） treatment effciency of COD through three stage aerobic fermentation oxidation ponds was 52.03 %, while ammonia nitrogen concentration increased by 11.19% after three stage oxidation ponds. （3） 20.18% of COD and 63.60% of ammonia nitrogen were returned to the farm with the liquid manure and compost, and 45.15% of COD and 71.81% of ammonia nitrogen were internal reused through rushing supernatant liquid back to the barn and taking compost as cushion material. In the oxidation pond and solid-liquid separation process, COD decreased by 35.51%, while ammonia nitrogen increased by 30.74%. During composting, COD and NH3-N increased by 0.85% and 4.67%, respectively.