Research And Application Of Surfactant Flooding System In Zhuangxi Oil Production Plant

There are 22 units of low permeable reservoirs in Zhuangxi oilproductionplant,includingZhuang52,45,120andso on.Theoiliness areais123.4 km2, producing reserves is 8029×104 t, and recoverable reserves is1572×104t.Theiroilproductionaccountsformorethan45%inZhuangxioilproduction plant. Along with the water injection period, heterogeneity of thereservoirs increases. Producing percent of the reservoirs is heterogeneous,which seriously affects improvement of recover factor. At the same time,becausetwoorthreetimesofprofilecontrolmethodhasbeenusedinmostofthewaterinjectionwells, evenfive toseventimes insomewells, general lowand deep profile control methods play less and less important role. Increaseof oil production is less, period of validity becomes shorter, and benefitbecomes less year-by-year. Soresearchand applicationofsurfactant floodingsysteminZhuangxioilproductionplantwasdeveloped.Throughestablishingactive agent emulsificationspeed, relationofemulsificationspeed,interfacialtension, and flooding rate was researched. The result that the higher theemulsification speed is, the less the interfacial tension of oil and water is hasbeen gained. At the same time emulsification speed is the most importantfactor of flooding rate. Emulsification agent has been developed based onnonyl phenol, and surfactant system for effective flooding has beencomposed. The agent has been used in 3 wells in Zhuang52 block, and goodeffecthasbeengained.Cumulatingoilincreasecomesto5872t.