摘要
硫酸盐还原菌(SRB)的生长代谢可导致油藏酸化,进而引发一系列环境和腐蚀等问题.硝酸盐(NO-3)补加及对硝酸盐还原菌(NRB)的调控是抑制SRB活性进而控制油藏酸化的重要策略.本研究从大庆油田水驱采出液中分离筛选出了1株兼性自养的NRB菌株DNB-8,并分析了在有机碳源充足的条件下不同浓度的NO-3结合使用该菌株抑制SRB富集培养物SO2-4还原活性的作用效果与机制.结果表明,浓度≤1.0 mmol·L-1的NO-3无法抑制SRB的SO2-4还原活性;NO-3浓度>1.0mmol·L-1或NO-2浓度>0.45 mmol·L-1均可有效抑制SRB的SO2-4还原活性.此时,NRB对有机碳源的竞争以及在利用NO-3的同时产生的NO-2是抑制SRB活性的主要机制.另外,大庆油田采出水中SRB富集培养物的细胞内存在异化NO-3还原生成NH+4的代谢途径(NO-2为中间产物).当NO-3浓度较高时,SRB可能通过该代谢途径减轻NO-2引起的抑制效应.
Growth and metabolic activity of sulfate-reducing bacteria （SRB） can result in souring of oil reservoirs, leading to various problems in aspects of environmental pollution and corrosion. Nitrate addition and management of nitrate-reducing bacteria （NRB） offer potential solutions to controlling souring in oil reservoirs. In this paper, a facultive chemolithotrophic NRB, designated as DNB-8, was isolated from the produced fluid of a water-flooded oil reservoir at Daqing oilfield. Then the efficacies and mechanisms of various concentrations of nitrate in combination with DNB-8 in the inhibition of the activity of SRB enriched culture were compared. Results showed that 1.0 mmol· L^-1 of nitrate or 0. 45 mmol· L^-1 of nitrite inhibited the sulfate-reducing activity of SRB enrichments; the competitive reduction of nitrate by DNB-8 and the nitrite produced were responsible for the suppression. Besides, the SRB enrichment cultures showed a metabolic pathway of dissimilatory nitrate reduction to ammonium （DNRA） via nitrite. The SRB cultures could possibly alleviate the nitrite inhibition by DNRA when they were subjected to high-strength nitrate.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2014年第1期319-326,共8页
Environmental Science
基金
国家自然科学基金项目(31270167)
中国科学院污染生态与环境工程重点实验室项目(2012B)
关键词
硫酸盐还原菌
油藏酸化
硝酸盐还原菌
大庆油田
采出水
sulfate-reducing bacteria
souring of oil reservoir
nitrate-reducing bacteria
Daqing Oilfield
produced water
