硫铁矿人工湿地对微污染水源的水质净化效果

为进一步提升人工湿地在微污染水源条件下的同步脱氮除磷能力,以硫铁矿作为湿地填料设计构建了人工湿地装置,并采用挂膜法对硫铁矿进行硫自养型反硝化细菌表面负载,在此基础上研究硫铁矿人工湿地对水体中污染物的去除规律和去除机理,并通过高通量基因测序技术分析硫铁矿表面微生物的群落结构。结果显示,从UASB活性污泥中筛选出的硫自养型反硝化菌活性最高,脱氮效果最好;在微污染水源条件下,硫铁矿潜流人工湿地具有较好的同步脱氮除磷能力,在水力停留时间为60 h条件下,其对水体中的化学需氧量(COD_Cr)、氨氮(NH₃-N)、硝态氮(NO₃-N)、总氮(TN)、总磷(TP)的平均去除率分别达到53.5%、60.9%、67.2%、49.2%、46.3%;矿石表面发现菌群群落达到13门以上,变形菌门(Proteobacteria)为矿石表面最为优势的功能微生物菌群,相对丰度比例占45%左右,硫杆菌属(Thiobacillus)为自养反硝化脱氮的主要功能菌属。研究表明,采用硫铁矿作为填料可显著提高人工湿地的脱氮除磷效果,对微污染水体有较好的水质净化效果,以硫源作为反硝化过程的电子供体可以提高低碳源条件下系统的反硝化效果。

Purification Effect of Constructed Wetland on Micro-polluted Water Sources by Using Pyrite Cinder as Filler Media

In order to further improve the capacity of removing nitrogen and phosphorus simultaneously of constructed wetlands, A vibrating subsurface flow constructed wetland device was constructed using pyrite as a wetland filler. The surface loading of sulphur autotrophic denitrifying bacteria was carried out by using the membrane method. On the basis of this, the removal rules of COD, ammonia nitrogen, nitrate nitrogen, total nitrogen and total phosphorus in the water by pyrite subsurface flow constructed wetland was studied. Regularly, the mechanism of nitrogen and phosphorus removal was analyzed. And the community structure of microbes on the surface of pyrite was analyzed by high-throughput gene sequencing technology. The results show that the sulfur autotrophic denitrifying bacteria screened from UASB activated sludge has the highest activity and the best effect of removing nitrogen. Under micropolluted water source conditions, pyrite subsurface flow constructed wetland has good capacity of removing nitrogen and phosphorus simultaneously. Under the condition that the hydraulic retention time is 60h, the average removal rates of COD, ammonia nitrogen, nitrate nitrogen, total nitrogen and total phosphorus in water are respectively 53.5%, 60.9%, 67.2%, 49.2%, 46.3%. On the surface of the ore, more than 13 phylums were found. Proteobacteria was the most dominant functional microbial flora on the ore surface. The relative abundance ratio was about 45%. Thiobacillus is the main functional genus of autotrophic denitrification. The study has shown that the use of pyrite as a wetland filler improves significantly the effect of removing nitrogen and phosphorus and has a better water purification effect on micro-polluted water. It can improve the denitrification effect that elects the sulfur source as the electron donor of the denitrification process under low carbon source conditions.