Study On Temperature Variation Characteristics In Adsorption And Desorption At Different Points On Coal Sample Surface

With the rapid development of the economy,the demand for energy is increasing.On the one hand,traditional resources such as oil and coal are increasingly depleting.On the other hand,solar energy,wind energy and other emerging energy supply shortage,and the development is restricted by many constraints.As an environmentally friendly energy,more and more attention has been paid to coalbed methane.The development of coalbed methane resources has many benefits.coalbed methane,also called gas,is a kind of mineral property which accompanies coal.The main component of the coalbed methane is methane,which is inflammable when it comes in contact with an open flame.The methane is a major cause of frequent accidents in coal mining.Methane has a great influence on the greenhouse effect,20 times greater than carbon dioxide.If discharged at will,it will do a further harm on the environment.If extracting coalbed methane in advance,the probability of occurrence of coal and gas outburst,gas explosion and other accidents can be reduced.Meanwhile,as a kind of clean energy,coal bed gas has the characteristics of high calorific value and no pollution after combustion.Our country is rich in coalbed methane.With Reasonable extraction and use of coal seam gas,we can effectively solve the problem of lack,uneven distribution of resources.The occurrence of coalbed methane is influenced by many factors,such as coal macerals,coal rank,reservoir pressure and water,unevenly distributed in geographical distribution.The Gas Content in the Coal B is associated with the ability of coal to adsorb gas.The adsorption heat will be produced in the adsorption process.Using the principle of infrared imaging,this paper will study the characteristics of coal adsorption gas from the viewpoint of temperature.The main research contents are as follows:(1)At the beginning of adsorption,the temperature of anthracite and lean coal rose rapidly in a short time and then remained stable around a certain value.At the beginning of desorption,the temperature dropped sharply,and then the rate of decline slowed down,and finally remained stable around a certain value.The greater the temperature rose in adsorption,the more evident temperature decreased in desorption.In the process of adsorption and desorption,the temperature changed to accord with the exponential function and logarithmic function respectively.The degree of metamorphism of coal also influenced the characteristics of temperature change during adsorption and desorption.(2)The temperature rise of coal sample of different coal regions was various,and their gas adsorption capacity was various,too.There was a positive correlation between the magnitude of coal temperature rise and the capacity of gas absorption.The coal sample,which had greater temperature rise,had more gas adsorbed.(3)The Interpolated image showed that,in adsorption,the temperature rise of coal plane varied with inhomogeneity.That is,the temperature rise in each coal sample area is different.During adsorption,the temperature rise in some areas was obviously greater than that in the adjacent area;and there was also a larger temperature drop in those areas when desorbed.(4)The distribution of temperature in the sampling region could be quantitatively analyzed by plotting the isotherms on the interpolated image.The difference coefficient was proposed.It can relate the temperature to the adsorption capacity and can characterize the difference of gas adsorption capacity in different regions of coal.So,hopefully,it can be used to evaluate the feasibility of coalbed methane industrial mining in this area.