反渗透浓缩沼液预处理试验研究  

Pretreatment of Biogas Slurry for Its Concentrating by Reverse Osmosis

作　　者：梁康强[1] 朱民[1] 林秀军[1] 孙宇[2] 

机构地区：[1]北京市环境保护科学研究院,北京100037 [2]中国环境科学研究院,北京100012

出　　处：《中国沼气》2013年第2期8-10,20,共4页China Biogas

基　　金：国家高技术研究发展计划(863)项目(2007AA06Z345);"十一五"国家科技支撑计划项目(2008badc4b17)

摘　　要：采用反渗透膜工艺浓缩沼液,针对沼液悬浮物颗粒过大浓度过高、钙镁离子超标等问题,采取预处理手段对反渗透膜片进行保护,以保证系统的产水量和运行成本达到最佳。结果表明,在自然沉淀、混凝、离心过滤和滤袋过滤四种去除悬浮物工艺中,自然沉淀和离心过滤效果最佳,其出水悬浮物粒径均在10μm以下。通过自然沉淀时间优化,自然沉淀最佳时间为1天,既能保证出水效果,又能节省沉淀池容和投资。对于钙镁离子和硫酸根离子结垢,采用反渗透膜厂家提供配方,并智能化添加阻垢剂,长期运行结果证明,防结垢效果较好,平均碱洗周期为120 h,酸洗周期为360 h。There are some problems in biogas slurry concentrating by reverse osmosis method, which related to the suspended solid, calcium and magnesium ions in biogas slurry, for the diameter of suspend solid is too long and the concentration is too high, and both calcium and magnesium contents were exceed the standard. Accordingly, the pretreatment process protecting the reverse osmosis membrane is put forward in this paper so as to ensure the maximum water production and least operation cost. The results showed that, among the methods of natural precipitation, coagulation, centrifugal filter and bag filter processe, the natural sedimentation and centrifugal filtration had the best effectiveness, for the particle size of sus- pended solids in pretreated biogas slurry was smaller than 10 μm. Through optimization,the best precipitation period was 1 day. In this way, not only the water production could be guaranteed, but also sedimentation tank volume could be smaller and investment cost could be lower. As for the calcium, magnesium and sulfate ion scaling, formula was provided by osmosis membrane manufacturers and intelligent scaling inhibitor was added. The long-term operation results showed well antiscaling performance. The average alkali-wash cycle was 120h and pickling cycle was 360 h.

关 键 词：预处理 沼液 反渗透 膜浓缩 

分 类 号：X506[环境科学与工程—环境工程] S216.4[农业科学—农业机械化工程]