摘要
针对柿庄北区块煤层注CO_2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CO_2提高甲烷采收率的数值模拟研究,评价了注入效果,指出了CO_2-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CO_2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CO_2,有利于提高采收率;较低渗透率煤层可较好地实现CO_2封存;要实现柿庄北区块煤层注入CO_2显著提高甲烷采收率,储层渗透率应高于0.05×10^(-3)μm^2;兼顾提高采收率和CO_2的有效埋藏,储层渗透率宜为(0.05~0.22)×10^(-3)μm^2。
According to the key factors of the seam CO2 injection in Shizhuang North Block to improve the coalbed methane recovery rate and the site engineering selection,based on the reservoir features of the study block,in combination with the orthogonal experiment design,a numerical simulation study was conducted on the seam CO2 injection to improve the coalbed methane recovery rate. The paper evaluated the injection effect and pointed out the reservoir permeability threshold of the CO2- ECBM engineering selected block. The results showed that the geological structure of the study block was simple,the sealing of the roof and floor was excellent,the coalbed methane reservoir could have ＂ four high and two low＂ basic features,including the deep depth,thick seam,high gas content and high critical desorption pressure as well as the medium to low permeability and low reservoir pressure. The key factor affected to the methane production increased effect with the seam CO2 injection in the study block was the permeability of the coal reservoir. A high permeability seam with the CO2 injection would be favorable to improve the recovery rate. A low permeability seam could be well to the CO2 sealed storage. In order to realize the seam CO2 injection in Shizhuang North block obviously improve the methane recovery rate,the permeability of the reservoir should be higher than 0. 05 × 10^-3μm^2. In consideration to improve the recovery rate and CO2 effective reservoiring,the permeability of the reservoir should be（ 0. 05 - 0. 22） × 10^-3μm^2.
出处
《煤炭科学技术》
CAS
北大核心
2016年第6期205-210,共6页
Coal Science and Technology
基金
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)
关键词
煤层气
CO2注入
采收率
CO2封存
coalbed methane
CO2 injection
recovery rate
CO2 sealed storage
