Improved Gas Recovery from Wells with Wellbore Damage

• Main Authors: Yen-fu Lin, 林彥甫
• Other Authors: Zsay-shing Lin
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/14429796463255992577

碩士 === 國立成功大學 === 資源工程學系碩博士班 === 97 === The formation damage is the major reason to cause low productivity in a producing well. The formation damage can be estimated by the skin factor which could be removed by acidizing treatment. The purpose of this study is to estimate skin factor from pressure test data of the wells and to study the improved gas recovery of low productivity wells after acidizing treatment for the C gas reservoir in Taiwan. The major works in this study include: (1) using the conventional analysis method to analyze pressure test data of testing wells and to estimate permabilities and skin factors; (2) choosing the candidate wells among the wells analyzed by R-factor method; (3) conducting a numerical model of C gas reservoir matching the field data and simulated data of pressure and water production; (4) predicting the improved gas recovery of the candidate wells after acidizing treatment. Based on the results from this study, four wells were chosen for analyzing pressure data to obtain permeabilities and skins. The R-factors estimated for C-110S, C-126S, C-127L and C-112(L&S) were 0.86, 0.90, 0.84, and 0.83, respectively. The improved gas reserve of four candidate wells after acidizing treatment is 2.46×1011 (SCF), 1.20×1011(SCF), 0.85×1011 (SCF) and 0.15×1010 (SCF), respectively. The results showed that the wells of C-110S, C-126S and C-127L can be acidized to achieve the purpose of improved gas recovery; C-112(L&S) well is not.