注蒸汽后期稠油油藏火驱配套工艺矿场试验与认识

为了探索注蒸汽后期稠油油藏转火驱技术的可行性,研制了电加热点火器及配套工具,实现了油层高温点火;通过火线前缘监测、产出气体组分监测和耐高温井下温压监测手段判断燃烧状态、火线前缘位置和推进方向;建立了直井多相管流温度、压力分布模型,确定了火驱生产制度和生产方式,研制了配套防气工具,形成火驱举升工艺;根据火驱不同生产阶段,注气井和生产井腐蚀特征,模拟井下工况开展了室内氧腐蚀和酸性气体腐蚀试验,掌握了管材腐蚀特征,确定了注气井、生产井的防腐工艺。现场试验表明,该技术能满足火驱生产需求,也证实了注蒸汽后的稠油油藏转火驱的可行性,为同类油藏转火驱技术提供了技术支持。

Field test and understanding of fireflooding matching technology in heavy oil reservoir in later stage of steam injection

In order to explore the feasibility of fire flooding technology for heavy oil in later stage of steam injection, an electrically heated igniter and auxiliary tools have been developed and ignition of oil reservoir at high temperature is realized; the combustion regime, live wire front location and advancing direction were judged through monitoring of live wire front, monitoring of components of produced gas and pressure-resistant down-hole temperature and pressure detection means; a multi-phase string flow temperature and pressure distribution model was built for vertical wells, fire flood working system and production fashion were determined, and auxiliary gas-proof tools were developed and the fire flooding and lift technology was created. According to various production stages by fire flooding and corrosion features of gas injector and producer, down-hole working conditions were simulated and indoor corrosion tests were carried out for oxygen corrosion and acidic gas corrosion, the tubular corrosion features were understood and the corrosion-proof technology was defined for gas injector and producer. Field tests show that this technology can meet the production requirement by fire flooding, and also proved the feasibility of converting to fire flooding of heavy oil reservoir in later stage of steam injection, providing technical support for similar reservoirs converting to fire flooding technology.