Study And Application Of Carbon Dioxide Slug Assisting Fracture Technology On Zhuang 74 Block

Since the domestic oilfield has been in high water cut stage, traditional stimulations of well such as acid treating, fracture and broken down which have increased the oil production, still have some problems as follow: low increase production, short useful life , little range of application, new oil reservoir damage, imperfect oil well re-treatment, more complex stemming component and imperfect broken down and fracture treatment effect. In a word, study of carbon dioxide slug assisting fracture technology is very important.Zhuang 74 block is an ultra-low permeable reservoir. Fracturing and re-treatment are the main increase production means. During the early stage, the treatment has acquired some effect, but with the formation energy decrease and other reasons, such as not flowing back carrier fluids on time, the final effect was very bad. In order to improve the production of Zhuang 74 block, hydraulic fracture with carbon dioxide injection are combined together to reduce these negative effect. Injecting liquid CO2 as pad fluid can expand the contact area with reservoir oil, which makes better miscible effect, and assisting production after fracture and increase oil production can come into being.In this paper, the combination technology of hydraulic fracture and carbon dioxide injection have been studied to increase oil production. Design the experiment about how to ascertain minimal miscibility pressure of the carbon dioxide throughput and bring the experimental study into operation, and the same is to carbon dioxide assisting hydraulic fracture experimental study.After studying and analyzing the optimization method of hydraulic fracture, the optimization method of carbon dioxide slug assisting fracture was designed and the numerical stimulation was conducted. Finally, the economic of this techonlogy was evaluated.