Organization
MOE Key Laboratory of Petroleum Engineering, China University of Petroleum, Beijing 102249, China
Research Institute of Exploration and Development, Tarim Oilfield Company, PetroChina, Korla 841000, China
Petrochemical Plant of Zhongyuan Oilfield Company, SINOPEC, Puyang 457061, China
Abstract
Diffusion in fractured reservoirs, unlike in unfractured reservoirs, is one of the main mechanisms to improve recovery efficiency of matrix. However the mechanism used to be ignored or inadequately understood. In order to study the effect of molecular diffusion on CO2 miscible flooding of fractured reservoir, A multi?鄄phase and multi?鄄component double?鄄medium mathematical model considering molecular diffusion effects is established, derived and solved by finite difference method and Matlab software. The example analysis of a abroad fractured carbonate reservoir is carried out by applying the model established above, the results shows that the established model can accurately simulate the effect of molecular diffusion on CO2 miscible flooding of the fractured reservoir. Compared with the results of Eclipse conventional numerical simulation, it has better applicability and certain comparability. In addition, the effects of molecular diffusion on reserve recovery, interfacial tension and miscible area are comprehensively evaluated. The results show that molecular diffusion can effectively reduce interfacial tension, increase miscible area and enhance oil recovery. The model can provide some help to improve the accuracy of the fractured reservoir dynamic forecasting technology of gas injection.
论文详情