MOE Key Lab of Coalbed Methane Resources and Reservoiring Process,China University of Mining and Technology Petro China Huabei Oilfield Branch Company China United Coalbed Methane Corporation Limited

针对柿庄北区块煤层注CO2提高甲烷采收率的关键因素及现场工程选区,基于研究区储层特征,结合正交试验设计,开展了影响煤层注CO2提高甲烷采收率的数值模拟研究,评价了注入效果,指出了CO2-ECBM工程选区的储层渗透率门限。结果显示:研究区地质构造简单,顶底板封盖性好,煤层气成藏具有埋深大、煤层厚、含气量高、临界解吸压力高以及渗透率中等偏低、储层压力低的"四高两低"的基本特点;影响研究区注CO2促甲烷增产的关键因素是煤储层渗透率;在较高渗透率煤层注入CO2,有利于提高采收率;较低渗透率煤层可较好地实现CO2封存;要实现柿庄北区块煤层注入CO2显著提高甲烷采收率,储层渗透率应高于0.05×10-3μm2;兼顾提高采收率和CO2的有效埋藏,储层渗透率宜为（0.050.22）×10-3μm2。

according to the key factors of the seam CO 2 iniection in Shihuang North Block toimprove the coalbed methane recovery rate and the site engineering selection.baed on theresevirfeatures of the study block.in combination with the orthogonal experiment design,a numerical simulaton study was conducted on theseam CO _2 injection to improve the coalbed metane recovey rate . The paper evaluated the injecion effct and poited out the resevoir permeatility thveshold of theC_2-ECBM engineeing selected block. The resuts showed tht the geologcal structure of the study block was simple,the sealing of the roof and foor was exceleent.he coalbed nethane reservoir could hav " fou high and twvo low" asic features including th deep depth,tick seam,high gas content and high trtialdesopion pessure as well as the mediun to low permeablity and low reservoir pressure .The key facto afced to the metane production increased efct with the seam Co 2 in ection in the study block vas the permeatiliy of the coal reservoir. A high pemeabiliy seam with the CO 2 ine ction would be favorable to improve the recovery rate.Alow permeability seam could be well o the CO_2 sealed storage. n orderto realize the seam CO_2 injction in Shithuang North block obiously improve the methane recovery rate,the permeablity of thereservoirshould be higherthan 0.05 ×10+/-3)pumn-2. in consideraton to improve the recovery rate and CO 2 efe civeresevoingthe permeability of the reservoir should be( 0.05～0.22)×10~(-3)um~2.

国家自然科学基金资助项目(41302131)；国家科技重大专项资助项目(2011ZX05042-03-01)；中国石油华北油田分公司博士后资助项目(2013E-2208-2015-M08)；