Experimental Study On Evolution Law Of Pores-Fissures In Oil Shale By Microwave Pyrolysis

My country’s oil shale is rich in reserves,widely distributed,and has great potential for resource development.However,there are certain technical difficulties in development and utilization.Therefore,researching oil shale retorting process is the key to whether it can become an alternative energy source for oil.Taking the oil shale of the East Fushun open-pit mine as the specific research object,under the condition of microwave pyrolysis of oil shale,the pores and fractures of oil shale after pyrolysis under the action of different microwave powers were explored through scanning electron microscopy and micro-CT observation methods.The structural evolution characteristics and the permeability change law,the analysis results are as follows:First,the changes in the structure of oil shale before and after microwave exposure were studied by means of scanning electron microscopy,and the BSE images were processed by Matlab software to obtain the change of organic matter in oil shale under different powers.The change of pore size and porosity of oil shale before and after pyrolysis.It is found that after microwave pyrolysis,with the increase of power and temperature,the organic matter inside the oil shale specimen is more easily decomposed into gaseous or liquid substances,which increases its own The porosity and microwave absorption area of the oil shale are high,and new pores and cracks are formed in the process of pyrolysis and fracturing of oil shale.Secondly,the micro-CT experiment was used to study the internal pore structure of the oil shale specimen under the action of different microwave powers,and the digital core was reconstructed by combining with Avizo software,and the pores in the whole space of the oil shale specimen were extracted.By analyzing the pore mesostructure characteristics such as surface area,pore size distribution and permeability,by comparing the pore structure of oil shale with different powers,it is found that under the action of 600 W power,the maximum porosity of oil shale at600℃ is 29.01%,and the pores are extremely developed.The oil shale pyrolysis reaction is complete;the oil shale pyrolysis reaction is the fastest under the action of800 W power,but due to the intense reaction,the shale oil and gas cannot be discharged in time in the later stage,and the residual oil and gas traces are obvious.Finally,combined with the changes in the apparent structure and internal structure of oil shale before and after microwave pyrolysis,it is found that microwave pyrolysis of oil shale can increase the porosity and permeability of oil shale.The time for shale to reach the target temperature is shortened,which increases the possibility of secondary reaction of oil shale,and also leads to a decrease in the yield of oil shale.Microwave pyrolysis of oil shale is not as high as possible.out to maximize.The research results will help to provide a theoretical reference for the application of microwave radiation technology in the field of oil shale mining,and then provide a theoretical basis for the application of microwave technology to realize the industrialized mining of oil shale.The paper has 75 figures,4 tables,and 78 references...