中国安全科学学报 ›› 2023, Vol. 33 ›› Issue (7): 58-67.doi: 10.16265/j.cnki.issn1003-3033.2023.07.0116

• 安全工程技术 • 上一篇    下一篇

多因素对液态CO2冻融致裂煤体的影响试验研究

周西华1,2(), 周露函1,3,**(), 姜延航1, 白刚1, 刘天祥1, 王学鹏1   

  1. 1 辽宁工程技术大学 安全科学与工程学院,辽宁 葫芦岛 125105
    2 矿山热动力灾害与防治教育部重点实验室,辽宁 葫芦岛 125105
    3 铜仁职业技术学院 工学院,贵州 铜仁 554300);
  • 收稿日期:2023-02-20 修回日期:2023-05-10 出版日期:2023-07-28
  • 通讯作者:
    ** 周露函(1995—)女,贵州毕节人,硕士,讲师,主要从事安全工程方面的工作。E-mail:
  • 作者简介:

    周西华 (1968—),男,安徽濉溪人,博士,教授,博士生导师,主要从事煤矿火灾防治、瓦斯防治、高温热害防治专业的教学与科研工作。E-mail:

    白刚,副教授

  • 基金资助:
    辽宁省教育厅青年项目(LJ2019QL002); 大学生创新创业训练计划项目(X202010147099); 辽宁工程技术大学学科创新团队资助项目(LNTU20TD-29)

Experimental study on influence of multiple factors on liquid CO2 freeze-thaw cracking coal

ZHOU Xihua1,2(), ZHOU Luhan1,3,**(), JIANG Yanhang1, BAI Gang1, LIU Tianxiang1, WANG Xuepeng1   

  1. 1 College of Safety Science and Engineering, Liaoning Technical University, Huludao Liaoning 125105, China
    2 Key Laboratory of Mine Thermodynamic Disasters and Control of Ministry of Education (Liaoning Technical University), Huludao Liaoning 125105, China
    3 Engineering College, Tongren Polytechnic College, Tongren Guizhou 554300, China
  • Received:2023-02-20 Revised:2023-05-10 Published:2023-07-28

摘要:

为研究多因素耦合对液态CO2冻融致裂煤体的影响,采用自主研发的液态CO2冻融致裂试验装置,利用核磁共振测试技术,测定不同影响因素下液态CO2冻融致裂后煤体的孔隙度,分别研究液态CO2冻结时间(t)、冻融循环次数(n)和煤体含水饱和度(W)对煤体孔隙度(φ)的影响;采用响应曲面法设计试验,构建φtnW的二次回归响应曲面模型,分析tnW单独及耦合作用时对φ的敏感程度及影响特征,并预测优化与验证不同影响因素下的φ。结果表明:随着t的延长和n的增多,φ呈指数函数关系变化,随W的增大,φ呈线性关系增加;影响因素tnW均为φ的极显著项(显著性判别值P<0.01),对φ影响的主次关系为:n>W>t。交互项nt交互作用极显著,nW交互作用次之,Wt交互作用不显著,对φ影响的主次关系为:nt>nW>Wt。模型预测当tnW分别为57 min、19次、96%时,φ达到最大值(9.47%),4组试验值与模型预测值平均误差为2.98%,所测φ平均值为9.58%,φ较优化之前(8.94%)提高了7.16%。

关键词: 冻融致裂, 液态CO2, 孔隙度, 冻结时间, 冻融循环次数, 含水饱和度

Abstract:

In order to study the coupling influence of multi-factor on liquid CO2 freeze-thaw cracking coal, a liquid CO2 freeze-thaw cracking test device was designed. The nuclear magnetic resonance testing technology was used to measure the porosity of coal after liquid CO2 freeze-thaw cracking under different influencing factors. The effects of liquid CO2 freezing time (t), number of freeze-thaw cycles (n) and water saturation (W) on coal porosity (φ) were studied. The quadratic regression response surface model of φ with t, n and W was constructed by response surface method. The sensitivity of t, n and W to φ single and coupled was analyzed, and the influence characteristics were predicted, optimized and verified under different influencing factors. The results show that the φ changes exponentially with the increase of t and n, and linearly with the increase of W. The influencing factors t, n and W are all extremely significant terms of φ (significant discriminant value P<0.01), and the influence relationship of to φ is as follows: n>W>t. The interaction between nt and Wt is very significant, followed by nW and Wt. The primary and secondary effects on φ are nt>nW>Wt. When t, n and W are 57 min, 19 times and 96%, respectively, the maximum value of φ is 9.47%. The average error between the four test values and the predicted value of the model is 2.98%, and the measured average value of φ is 9.58%, which is 7.16% higher than that before optimization (8.94%).

Key words: freeze-thaw cracking, liquid CO2, porosity, freeze time, number of freeze-thaw cycles, water saturation