多裂缝压裂改造技术在煤层气井压裂中的应用

Application of Multiple cracks Fracturing Technique to Coalbed Gas Wells

由于煤层没有空化作用 ,而且大部分煤储集层的渗透性很差 ,所以需要采用压裂措施从煤层中经济地开采天然气产品 .然而有效的煤层水力压裂增产措施由于下述诸多原因而面临严峻的挑战 :煤力学性质的复杂性 ,普遍存在的天然裂缝 ,煤层对压裂液伤害的高度敏感性 ,对压力敏感的煤层渗透性等 .采取新的压裂改造措施 ,在煤层中造多条裂缝 ,以更好地沟通天然裂缝 。

In order to produce more coalbed gas, it is necessary to treat coalbeds by fracturing because of no cavitation and low permeability of coalbeds. However, hydraulic fracturing is faced with some difficulties: complexity of the mechanic property of coal, natural cracks in coalbeds, high sensitivity of coalbeds to fracturing liquid damage, and sensitivity of coalbed permeability to pressure. For this reason, the author puts forward that multiple cracks are produced in coalbed by high energy gas fracturing (HEGF) or HEGF combination techniques, they can link up the natural cracks for the purpose of increasing the yield of coalbed gas.