The Research Of The Carbon Dioxide Complicated Huff And Puff Technology Of DU 813 Exploratory Areas

Liao He oil field is the biggest production base of heavy and super heavy oil in china. The annual output of heavy and supper oil is 70 percentage of the crude oil. The super heavy oil plays an important role in all products. One of the most important exploitation technologies is cyclic steam stimulation. In the late middle period of exploring, the formation pressure decreases obviously and the properties of reserved oil has changed. Meanwhile, the saturation distributed near the well has also decreased and the groundwater has increased. As result, it turns to be more and more difficult to explore the oil and the effect of cyclic steam stimulation turns to be worse and worse. So the water recovery period of oil well became longer and the ratio of oil and gas becomes lower, even it may below economic limited line. It is harm to the sustainable development of the oil field. Aiming at the worse of the stimulation and effect of exploring in the late middle period, a new technological process that is named"CO₂+ Surfactant + vapor three compound cyclic steam stimulation"method has been put forward. It has formed a certain scale, and the effect is obviously. But the theoretical research is few yet. So it is important to study the mechanism of the yield of oil in order to guide the construction and improved the effeteness further.DU 813 exploratory areas is as an example in this paper. In order to research the problems during the late middle period of exploring of the reserved super heavy oil, a physical experiment is used for simulation. The key factors which are affecting the method have been found. A numeric simulation is given combined with the properties of the reserved oil. The predictions with the heating efficiency of vapor and CO₂ to the oil, period production and economic benefit are also given. The optimal technique parameters such as the infection method, the amount of infection and the later production are given to improve the effeteness of CO₂ compound cyclic steam stimulation method. The theory of"CO₂+ Surfactant + vapor three compound cyclic steam stimulation"method has formed through to the research. It provides a theoretical basis and technical support for large scale popularizing the technique to the heavy and supper heavy oil field.