大牛地气田大28井区高产液井合理生产制度研究

Research on reasonable production system of high-liquid well in D28 well block of Daniudi gasfield

针对大28井区盒1气藏液气比高,稳产期短、产量递减快、生产效果差的问题,开展合理生产制度相关研究,改善井区开发效果。研究结果表明:(1)大牛地气田大28井区盒1气藏储层物性差,主要产水类型是天然气成藏过程中驱替不彻底的孔隙残留水,水多数赋存在多套泥质含量较高、物性较差的砂体中;(2)相同物性条件下,初期配产偏高时,生产压差大,产液量高,造成液相伤害,同时积液造成井底回压较大,气井产能不能完全释放,导致开发效果差;(3)为了合理利用地层能量,高产液气井合理生产压差应控制在7 MPa以内,对应的配产比例应低于无阻流量的1/3;(4)高产液井为了获得较高的EUR,取得良好的开发效果,初期压降速率应小于0.025 MPa/d。通过研究制定出合理的生产制度,控制合理生产压差和初期压降速率,高产液井稳产时间明显延长,单井EUR提高40%,为高产液气井的生产管理提供了指导。

Aiming at the problems of high liquid-to-gas ratio,short stable production period,rapid production decline,and poor production effect in the H1 gas reservoir in the D28 well block,relevant research has been carried out,liquid production and reasonable production system to improve the effect of well area development.The research results show that,(1)The reservoir properties of the H1 gas reservoir in the D28 well block of the Daniudi gasfield are poor.The main water production type is the residual water in the pores that is not completely displaced during the natural gas accumulation process.Most of the water is contained in multiple sets of shale content.In sand bodies with higher and poorer physical properties.(2)Under the same physical property conditions,when the initial production allocation is high.A large production pressure difference,causing liquid phase damage,and at the same time,liquid accumulation causes greater bottom hole back pressure and gas wells.The production capacity cannot be fully released,resulting in poor development effects.(3)In order to use formation energy reasonably,the reasonable production pressure difference of high-liquid gas wells should be controlled within 7 MPa,and the corresponding production ratio should be less than 1/3 of the unblocked flow.(4)In order to obtain higher EUR and achieve good development results,the initial pressure drop rate should be less than 0.025 MPa/d.Through research,the mechanism of liquid production have been clarified.A reasonable production system has been formulated,and reasonable production pressure difference and initial pressure drop rate have been controlled.The stable production time of high-liquid wells has been significantly prolonged,and the EUR per well has increased by 40%making high-liquid gas well guidance for production management.