CAJ | 학술논문

90%以上的煤层气以吸附状态附着在煤的内表面上,煤层气的产出是一个区别于常规天然气的 "排水—降压—解吸—扩散—渗流" 的复杂过程.我国煤层气储层条件较差,具有低孔、低渗、非均质性强的特点,普遍存在常规开采方式开发效果差的问题.为提高煤层气单井产量,实现商业化开采,必须对储层进行增产改造,促进排水降压,提高煤层气单井产量,水力压裂改造技术是当前煤层气增产的首选方法,也是已被证明的煤层气开采的一种有效的增产方法.论述了水力压裂增产渗流机理及其效果评价方法,并进行了实例分析.表明通过对煤层进行水力压裂,能够改善井底渗流条件,提高储层的渗透能力; 煤层渗透率、表皮系数及裂缝导流能力和裂缝半长是评价煤层气水力压裂增产效果的主要参数.
90%이상적매층기이흡부상태부착재매적내표면상,매층기적산출시일개구별우상규천연기적 "배수—강압—해흡—확산—삼류" 적복잡과정.아국매층기저층조건교차,구유저공、저삼、비균질성강적특점,보편존재상규개채방식개발효과차적문제.위제고매층기단정산량,실현상업화개채,필수대저층진행증산개조,촉진배수강압,제고매층기단정산량,수력압렬개조기술시당전매층기증산적수선방법,야시이피증명적매층기개채적일충유효적증산방법.논술료수력압렬증산삼류궤리급기효과평개방법,병진행료실례분석.표명통과대매층진행수력압렬,능구개선정저삼류조건,제고저층적삼투능력; 매층삼투솔、표피계수급렬봉도류능력화렬봉반장시평개매층기수력압렬증산효과적주요삼수.
More than 90% coalbed methane ( CBM) is absorbed at the interior surface of coal. CBM production is a com-plex process, different from conventional natural gas characteristic of "drainage-decompression-desorption-seepage" . CBM reservoir in China is characterized by low porosity, low permeability and strong heterogeneity. Normally, it is very difficult to exploit CBM with traditional methods. To increase single-well CBM output and promote commercial production, reservoir stimulation has to be carried out, to drain water away and drop pressure. So hydraulic fracturing is currently the first method to be selected for CBM stimulation, and it is also proved to be effective for CBM exploitation. We discussed the principles of seepage and the methods for effect evaluation, and made a case study. It was shown that hydraulic fracturing could improve bottom-hole seepage conditions and enhance seepage capacity. Coalbed permeability, skin coefficient, frac-ture conductivity and fracture half-length were found important for evaluating CBM stimulation effect with hydraulic fractu-ring.