Study On Seepage Mechanism And Development Of Technology For Super Heavy Oil In Wangzhuang Oilfield

Wang Zhuang oilfield is a typical super heavy oil reservoir. It is very difficult for thegeneral development and vertical well steam injection development. There is no successfuldevelopment experiences in China and abroad. In this paper, physical simulation andnumerical simulation method have been carried out for the research of super heavy oilreservoir development technology through the indoor experiment and obtained the followingresearch results and understanding:The crude oil of Wang Zhuang oilfield is super heavy oil and the seepage characteristicdoes not conform to Darcy’s law. The super heavy oil shows the characteristics of nonNewton fluid through the study on crude oil rheology experiment laboratory. But whenincrease of temperature, It will fall finally into a Newton fluid.The indoor experimental study on single-phase flow for Wang Zhuang oil field superheavy oil shows that the seepage of super heavy oil, the existence of starting pressuregradient initial. The seepage by crude oil viscosity and formation temperature. The crude oilviscosity of super heavy oil is very sensitive to temperature, viscosity reduce with theincrease of temperature.Established the Wang Zhuang oilfield dimensional scaled physical model under highpressure and high temperature, and studied the different development stages of horizontalwell steam flooding mechanism. Research shows that steam flooding the entire process isdivided into three stages: water extraction stage, steam drive, steam breakthrough period.Horizontal wells bottomhole dryness steam flooding, steam injection strength have a greateffect for the horizontal well steam flooding.Establish the concept of horizontal well group model of one-injection-well andone-production-well in Wang Zhuang oil, simulation of different oil reservoirs with differentpermeability, the horizontal well steam flooding development effect. Research thinks, keygeological factors of horizontal well steam flooding is mainly has: the reservoir permeability,oil saturation and formation dip. Research shows that, the reservoir permeability, oilsaturation is higher, the steam flooding development effect is better; dip angle is more big,steam flooding development effect is more poor, the local layer angle greater than5degrees,is not conducive to horizontal well steam flooding.Through the numerical simulation, the development technical policy of the reasonablewell spacing, reservoir thickness, oil viscosity, bottom hole steam, steam injection rate is been researched. Reasonable well pattern of horizontal well steam flooding is the nine pointto five point method; with the thickness increasing, the reasonable well spacing is small; theviscosity of crude oil is more big, the reasonable well spacing is small. The reasonable wellspacing is different in different reservoir types. The more viscous crude well spacing is small,super heavy oil well is the smallest; crude oil more thick, reservoir thickness is bigger;bottom hole steam, steam injection velocity, horizontal well steam flooding developmenteffect is better, should not be less than0.4of the dry bottom hole steam steam flooding.Research on Wang Zhuang oilfield in different reservoir conditions HDCS developmenttechnology limit optimization.Through the limit thickness, reasonable well distance, vertical position, horizontalsection length, injection parameters and a series of technical limit optimization research,established the Wang Zhuang oilfield reservoir selection principle of HDCS technology.Maded the horizontal well steam flooding test plan of Zheng411block in Wang Zhuangoilfield, Forecasted the development indexes. The horizontal well steam flooding technologycan improve the recovery rate of20.46%by HDCS technology.