煤层气井产能影响因素分析及对策

Influence Factors of Production Capacity and Strategy on Coalbed Gas Wells

司淑平;李文峰;马建民

Si Shuping, Li Wenfeng, Ma Jianmin

中原油田分公司煤层气事业部

Coalbed Gas Operating Division , Zhongyuan Oilfield Company , SINOPEC, Henan 457001 ,P. R. China

在煤层气勘探中,因某些因素制约其产能,影响了煤层气投入开发的进程。煤层气原始地层压力、压裂效果、气井后期维护过程中对煤层的污染等是导致煤层气井产能低的主要因素。针对这些影响因素,提出了解决的对策:依据煤层变质程度选择压裂方法;实行对煤层围岩压裂方法;在煤层气井后期维护中防止污染的方法,即:冲砂、洗井循环液中控制固相颗粒含量;施工作业中控制波动压力的产生;冲砂洗井作业要求循环液与地层流体相配伍,并加杀菌剂;选择合理的排采参数。采取上述办法解决影响煤层气产能问题,将会收到较好的效果。

As some factors restrict production capacity and influence the process of coalbed gas development during coalbed gas exploration , the problerns of influencing factors of coalbed gas production capacity need to be solved. This paper points out that the original formation pressure of coalbed gas , the effect of fracturing , the contamination to coalbed during the post maintenance of gas wells are the primare factors which lead to the decrease of production capacity of coalbed gas wells through serious analyses with combination of theory and practice. We put forward the methods to solve the influential factors : ① the choice of fracturing method based on the metamorphic grade of coalbed. ② the practice of fracturing method to coalbed wall rock. ③ the methods to prevent the contamination during the Post maintenance of coalbed gas wells , namely the controls on the solid grain content in the flushing and drilling circulation fluid; the control the generation of fluctuation of pressure during the production ; the flushing and washing task need the match of circulation fluid and formation fluid , plus germicide ; the choice of reasonable discharge and recovery paramters. Adopting the albove methods to solve the problems influencing the production capacity of coalbed gas , better effects will be received.