Study Of Alternate Injection Of Foam And AS System In EOR After Polymer Flooding

Polymer flooding technology has been developing rapidly in china. For instance, greatadvancement has been achieved with polymer flooding after water flooding to enhance oilrecovery in Daqing oil-field and the test scale has been changed from pilot test toindustri-alized application.However,there is still about 40-50% remaining oil kept in oil-beari-ng formation after polymer flooding, and how to further enhance recovery factor afterpolymer flooding has become the focus of research at present. Several measures such asmicrobial flooding, alkali-surfactant-polymer flooding and micro gel flooding and foamflooding are presented to further enhance recovery factor according to the characteristics ofresidual oil distribution being highly scattered after polymer flooding and in combination withthe laboratory experiment and field pilot results.The incremental oil recovery increased by 10% with ASP flooding more than withpolymer flooding. Foam combined flooding is a new EOR technique which was developed onthe basis of alkaline-surfactant-polymer combined flooding method.Experiment result showsthat the displacement efficiency of foam flooding by 20% higher than that of polymerflooding. The microbial enhanced oil recovery(MEOR) can be principally divided into twoclasses according to the microorganisms used:oxogenous,screened in the laboratory orindigenous,present in the reservoir strata. The physical simulation of core displacement testshow that oil recovery can be improved 5% by using MEOR after polymer flooding.Preferably effect of ASP flooding and foam flooding,but the cost clear high, apply get limit.And that intricate technic and immature craft of MEOR, application encounter difficulty.Aim at an above circumstance, this literary grace used the AS system and foam to infuseinto alternately of method, carried on physics to imitate a research.The AS system differentfrom the foam system in using surfactant, enhance the function of two systems.The surfactantin the AS system is mainly used for becoming superlower interface tension and enhancing theflooding efficiency, but the surfactant in the foam mainly used for becoming a higher foamof the FCI value and sealing to block up high osmosis passage and flows controlling.Bymeans of the work of sieving,optimizing dispensation and the physical emulation offlooding oil experiment etc.Analysed the experiment results of surfactant.Deepen theknowledge of EOR, carried on a beneficial study of furthering the development of EORtechnique.