玛湖致密油开发硫化氢产生原因

玛湖油田三叠系百口泉组油藏致密油开发过程中，62%的油井产硫化氢。为明确硫化氢产生原因，分别采用硫化氢定性评价和定量测定方法开展了微生物硫酸盐还原和酸岩反应生成硫化氢的研究。实验结果表明，在50℃或含杀菌剂条件下，硫酸盐还原菌不生长也不产生硫化氢；玛湖百口泉组油藏50.0 g岩芯粉与15%的盐酸完全反应可生成4.34×10^-6 mol硫化氢。因此，储层矿物中酸挥发性硫化物与盐酸反应是玛湖油田百口泉组油藏致密油开发过程中硫化氢产生的根本原因。该研究结果为预防硫化氢产生和保障玛湖安全生产提供了重要技术支撑。

Mechanism of Hydrogen Sulfide Generation During Tight Oil Development at Mahu

In the development of tight oil in the Triassic Baikouquan Formation of Mahu Oilfield, hydrogen sulfide has been detected in 62 percent of production wells. In order to find out the cause of the generation of hydrogen sulfide, qualitative evaluation and quantitative analysis experiments have been applied to investigate the hydrogen sulfide generation by bacterial sulfate reduction and acid-rock reaction individually at reservoir condition. The results show that sulfate-reducing bacteria cannot multiply and produce hydrogen sulfide at 50℃ or in presence of bactericide. 4.34×10^-6 mol hydrogen sulfide are produced by the reaction of the 50.0 g of core powder with 15% hydrochloric acid. The primary cause of hydrogen sulfide generation is the reaction of hydrochloric acid and the acid volatile sulfide in the reservoir. The research results provide an important technical support for preventing generation of hydrogen sulfide and for maintaining the safety production of Mahu tight oil.