In order to maintain the reservoir pressure during secondary oil production large volumes of seawater are injected into reservoirs. This practice introduces high concentrations of sulfate into the reservoir promoting the growth of sulfate-reducing microorganisms (SRM) and results in the production of an increasing volume of produced water (PW) that needs to be discharged. SRM reduce sulfate to sulfide causing reservoir souring and as a mitigation strategy nitrate is injecting along with the seawater into the reservoir. We used PW from the Halfdan oil field (North Sea) to set up microcosms to determine the best reinjection strategy in order to inhibit SRM activity and minimize the environmental impact of PW during secondary oil production. We discuss the effect of temperature, electron donor, and sulfate and nitrate availability on sulfide production and microbial community composition. Temperature and the terminal electron acceptor played a key role in shaping the microbial community of the microcosms. PW reinjection at 62 °C inhibited SRM activity due to nitrite toxicity by encouraging nitrate reduction to nitrite by thermophilic nitrate reducers, while at 74 °C we observed complete absence of any microbial activity over the course of 150 days. KEY POINTS: • Temperature and the presence/ absence of nitrate shaped the microbial community structure. • Thermophilic nitrate reducers convert nitrate to ammonia with the accumulation of nitrite that inhibits sulfide production. • Nitrite inhibition is the most effective nitrate-based souring mitigation mechanisms. • The reinjection of hot produced water to oil reservoirs is a promising souring mitigation approach.

中文翻译：

---

高温油藏硫化物聚集的理化和生物控制[J].

为了在二次采油过程中保持油藏压力，大量海水被注入油藏。这种做法将高浓度的硫酸盐引入储层，促进了硫酸盐还原微生物 (SRM) 的生长，并导致需要排放的采出水 (PW) 的产量不断增加。SRM 将硫酸盐还原为硫化物，导致水库酸化，作为缓解策略，硝酸盐与海水一起注入水库。我们使用来自哈夫丹油田（北海）的 PW 来建立微观世界，以确定最佳回注策略，以抑制 SRM 活动并最大限度地减少二次采油过程中 PW 对环境的影响。我们讨论了温度、电子供体、以及硫酸盐和硝酸盐的可用性对硫化物生产和微生物群落组成的影响。温度和末端电子受体在塑造微观世界的微生物群落中起着关键作用。PW 在 62°C 下回注抑制了 SRM 活性，因为亚硝酸盐毒性通过促进硝酸盐被嗜热硝酸盐还原剂还原为亚硝酸盐，而在 74°C 下，我们观察到在 150 天的过程中完全没有任何微生物活动。要点： • 温度和硝酸盐的存在/不存在塑造了微生物群落结构。• 嗜热硝酸盐还原剂通过亚硝酸盐的积累将硝酸盐转化为氨，从而抑制硫化物的产生。• 亚硝酸盐抑制是最有效的基于硝酸盐的酸化缓解机制。