Research And Application Of Steam Injection Diversification Technology On Qi-40 Block Steam Flooding

The steam flooding reservoir,Qi 40 Block is located in the Huan Shu updip-stairs area,Qi-40 Steam flooding block is located in the steps in updip of Huanshu,its development objective layer is lotus reservoir,which is located in the western depression of Liaohe rift south section of the western slope in Huanxiling oilfield on structure.The reservoir is a typical deep interbedded heavy oil reservoir.It surrounded by fault sealing,composing of monoclinic structure in North West to South East tilt.With dip angle 4-25 °,oil bearing area 7.9km2,original geological reserves of 3721×104t,buried depth of-625?-1050m,average density of crude oil reservoir 0.9686g/m3,ground degassed crude viscosity 2639mPa.s(50?),freezing point-7?13 ?,sulfur content of 0.29%,wax content of 5.8%,colloid and asphalting content of 32.7%.The qi-40 block is developed by cyclic steam stimulation in the year of 1987,then 4 well groups of steam flooding pilot test carried on in the year of 1998,entered the implementation phase of steam flooding industrialization when it has 150 well groups in 2006.Block daily oil level increased from 1280t(initial)to 193 1t(highest)after the block switching to steam flooding totally,and realized the continuous rise of sixth hundreds of tons level.At present,qi-40 block has 83 well groups,60%of the total.the industrialization well groups are gradually into the flooding stage or breakthrough stage with the continuously deepening production.Contradict among reservoir interlayer and planes is increasing.The steam single unidirectional way phenomenon is serious.The phenomenon between injection and production wells and oil wells of high temperature steam channeling is serious.No steam injection wells dynamic deployment,a sharp decline in output,more gas injection less oil and so on after entering the flooding stage.Those are seriously affect the development effect and economic benefit on steam flooding project.This paper is analyzing the main problems of the steam flooding development according to process conditions and the scene production data of qi-40 block based on dynamic production about steam flooding wells.It develops a test on steam air and nitrogen injection auxiliary drive,develops a set of technology,which suitable for steam flooding diversified steam injection in Qi-40 block.The technology effectively improves the plane and vertical producing degree of reservoir,and improves the development result of steam flooding.Through studying the technology of numerical simulation and scene tests,eccentric layered steam to drive the steam injection,the technology of heat insulation casing completion separate steam injection,the technology of separate steam injection concentric tube,well turned,steam injection wells in high dose profile,product wells mechanical sealing channeling,the technology of steam steering and so on.