The Research On Mechanism And Adaptability Of Deep Profile/Displacement System In The Conglomerate Oil Reservoir

kelamayi oilfield which is one of the oldest and largest oilfields in our coutry, plays an important role indomestic oil and gas production. With the development of the oilfiled, old blocks are producing at ahigh-water cut stage. At present, comprehensive water cut of the old blocks has reached to70%above,even water cut of many blocks has arrived at90%. So, it is more and more necessary for oil workers totap the remaining oil in older oilfields, enhance the oil recovery and prolong stable oil production period bydeep profile/displacement technology in tertiary oil recovery. Based on geological characteristics and fluidproperty of kelamayi oilfield, the modern reservoir engineering, oil chemical, enhancing oil recovery andmodern testing technology theory which are taken as the guide, instrumental analysis and physicalsimulation experiments have been carried out to study performance evaluation of the Cr³⁺polymer gel andresearch mechanism and adaptability of deep profile/displacement system in the conglomerate oil reservoir.The results show that when the permeability of cores is higher and the concentration of polymer andcrosslinking agent is less, the resistance factor and residual resistance factor of fluid diverting agent aresmaller. In addition, the resistance factor of "Chacheng" polymer,"Chacheng" polymer gel and "Gaofen"polymer gel is larger than the residual resistance factor, showing the unique seepage property. Besides, withthe same average permeability of the model and injection slug size of the fluid diverting agent,"agent1" ismore adaptive to the model whose permeability variation coefficient is0.59,"agent2" can match betterwith the model with permeability variation coefficient is0.72and "agent3" is fitter for the model withpermeability variation coefficient is0.89. What's more, under the conditions that permeability variationcoefficient of the model and injection slug size are the same,"agent1" is more adaptive to the model whoseaverage permeability is450×10-3μm2,"agent2" can match better with the model with average permeabilityis900×10-3μm2and "agent3" is fitter for the model with average permeability is1800×10-3μm2. Thus, withthe same average permeability and permeability variation coefficient of the model, the more the fluiddiverting agent is used, the higher the injection pressure is and so is the recovery.