Grey Correlation Analysis-based Selection Method of Fracturing Well and Formation for Polymer Flooding

摘要

Fracturing production wells is an important stimulation measure in the process of polymer flooding; reasonable application of this measure can increase oil production and improve the polymer flooding recovery. By regarding the polymer flooding wells a grey system, grey correlation analysis is performed to analyze the influences of various factors on polymer flooding effect, and the primary factors affecting the selection of fracturing well for polymer flooding are identified. Based on fracturing effects of thirteen polymer flooding wells, seven factors, such as pre-fracture skin factor, permeability, are chosen as the influencing factors. Based on the analysis, the descending order of the factors by their influences on fracturing effect is: skin factor, permeability, water cut, formation thickness, formation pressure, mobility, and oil production. Based the relations between the main controlling factors and fracturing effect, a conceptual model is established as the selection method of fracturing well. It is validated that the predicting accuracy of the model can reach 90%. Combining geological research and dynamic analysis, the selection standards are further improved to provide a basis for the selection of fracturing well and formation for polymer flooding.