含瓦斯煤相似材料研制及其突出试验应用

采用相似物理模拟试验研究煤与瓦斯突出机制和规律是目前有效的方法,含瓦斯煤体相似材料是突出定量模拟的关键因素。研制出一种新型的含瓦斯煤体相似材料,该相似材料以一定粒径分布的煤粉为骨料,以腐植酸钠水溶液为胶结剂,混合压制成型后干燥。大量正交配比试验表明:在成型压力15 MPa下,相似材料的重度、孔隙率趋于稳定并与原煤十分接近;相似材料抗压强度高,可调范围达0.5~2.8 MPa,与胶结剂浓度近似呈线性正比关系;吸附解吸试验表明,相似材料的吸附性良好,其与原煤的吸附等温线一致;并且具有材料价格低廉、无毒副作用、配比简单、性能稳定和各物理力学参数调节方便等特点,可用来模拟不同强度原煤。采用相似材料制作的型煤开展了煤与瓦斯突出试验,成功模拟了煤与瓦斯突出现象和过程,证明该相似材料能很好地模拟具有吸附解吸特性的含瓦斯煤体。

Development of a similar material for methane-bearing coal and its application to outburst experiment

An effective approach to studying the mechanism and development of coal outburst is to conduct the outburst model tests using similar materials. A new similar material for the methane-bearing coal is developed. After mixing a pulverized with a specified particle size distribution as aggregate and a humid acid sodium aqueous solution as a cementing agent, the similar materials is made by sequentially shaping and drying the mixture. A number of orthogonal-ratio tests show that the similar material is quite similar to the raw coal with regard to bulk density and porosity under a 15 MPa forming pressure; and the material has a high compressive strength ranging from 0.5-2.8 MPa, which varies almost linearly with cementing agent concentration. Adsorption and desorption tests show that the similar material perform very well in regard to adsorption, and its adsorption isotherm agrees with that of the raw coal. The developed similar material possesses such advantages as cost-effectiveness, non-toxicity, easy manufacture, stable performance and flexible functions, and can be used to simulate the behaviors of the raw coal with different strengths, Model tests of methane outburst are carried out using the made similar material, and the phenomenon and processes of methane outburst are successfully revealed; it is shown that the similar material can simulate adsorptive and desorptive behaviors of methane-bearing coals.