Experiment Study On Polymer Flooding Technology In Xi5-16 Block Of Fuyu Oilfield

There are some new problems with Fu-Yu oil field after three development regulation, such as small well spacing, complicated and sensible injection-production relationship, great aeolotropism during layer and interlamination, the development of the fracture and pore path, highly ditraction of the remaining oil and increcing of the underground oil viscosity, which leads to the decrecing of the conformance efficiency, bad displacement effect, high speed of the water cut of the new well, serious non-effective water circulation, which indicates that Fu-Yu oil field is to enter the high water cut and high degree of reserve recovery phase, and chemical flood is sure to be done. Aiming at meeting the practical demand of the Fuyu Xi5-16 oilfield, with the means of the instrumental analysis,physics modeling and the reservoir engineering theory ,the author launched the study on compound-polymer selection,technical effect evaluation,molecular coil dimension,flow property,flooding efficiency and oil displacement efficienc。The results shows that the minimum core permeability which adapted to the"Gaofen"polymer is 40×10^-3um², adapted to"Chaogao"polymer is 60×10^-3um²,adapted to"Kangyan"polymer is 70×10^-3um²ã€‚the minimum core permeability which adapted to the"Chaogao"polymer is 70×10^-3um² when the content of the"Chaogao"polymer in the compound-polymer comes to 60%. Comparing with the common polymer, compound-polymer gets the charateristic such as high salt-reisiting and cut-resisiting, wide distribution of the molecular coil dimension, small unreached pore volume, high displacement dffeciency. The higher polymer solution viscosity is, the bigger stug size is, the earlier injection time is, the better polymer flooding increse oil. Comparing with the chromium polymer gel, high molecular weight polymer silution`s profile control efficiency is good, the compatibility with the polymer silution is good, the accommondation with the common reservoir environment is good; in view of the situation of the big fracture and big channel of the fissured reseivoir, we recommend the swellable particles as the profile control silution.Suggest Fuyuoilfield polymer flooding slug:0.04PV Front slug(compound-polymer,Cp=1600 mg/L)+0.3PV main slug(compound-polymer,Cp=1300 mg/L)+0.04PV protect slug(compound-polymer,Cp=1000 mg/L)。And,compound-polymer proportionKangyan: Chaogao:Gaofen=25:60:15...