摘要
随着大牛地气田全面进入二次增压中后期,且气藏类型也逐渐扩展为上古、下古及煤层气三类气藏,气井产气、产液及压力递减规律等发生变化,导致天然气水合物生成的影响因素也发生变化。利用PIPESIM软件对气井水合物生成的影响因素进行单因素敏感性分析,明确天然气水合物生成的主控因素,并预测气井水合物生成位置及注醇量,以此为依据进行注醇制度调整。研究结果表明,上古气藏影响水合物生成的主要因素为进站压力、矿化度、环境温度;煤层气气藏影响水合物生成的主要因素为矿化度、产液量、环境温度、进站压力;下古气藏影响水合物生成的主要因素为矿化度、环境温度、进站压力、产液量。以气井进站压力、环境温度和产液量作为理论注醇量主要决定因素,进行理论注醇量模拟,得出分藏理论注醇指导表,三个气藏注醇量大小排序为上古>煤层气>下古。
As the Daniudi Gas Field has entered the middle and late stages of secondary pressurization,thetypes of gas reservoirs have gradually expanded to include three categories;Upper Paleozoic,Lower Paleozoic,and coal-bed methane.Consequently,the gas production,liquid production,and pressure decline patterns of gaswells have changed,leading to variations in the factors affecting natural gas hydrate formation.The PIPESIMsoftware is applied to analyze the univariate sensitivity of these factors,clarify the main controlling factors ofnatural gas hydrate formation,and predict the formation location and methanol injection for gas well hydrates.Based on this analysis,the methanol injection system is adjusted.The research results indicate that inlet pres-sure,salinity,and ambient temperature are the primary factors affecting hydrate formation in Upper Paleozoicgas reservoirs;salinity,liquid production,ambient temperature,and inlet pressure are the main influencing fac-tors in coal-bed methane reservoirs;salinity,ambient temperature,inlet pressure,and liquid production are thekey factors in Lower Paleozoic gas reservoirs.The theoretical methanol injection is stimulated using inlet pres-sure,ambient temperature,and liquid production as the main determining factors to develop a methanol injec-tion guidance table for each reservoir.The ranking of methanol injection in the three gas reservoirs is UpperPaleozoic>coal-bed methane>Lower Paleozoic.
作者
杨秀磊
Yang Xiulei(No.1 Gas Production Plant,SINOPEC North China Oil&Gas Company,Zhengahou Henan 450006)
出处
《中外能源》
2025年第5期54-59,共6页
Sino-Global Energy
关键词
天然气水合物
二次增压
主控因素
敏感性分析
注醇量
大牛地气田
natural gas hydrate
secondary pressurization
main controlling factors
sensitivity analysis
methanolinjection
Daniu Gas Field
