Research On Injection Technology In Mu 146 Experiment Block Of Nitrogen Foam Flooding

As the 39 years’ development of water flooding in Mu 146,it has stepped into the period of “ high produced fluid,high water cut,high recovery degree”.It has the characteristics of serious in-layer heterogeneity,big difference in water intaking between layers,so water channeling takes place easily through high permeability channels.Thus,high water ratio,low efficiency of water injection,serious phenomenon of invalid circulation and low efficiency of water flooding,causing the improvment of lower permeability reservior’s producing degree of reserves and it has the difficulty in improving production of low permeability reservior by water flooding.Jilin oilfield Company start nitrogen foam flooding experiment to enhance oil recovery in Xin mu 146 Block in 2015.Taking the advantage of excellent ability of nitrogen foam injection,remaining oil in the small pores and nitrogen foam flooding effect,the influnce of heterogeneity is brought down and swept volume is expanded as well as the producing energy is complemented,which fully utilize the lower permibility reservior production.Nitrogen Foam flooding technology parameters is easily influnced by oil deposit conditions,targeted design is needed according to the characrastics of oil deposit.This essay evaluates the foam system of nitrogen foam flooding in Mu 146 block and establishes the way of screening and evaluation of foam system.Furtherly,foam system perfomance between normal condition and high temperature and high pressure condition is compared and screened,in which the different influence factors of foam system is analyzed generally.In addition,the design of low cost injection technology of nitrogen foam flooding is optimized,in which the special requiment of changing injection medium frequently is considered.Furthermore,optimization of the wellhead pressure levels,anti-corrosion levels,pipeline combinations and steel grade of injection well is demonstrated.Thus,targetedly designed injection way of experiment block and injection allocation technology of profile control is fulfilled,the design of packer and pluged seal tubing nipple is optimized and technology of gas channeling prevention is reserved.Moreover,the application effect of this technology through different angles,like technology design,construction order,safety and enviroment protection,field application is evaluated.And 4 foam systems that meet the demand of experiment block requirment is finally screened and a technology system with low cost is designed and formed.The application of injection is successful in the experiment block which shows the feasibility of nitrogen foam flooding.