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CO_2注入煤层中能提高煤层气回收率,理论上说可达到本煤层煤层气的100％。美国新墨西哥州圣胡安煤田首次多井示范性试验方式的最初结果表明,CO_2提高煤层气回收率(CO_2-ECBM)在技术上是可行的。通过重新完井和清水钻孔,在仍保持2.5Bcf/天的产气量后,圣胡安煤田的许多煤层气经营者面临近期产量明显下降,采用ECBM可能缓和煤层气的产量。水果组煤储层的筛选很有利于采用ECBM技术:断层少和储层分成隔区,横向延续和透气性的煤层,和集中的煤层几何形状。水果组煤田已钻有大量的煤层气井,采用CO_2注入器重新完井可降低费用。壳牌公司的Cortez CO_2管道为世界上最大的管道,能按照自己的路线直接通过圣胡安煤田到达二叠纪油田,供提高石油回收率方法的CO_2淹灌。提高煤层气回收率的方法能提高同一气井的气体回收率。这样就会有更多的产量符合美国第29条款的税收优惠政策。通过保持储层的压力,提高煤层气回收的方法也能降低加压的费用。根据所用的CO_2/CH_4比率,提高煤层气回收率的方法按目前的井口煤层气销售价来说,是经济的。适合采用ECBM方法的项目都可能从目前美国国会正在考虑的CO_2分离优惠政策中获利。一天1Bcf至2Bcf CO_2提供给圣胡安煤田,估计能使煤层气储量增加5至10Tcf,再加上在这富饶的煤田已注册登记的13Tcf煤层气。美国具有潜在使用这种提高煤层气回收率方法的其他煤田,包括尤困塔(Uinta)煤田,拉顿(Raton)煤田,波德河煤田,勇士煤田和阿帕拉契煤田。
The injection of CO2 into the coal seam can improve the CBM recovery rate, theoretically it can reach 100% of the CBM in this coal seam. The initial results of the first multi-well demonstration test in the San Juan Coalfield, New Mexico, USA, show that it is technically feasible to increase the recovery of CO 2 -ECBM with CO 2. Many CBM operators in the San Juan coal field have experienced a sharp drop in recent production after re- completion and clean water drilling while still maintaining a gas production of 2.5 Bcf / day, and the use of ECBM may ease the production of CBM. The screening of fruit group coal reservoirs favors the use of ECBM technology: seams with few faults and subdivided reservoirs, laterally continuous and gas-permeable seams, and concentrated coal seam geometries. A large number of coalbed methane wells have been drilled in the fruit group coalfield, and the CO_2 injector can be used again to reduce costs. Shell’s Cortez CO 2 pipeline, the largest pipeline in the world, can route its own route directly to the Permian oil fields through the San Juan coal field for flooding CO 2 to increase oil recovery rates. Methods to increase CBM recovery can increase gas recovery in the same gas well. As a result, more output will be eligible for tax breaks under Article 29 of the U.S. By keeping the pressure in the reservoir, the way to increase CBM recovery can also reduce the cost of pressurization. Depending on the CO 2 / CH 4 ratio used, the method for increasing CBM recovery is economical, given the current sales price of wellhead CBM. Projects suitable for adoption of the ECBM approach may benefit from the preferential CO 2 sequestration currently being considered by the U.S. Congress. One day from 1Bcf to 2Bcf CO_2 to the San Juan Coalfield is estimated to increase CBM reserves by 5 to 10Tcf, plus 13Tcf CBM already registered in this fertile coalfield. Other coalfields in the United States that have the potential to use this method of increasing CBM recovery rates include the Uinta, Raton, Pod River, Warriors and Appalachian fields.