Analysis And Research On Inefficient Reason And Treatment Technology Of Water Injection In Dujiatai Reservoir

Dujiatai reservoir is a typical low permeability reservoir in Liaohe oil field.Its oil area is 37.2 km2 and geological reserves are 2409×104t.This reservoir has the characteristics of low permeability,small fault block,thin interblended layers,water and velocity sensitivity,narrow part in the river,the connected heterogeneity,few fractures,less pressure drop and so on.After natural energy development,the reservoir has implemented water injection development for many years.But due to no complete set of the injection technology,wells in succession stop because of not injecting,and oil field meets serious technical bottleneck in effective development,at last reservoir recovery rate is only 11.8%.How to effectively develop low permeability field and difficult employment reserves puts on the agenda.This article establish the water injection technology boundaries,design the reasonable injection-production patterns and the parameters,and form the irregular area of water injection mode which is relative with the sedimentary faces by flooding mechanism and reservoir sensitivity study on the DuJiatai reservoir.The article studies a fine processing sewage system which considers the membrane filtration as the core,and make dissolved gas floating and multilevel filtering and other preprocessing technologies for the security.Besides it devises the deep treatment of sewage system,of which termite filtration technology for film is the key,to guarantee the injection water quality achieved respectively A1,B1 level standard.At the same time it solves the difficult problem of particles migration jam through pore space.By using stimulate technology which includes application of the high pressure and multilevel stimulate,as well as broken down、antis welling、antiseptic and ant scale method on the first stage.Meanwhile it promote test about decreased pressure and stimulate of water well,and achieve the formation deep processing by composite acid and retarding.Besides it suppresses second precipitation production with cooperation.By the hydraulic fracturing,we may improve the inefficient infectivity.