College of Safety Engineering,North China Institute of Science and Technology College of Geosciences & Surveying
Engineering,China University of Mining & Technology(Bejingy)

为研究煤层气排采过程中煤岩组分对煤粉产出的影响,开展了单相流驱替煤粉产出的流态物理模拟试验,通过改变单相流驱替流速及围压的大小,分析了型煤样品中不同煤岩组分条件下煤粉的动态产出规律。结果表明:随流速及围压的增加,煤粉产出均有增大的趋势;黏土含量越高,煤粉产出量越大,且产出煤粉受驱替流速变化的影响越大;镜质组含量越高,围压的增大会使煤粉的产出速率减小,且产出煤粉受围压变化的影响越大;围压不变,随驱替流速增大,煤岩渗透率有增大的趋势,且流速越大,不同煤样渗透率变化趋势越接近。煤中黏土矿物可显著影响渗透率,黏土矿物含量越高,渗透率提升速率越快;流速保持不变,随着围压的增大,煤岩渗透率有降低趋势;同时,较低的黏土矿物含量无法有效地聚合分散的煤粉颗粒,表现为渗透率持续降低。

In order to study the impact of maceral component on pulverized coal output during the coalbed methane producing process,the physical simulation experim ents of the pulverized coal output with the single-phase flow displacement were conducted.The dynamic output rules of pulverized coal under the different maceral compon ents conditions in coal samples were analyzed by changing displacing flow velocity and the size of confining pressure of the single-phase flow. The experimental results sh owed that pulverized coal output had an increasing tendency with the increasing of flow velocity and confining pressure. The higher was clay content,the larger was pulveri zed coal output,and the pulverized coal output was more affected by the changes of displacing flow velocity.The higher was vitrinite content,the less was pulverized coal ou tput with the increasing of the confining pressure, and the greater impact it had with the changes of confining pressure on pulverized coal output.Moreover,in the stable conf ining pressure condition,coal permeability had an increasing tendency with the increasing of displacement flow velocity. The permeability of different coal samples became close with the increasing of the flow velocity. Furthermore,it was found in this study that the clay minerals in coal coud affect the changes of permeability significantly. The h igher was the clay minerals content,the faster was the upgrading rate of the penetration. In the stable flow velocity condition,the permeability of the maceral had a decreasi ng tendency with the confining pressure increases. Meanwhile,low clay mineral content coud not aggregate dispersed coal particles effectively.t showed that permeability C ontinued to decrease.

国家科技重大专项资助项目(2011ZX05038-001)；国家自然科学基金资助项目(41272179,41272181)；