猪场粪污厌氧发酵前后理化特性及重金属含量变化分析

Analysis on Changes of Physicochemical Property and Heavy Metal Content of Pig Manure before and after Anaerobic Fermentation

为获得不同月份猪场粪污经过厌氧发酵后污染物去除效果、沼液养分及重金属含量变化情况,对沼气工程进出料口液面以下20 cm粪污、沼液分别于3月,6月,8月进行采样检测分析氮,磷,钾,CODCr,BOD5以及重金属含量等指标。结果表明,不同月份进入沼气工程的粪污及出料口沼液中氮、磷、钾含量表现出较大差异。沼液中氮主要以氨态氮形式存在,钾主要以可溶性钾存在。粪污经厌氧发酵处理后,CODCr去除率为81.2%-95.0%,BOD5去除率为81.3%-96.2%。对比《农田灌溉水质标准》（GB5084-92）重金属限量标准,8月沼液中汞、锌、铜含量分别超标60%,26.5%,41%。6月和8月沼液砷含量分别超标260%,280%。沼液中铬、镉、铅含量在允许范围内。

Samples were taking from both inlet and outlet of a pig manure digestion system in different month of March, June and August, and N, P, K, CODc,, BOD5 and the heavy metal content were determined. The results showed that the contents of N, P, K were obviously different between the different month and between the inlet and outlet waste. Nitrogen existed mainly in the form of ammonia nitrogen and potassium existed mainly in the soluble form. After anaerobic digestion, the C ODcr removal of pig manure was 81.2% - 95%, the BOD5 removal was 81.3% - 96.2%. But the mercury, zinc, copper content exceed the national standard of irrigation water quality（GB5084-92） by 60%, 26.5% and 41% respectively for the biogas slurry from outlet in August, and arsenic content exceed by 260% in June, and exceed by 280% in August. The chromium, cadmium and lead content were in the permission scope.