Research on Potential Evaluation of Gas Well Refracturing and Fuzzy Comprehensive Well Selection Method

Abstract

The gas reservoir in the B area is low-permeability sandstone gas reservoir, with complex geological conditions, low permeability and strong heterogeneity and often needed refracturing. While the number of gas wells in the B district was large, leading to difficulty in well selection, and the mining effect of refracturing was affected by many factors, thus it is difficult to conduct quantitative research using conventional methods.Based on the field data in the B area, the potential and fuzzy comprehensive well selection software for gas well refracturing is developed. The paper established the developed potential system of gas reservoir in the B area, calculated recoverable reserves using a type water drive curve, and analyzed potential area by drawing the monthly gas production contour curve,which provided a guiding basis for the decision of refracturing well selection. The fuzzy comprehensive evaluation method was applied to analyze the main factors affecting the refracturing well selection, and the fuzzy comprehensive evaluation model was established to optimize many wells in the B district.Practice results show that the well selection technology based on the combination of the potential area evaluation system and the fuzzy comprehensive evaluation method is reliable, and the refracturing well preferred has obtained good results.