Study On Technical Countermeasures Of Cyclic Steam Stimulation Converting Into Chemical Viscosity-reducing Compound Flooding In Heavy Oil

In the later period of cyclic steam stimulation,the formation temperature rises,the pressure decreases,and the dependence on heat is reduced.Therefore,the addition of formation energy on the basis of viscosity reduction should have a better effect.As a new type of complex flooding method for heavy oil development,chemical viscosity-reducing compound flooding not only has the oil displacement mechanism of polymer and viscosity reducer,but also has synergistic effects.Therefore,it is necessary to clarify the recovery mechanism of chemical viscosity-reducing compound flooding after cyclic steam stimulation,optimize technical countermeasures,and further improve the development system of transfer flooding after thermal recovery of heavy oil.In this paper,numerical simulation technology is used to study the mechanical models of typical well groups in the actual block as the research object.Aiming at the problem of poor development effectiveness after high rounds of heavy oil cyclic steam stimulation,the adaptability research of cyclic steam stimulation converting into chemical viscosity-reducing compound flooding is carried out,and the main influencing factors of heavy oil cyclic steam stimulation converting into chemical viscosity-reducing compound flooding were analyzed.For a certain block of Shengli Oilfield,by studying the development status of the target block and the remaining oil distribution,the chemical viscosity-reducing compound flooding is determined as the transfer flooding method after cyclic steam stimulation,and the optimal injection method and appropriate injection and production parameters are determined through numerical simulation,which provides technical support for the field implementation of heavy oil steam stimulation to chemical viscosity reduction compound flooding.