Study On Air Foam Flooding Feasibility In Tang80Area Of GanGuYi Oilfield

The Tang80area waterflooding pilot trials began in2001,in the process of waterflooding in wells of east-west fracture water breakthrough,water cut rising fast,indiviual well shut-in for water,north and south to water injection well is hard to work.Oil recovery rate is low,accumulated injection-production ratio is low,formation energy continues to decline,water injection well head pressure continued to rise,water injection pressure close to the crack extension,improve the ability of water injection is difficult.Beside,in shanbei region,this paper combined with drought,there are so many problems,such as large-scale comprehensive water injection development difficulties.In order to improve the development of tang80wellblock speed and improve recovery factor,at the same time in order to give the whole oil field energy,increase the speed of development and to provide experience for recovery,it is necessary to carry out tang80area air injection efficiency of foam flooding pilot test study,to explore the secondary oil recovery of ultra-low permeability oil field to improve oil recovery in this area.By analyzing the reservoir temperature and pressure systems, reservoir sensitivity and fracturing effects of Tang80area, we carried out air flooding, foam flooding, water flooding and other experiments. Evaluated water flooding and foam flooding comprehensive, chose the best foam solution in foam flooding. Clear Tang80area effectively injecting air and foam under16MPa and its effective duration and effective level. Determined the principles of wells optimization of air-bubble flooding and optimize the injection parameters.Field tests showed that foam flooding does not appear injection fluid channeling, each well has efficiency of Liquid increases, precipitation and oil increases, the water drop of original high water cut wells is big, the original low water cut wells is small;and the difference between the moisture content of each well when compared to waterflooding moisture content of each well have significantly reduce. In addition, the economic efficiency significantly, expected input-output ratio is greater than1:3.