相变蓄热作用下煤体增透影响因素研究

Study on influencing factors of coal permeability enhancement under effect of phase change thermal storage

为了研究相变蓄热作用下煤体增透的影响因素,开展了相变蓄热煤体增透试验和煤体瓦斯渗流试验,分别分析了相变蓄热作用下相变初始温度、相变次数、煤体含液率、煤体破碎程度等因素对煤体渗透率变化的影响。研究结果表明:煤体渗透率增幅随相变初始温度的增加呈线性增长;煤体含液率和相变次数是相变蓄热作用下影响煤体增透效果的重要因素,随着煤体含液率或相变蓄热次数的增加,煤体渗透率增幅整体上呈指数型增长,分别最大可增至556.04%和406.92%,但是当相变蓄热次数增高到一定程度时,煤体渗透率增加的幅度快速减小;且煤体增透效果和煤体破碎程度关系密切,当煤体碎程度较高时,煤体渗透率增幅也较明显。

In order to study the influencing factors of coal permeability enhancement under the effect of phase change thermal storage,coal permeability enhancement experiment and coal gas seepage experiment were conducted,and the effects of thermal storage transition temperature,phase change times,liquid content and crushing degree on the permeability change of coal were analyzed respectively.The results showed that the coal permeability increased linearly with the increase of phase transition temperature;the liquid content and phase change times were main important factors of the coal permeability enhancement under the effect of phase change thermal storage.With the increase of the liquid content of coal or the phase change times of phase change thermal storage,the coal permeability increased exponentially as a whole,and the maximum increased to 556.04%and 406.92%respectively.However,when the number of phase change times reached to a certain value,the increase of coal permeability slowed down gradually.And the permeability enhancement effect of coal was closely related to the degree of coal crushing,when the degree of coal crushing was high,the increase degree of the coal permeability was also more obvious.