煤层气井排采制度及配套工艺技术

Drainage-production system and matching engineering technology for coalbed methane wells

根据延川南煤层气试验区煤层气井排采过程中,因排液速度不合理和排采工艺不完善,造成煤层气排采井生产周期短、产气量低、资料录取不准确的现状,通过试验区45口井排采工作的摸索和试验,探索了"五段制"的工作制度和合理的套压范围,形成了防砂防气锁的斜井泵排采技术、电子压力计地面直读监测技术、捞砂泵捞砂技术,结果表明"五段制"的排采制度保证了延川南试验区煤层气排采井产气量稳步上升,日产气量超过16 000 m3,生产周期由224 d延长至353 d。

During the drainage-production of coalbed methane （ CBM） in southern of Yanchuan ,because of the un-reasonable drainage speed and imperfect techniques for the drainage -production,the drainage wells have many problems such as short production cycle ,low gas production ,and inaccurate information acquisition .Based on the experiences from 45 wells in the test area ,it was carried out studies on the “five sections”work system and a reasonable range of casing pressure .As a result ,the matching technologies were formed ,which include the drainage -production technology by devia-ted well pump with anti -sand and anti -airlock,the ground direct -reading monitoring technology by electronic -ma-nometer ,and the bailing technology by bailing sand pump .The results showed that the “five sections”work system can en-sure the gas production rate of CBM wells rising steadily ,with a daily gas production rate of over 16 000 m3/d.The matc-hing technology can prolong the production cycle from 224 days to 353 days .