不同絮凝剂用量对牛粪沼液固液分离产物的影响

Effects of Different Flocculant Amounts on Solid-Liquid Separation Products of Cow Manure and Biogas Slurry

为了探索模化养殖场沼液综合利用中存在的回收效果差、处理成本高、沼液固液分离精度低的问题,通过有效前处理对牛粪沼液进行分离成为行之有效的途径。为此,设置了7个前处理的絮凝剂用量,结果表明:处理六的效果最佳,处理1 t沼液需要添加的聚合氯化铝为0.5%,聚丙烯酰胺为0.3‰,成本为13.6元。其次是处理五,处理1 t沼液需要添加的聚合氯化铝为0.67%,聚丙烯酰胺为0.067‰,用40 kg干粪渣替代部分聚丙烯酰胺,成本为15.5元。通过前处理筛选,沼液COD、总磷、悬浮物去除率达到90%以上,氨氮去除率达到40%以上,对沼液固液分离起到了较好的作用,为后续膜过滤工艺和生物处理减轻了负荷。

In order to explore the problems of poor recovery effect,high processing cost and low accuracy of solid-liquid separation in the comprehensive utilization of biogas slurry in model farms,the separation of cow manure and biogas slurry through effective pretreatment has become an effective way.This paper sets seven pre-treatment flocculant dosages.The results showed that the treatment six has the best effect.Polyaluminum chloride needed to process one ton of biogas slurry is 0.5%;polyacrylamide is 0.3‰,and the cost is 13.6 yuan.The second is treatment five.The polyaluminum chloride needed to process one ton of biogas slurry is 0.67%,and the polyacrylamide is 0.067‰.40kg of dry manure is used to replace part of the polyacrylamide,and the cost is 15.5 yuan.Through pre-treatment screening,the removal rate of COD,total phosphorus,and suspended solids of the biogas slurry reached more than 90%,and the removal rate of ammonia nitrogen reached more than 40%,which played a good role in the solid-liquid separation of the biogas slurry,and was used for the subsequent membrane filtration process and biological treatment to reduce the load.