摘要
为了明确温度对煤体吸附瓦斯性能的影响程度,根据Lang-muir等温吸附方程及单分子层定位吸附模型等相关理论,推导并分析了瓦斯吸附量、吸附常数与温度的关系,得出瓦斯吸附量随温度的升高而降低,吸附常数a与温度没有直接关系,而吸附常数b与温度存在直接联系。利用WY-98B型瓦斯吸附常数测定仪对赵楼3上煤层煤样进行了不同温度下的瓦斯吸附常数测定试验,试验温度分别选取293 K、298K、303K、308K、313K、318K、323 K,得到不同温度下煤样的吸附等温线,进而得到不同温度下的吸附常数值。对结果进行对比和验证,得到温度对煤体吸附常数的影响规律。结果表明:在压力条件一定时,煤对瓦斯吸附几率及吸附时间等影响瓦斯吸附量的主要因素均随温度的升高而减小,导致瓦斯吸附量随着温度升高而下降;吸附常数a只与煤体表面性质有关,但温度引起的比表面积变化对吸附常数a影响显著;吸附常数b取决于吸附温度T、吸附压力p以及煤体自身物理性能所决定的振动时间τ0。
The present article is to share our study results on the influence of temperature on coal adsorbing capability. For this purpose, we have analyzed and deduced the relation among the gas adsorption, the adsorption constant and the temperature involved. Furthermore, we have also worked out the effect of temperature on the adsorbing capability of coal in accordance with the theory of Langmuir isothermal adsorption equation, the adsorption constant and the corresponding temperature. Our analysis shows that the gas adsorption decreases with the increase of temperature. As to the adsorption constant a, it has no direct relation with temperature, whereas adsorption constant b is directly related with the temperature. In order to determine the adsorption constant of the coal sample from coal seam 3, which we take from Zhaolou mine at different temperatures by means of WY-98B adsorption constant determinator. We have also divided our test temperature range into seven grades, that is, 293 K, 298 K, 303 K, 308 K, 313 K, 318 K and 323 K, and obtained adsorption isotherms at different temperatures through experiments. And, next, careful observation and experiments enable us to find the regularities of the effects on the coal adsorption constant and the adsorption temperature through comparison and verification of the experimental results, which indicate that the key factors affecting the gas adsorption are the adsorption probability and the adsorption time. At a certain gas pressure, both the adsorption probability and the adsorption time tend to decrease with the increase of temperature. As a result, the gas adsorption tends to decrease with the increase of the temperature, too. Moreover, Langmuir constant a can only be related to the surface properties of the coal and changes in a specific surface area due to the temperature variation. In addition, the changes of temperature has also a direct effect on the relation of Langmuir constant a and adsorption temperature, whereas Langmuir constant b is dependent on the adsorption temperature T, the adsorption gas partial pressure p and the molecule vibration time ＆tau;0, which can be determined by the physical properties of coal, for under the same condition of adsorption gas partial pressure, Langmuir constant b is in direct proportion with T-1/2.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2012年第5期231-234,共4页
Journal of Safety and Environment
基金
长江学者和创新团队发展计划项目(IRT0843)
山东省科技发展计划项目(2010GSF10808)
