反硝化抑制硫酸盐还原的工艺特性  

Characteristics of Denitrification Inhibiting Sulfate Reducing Process

作　　者：金鹏康[1] 杨珍瑞 李蓉[1,2] 李岩[3] 周立辉[3] 

机构地区：[1]西安建筑科技大学环境与市政工程学院,西安710055 [2]包头市财政性投资评审中心,包头014030 [3]中国石油长庆油田公司油气工艺研究院,西安710055

出　　处：《环境科学》2017年第5期1982-1990,共9页Environmental Science

基　　金：国家自然科学基金项目(50978211)

摘　　要：本实验通过建立一套两级串联UASB反应器研究油田集输系统及高含盐量废水中反硝化抑制硫酸盐还原的工艺处理特性,并在工艺稳定运行后对形成的颗粒污泥性状及微生物特性进行研究.结果表明,添加Na NO2可促使反应体系中反硝化细菌(denitrifying bacteria,DNB)数量由7.0×103CFU·(100 m L)^(-1)增加至7.3×105CFU·(100 m L)^(-1)并保持稳定,DNB对硫酸盐还原菌(sulfate-reducing bacteria,SRB)的竞争抑制作用导致SRB数量由8.0×105CFU·(100 m L)^(-1)减少,稳定至7.6×104CFU·(100 m L)^(-1),同时,硫酸盐还原过程被抑制,硫离子的抑制率不断增加,最终稳定至82%.生物量与亚硝酸盐的质量比为1 200时,反应体系对S2-的抑制率最高,达到92%,可实现较好的硫酸盐还原过程抑制效果;该工艺对其抑制率可保持在92%左右,具有较好的稳定性.形成的反硝化颗粒污泥为棕褐色,基本为椭球形和球形,表面光滑且密实.反硝化抑制前,颗粒污泥的粒径多分布于1.0~1.4 mm,平均粒径为1.17 mm,经反硝化抑制后,粒径多分布在1.2~1.6 mm,平均粒径为1.21 mm,反硝化抑制过程促进污泥粒径的小幅增加;形成的反硝化颗粒污泥平均沉速为47.6 m·h^(-1),沉降性能较好.PCR-DGGE分析结果表明,反硝化抑制作用使微生物菌种由18种减少至14种,优势菌种由4种减至3种,多样性降低,反硝化抑制前后微生物种群相似性为62.6%,种群结构发生较大改变,优势菌群由SRB演变为DNB,SRB优势菌种由4种减至2种,同种菌的丰度明显降低;反硝化抑制过程的主要功能菌为Uncultured Sulfurimonas sp.,是一种自养型反硝化细菌,与SRB抢夺电子并占优势,抑制硫酸盐还原过程及SRB生长繁殖,从而抑制硫化物的产生.In this study, a set of two-stage UASB reactor was used to study the characteristics of denitrification inhibiting sulfate reduction in oil field gathering and transportation system and some high salt wastewater, and the characteristics of granular sludge and microbial characteristics were studied after the stable operation of the process. The results showed that the addition of NaNO2 increased the number of denitrifying bacteria （DNB） from 7.0×10^3 CFU·（100 mL）^-1 to 7.3×10^5 CFU·（100 mL）^-1 and remained stable in the process from start to mature. The competitive inhibition caused by DNB decreased the number of SRB from 8.0×10^5 CFU·（100 mL）^-1 to 7.6×10^4 CFU·（100 mL）^-1. Meanwhile, the sulfate reduction was inhibited, and the inhibition rate increased and finally stabilized to 82%. The study on mass ratio of microbial mass to nitrite effecting on denitrification efficiency showed that the inhibition rate of S^2- was the highest, reaching 92%, when the mass ratio was 1200. The inhibition rate of the process could remain at about 92%, with good stability. The particle size and sedimentation rate of granular sludge were measured to determine whether the process conditions were favorable for the formation of granular sludge. The study showed that the denitrifying granular sludge formed was brown, basically ellipsoidal and spherical, with smooth surface and high density. Before the denitrification inhibition, the particle size of granular sludge was 1.0-1.4 mm and the average diameter was 1.17 mm, and after denitrification inhibition, the particle size distribution was 1.2-1.6 mm, the average particle size was 1.21 mm, which indicated that the denitrification inhibition increased the size of granular sludge. The average sedimentation velocity of denitrifying granular sludge was 47.6 m·h^-1, which revealed the good settling performance of the granular sludge. The results of PCR-DGGE analysis showed that the denitrification inhibition reduced the number of microbial species from 18 to 14

关 键 词：反硝化 硫酸盐还原菌(SRB) 反硝化细菌(DNB) 颗粒污泥 PCR-DGGE 

分 类 号：X703.1[环境科学与工程—环境工程]