一种高效复合除硫剂性能评价及现场试验

Performance Evaluation and Field Test of an Efficient Compound Sulfur Removal Agent

针对大牛地奥陶系风化壳气藏低含硫气井采用现用井筒除硫工艺导致采气管线结垢严重及除硫成本高的问题,研发了一种高效复合三嗪除硫剂,评价了其硫容、缓蚀阻垢及配伍性能。室内评价结果显示,质量分数5%的高效复合除硫剂硫容为14.04~14.56g/L,在高压及高温条件下,Q235钢材在复合除硫剂溶液中平均静态腐蚀速率为0.0012mm/a、平均动态腐蚀速率为0.1223mm/a,低于国家腐蚀标准,同时静态缓蚀率达46.0%、动态缓蚀率达50.4%,阻垢率达82.4%,其除硫及缓蚀阻垢性能佳且与现用药剂、地层水配伍性良好。优选2口低含硫气井(H_(2)S体积分数为90.3×10^(-6)~260.4×10^(-6))开展了现场试验,现场应用结果表明,该高效复合除硫剂能将优选井的硫化氢体积分数降至0,与现用除硫剂相比,除硫能力提高489%,除硫成本降低28.8%。因此,该高效复合除硫剂在大牛地奥陶系风化壳气藏具有广阔的推广应用前景。

In order to solve the problems of serious scaling in gas production pipeline and high cost of sulfur removal caused by the wellhole desulfurization technology in the low sulfur gas wells of the Daniudi Ordovician weathering crust gas reservoirs,an efficient compound triazine sulfur removal agent was developed.And its sulfur capacity,corrosion and scale inhibition and compatibility were evaluated.Laboratory experiment results show that the sulfur capacity of the efficient compound sulfur removal agent with 5%of mass fraction is 14.04-14.56g/L,average static and dynamic corrosion rate of steel Q235 in the solution of compound sulfur removal agent at high pressure and temperature is 0.0012mm/a and 0.1223mm/a respectively being lower than national corrosion standard,and the static and dynamic sustained release rate is 46.0% and 50.4%respectively,and the scale inhibition rate is 82.4%.It has strong capacity of sulfur removal,corrosion and scale inhibition,and has good compatibility with formation water and other agents.Two gas wells with volume fraction of H_(2)S of 90.3×10^(-6)-260.4×10^(-6)were selected for field test.The application shows that this efficient compound sulfur removal agent can reduce the volume fraction of hydrogen sulfide to 0 in two gas wells.Compared with the current desulfurization agent,its desulfurization capacity increased by 489%and its cost of desulfurization reduced by 28.8%.Therefore,this efficient compound sulfur removal agent has a broad application prospect in Daniudi Ordovician weathering crust gas reservoirs.