Study On Flooding Effect Of Weak Alkali ASP Compound System In N Oil Area Of A Oilfield

Alkali/surfactant/polymer(ASP)ternary system flooding technology is a new type of oil displacement system based on the advantages of single chemical flooding.The field data of oil displacement operation in the A Oilfield show that single polymer flooding can increase oil recovery by more than 10%compared with water flooding,and ASP flooding can increase oil recovery by more than 20%compared with water flooding.In the current situation of high water cut in oil producing blocks,ASP flooding technology has bright application prospects,which has been vigorously developed and highly valued by various countries.However,the economic consumption of ASP flooding is generally large.Under the current international oil price low environment,how to reduce the cost of oil displacement and strictly control economic consumption is the main reason for the restriction point of popularization and use of ASP flooding technology.Firstly,through literature search and production practice,this paper analyzed the influencing factors of oil displacement effect of ASP system,and formulated Research Countermeasures for each factor.A systematic indoor oil displacement simulation experiment is constructed.Through the oil displacement experiment on the simulated samples,the main and secondary factors of ASP flooding are compared and analyzed,and the function relationship curves of each factor are given.The relationship between injection rate and injection method,interfacial tension,viscosity ratio and reservoir variation coefficient of the main slug of oil displacement capacity of the system are studied emphatically,and the action curves of each factor are drawn,which provides the basis for the flooding scheme of alkalescence ASP flooding in the test area.For the water content of alkalescence ASP flooding in the secondary oil layer of the west block of N area was initially decreased,the questions of low injection pressure and uneven injectivity profile were caused by inefficient and ineffective circulation strips in the test area,profile control was performed on 35 injection Wells with the system of XWT008 and WK.Average injection pressure per well increased by 1.2MPa and apparent inhalation index decreased by 0.15 m~3/(d·m·MPa)after profile control,it can block the high permeable layer.The oil Wells in the test area have seen the effect of stage oil increasing,and the daily increase of oil in 59 oil Wells was 57 tons,and the comprehensive water cut decreased by 0.91 tons.In o rder to further improve the efficiency of tertiary oil recovery and the development benefits,ensure the stable production and the quality,efficiency and sustainable development of ASP fl ooding block,technical support is provided.