克拉2气田排水采气工艺优选及效果分析

克拉2气田作为西气东输的主力气田，因地质原因部分气井已经出水，严重影响气井产能和最终采收率，亟需采取排水采气工艺措施以维持气井稳定生产和边底水均匀推进。对常用排水采气工艺适应性进行了对比，指出克拉2气田目前最合适的排水采气工艺为井口增压和优选管柱,并对其开展了应用效果评价。结果表明:优选管柱和井口增压两种工艺可作为克拉2气田的排水采气工艺；对于出水气井而言，下入油管最优尺寸为62 mm，可有效携液生产并延长自喷生产时间；井口增压工艺可有效降低井口压力，释放地层能量，在井口压力降低6 MPa的情况下，自喷结束对应地层压力降低幅度可达10 MPa左右，大幅度延长了气井自喷周期。研究结果表明，井口增压可作为克拉2气田首选排水采气工艺，优选管柱可作为备选工艺。

Optimization and effect analysis of drainage gas recovery technology in Kela 2 gas field

The Kela 2 gas field is the main gas field for the West-East natural gas transmission project. Due to geological reasons, some gas wells in Kela 2 gas field have already produced water, which seriously affects the productivity and ultimate recovery of the gas wells. It is urgent to take drainage gas recovery measures to maintain the stable production of gas wells and the uniform advancement of edge and bottom water. The adaptability of the commonly used drainage gas recovery technologies was analyzed, and found that the most suitable drainage gas recovery technology in the Kela 2 gas field was wellhead pressurization and pipe string optimization, then the application effect of which was evaluated. The results show that: the pipe string optimization and wellhead pressurization can be used as the drainage gas recovery process in Kela 2 gas field; for water-producing gas wells, the optimal size of the running tubing is 62 mm, which can effectively carry liquid and prolong natural flow production. The wellhead pressurization process can effectively reduce the wellhead pressure and release the formation energy. When the wellhead pressure was reduced by 6 MPa, the corresponding formation pressure can be reduced by about 10 MPa after natural flow production, which greatly prolongs the gas well flowing production period. The research results show that wellhead pressurization can be used as the preferred drainage gas recovery process in the Kela 2 gas field, and the pipe string optimization process can be used as an alternative one.