自燃煤矸石山覆盖层空气阻隔性的测试装置及其可靠性  

Research on the equipment and its reliability to test air barrier property of covering layer of coal gangue piles

作　　者：陈胜华[1] 郭陶明[1] 胡振琪[2] 

机构地区：[1]太原理工大学阳泉学院,山西阳泉045000 [2]中国矿业大学(北京)土地复垦与生态重建研究所,北京100083

出　　处：《煤炭学报》2013年第11期2054-2060,共7页Journal of China Coal Society

基　　金：国家高技术研究发展计划(863)资助项目(2009AA06Z320);山西省自然科学基金资助项目(2011011030-3)

摘　　要：检测覆盖层的空气阻隔性，是自燃煤矸石山治理实践亟待研究和解决的问题，也是自燃煤矸石山覆压效果监测的迫切要求。研究了一种大尺寸土质试样透气性的测试设备，利用正压差法直接测定自燃煤矸石山覆盖层试样的空气阻隔性，并对覆盖层阻燃效果进行有效性评价。设备由密闭气腔、压力源、计量元件三大部分组成。密闭气腔直径为120—240mm，由3段腔体依次密封连接而成，上游段为注气腔，下游段为排气腔，中间段为放置有待测土质试样的测试腔；压力源为空气压缩机并串联空气减压阀；计量元件为气压表、流量计或可读气体流量的仪表。对设备性能进行检测，气密性检测表明该设备在压差0．2MPa时，10h之内可以保证密闭，能满足本试验中土质材料覆压阻燃效果的测试要求；对设备进行数据重现性及重复性检测，结果显示偏差系数均小于10％。对一组不同密实度粉煤灰试样的空气渗透性进行了测试，试验结果表明，不同试样的空气渗透速度与试验压差均呈线性比例递增，且线性模型的斜率随试样密实度增加而减小；在压差小于0．05MPa的范围内，根据透过阻隔性较差的粉煤灰的空气渗流速度计算雷诺数，结果均小于1；不同的压实功能作用下，密实度大的试样渗透率较小，空气阻隔性能好，设备检测结果符合客观实际。Detecting the air barrier property of covering layer of coal gangue is the major problem, which needs to be studied and solved in the treatment practice of coal gangue piles with spontaneous combustion. It is also the urgent re- quirement for monitoring compaction effect of covering layers of coal gangue piles with spontaneous combustion. Au- thors developed a testing equipment of air permeability under the conditions of large-size soil samples, which can di- rectly test the air barrier property of soil samples by simulating or in-situ sampling the covering layer of coal gangue piles with spontaneous combustion according to the positive pressure difference method, and also can evaluate the ef- fectiveness of stopping combustion by the covering layer. The equipment includes three parts ： airtight chamber, pres- sure source and measuring elements. Airtight chamber： Diameter is 120 -240 mm, which includes three sealed and connected chambers, the top one is for air injection, bottom one is for exhaust air, the middle one is the place for soil samples. The pressure source ： includes the air compressor and air reducing valve. Measuring element includes a barom- eter, and flow meter or readable air flow meter. To detect the equipment performance, air tightness testing indicate thatthe equipment in the pressure of 0.2 MPa, can guarantee the closed within 10 hours, can satisfy the overlying soil ma- terials in this test pressure test requirements of effectiveness of stopping combustion. Testing repeatability and data re- production of the equipment, results show that the deviation coefficient is less than 10%. The air permeability test of a group of fly ash with different compactness was took, it show that the air permeability speed of different samples is in- creased with experimental pressure differences linearly, and the slope of the linearly model decreases with the increase of the sample compactness. In the range of pressure is less than 0.05 MPa, according to the poor air flow rate through the barrier of Infer

关 键 词：自燃煤矸石山 覆盖层 空气阻隔性 测试装置 渗透率 阻燃效果 

分 类 号：X859[环境科学与工程—环境工程]