| China’s coal is rich in resources and is the main energy pillar.However,the burning of high-sulfur coal is one of the important factors causing environmental pollution,among which acid rain pollution is the most serious.Southwest in China is given priority to with high sulfur coal,whose combustion seriously hindered the clean utilization of coal resources and caused some security problems.In order to reduce the sulfur pollution of coal burning process,improve regional environmental safety and so on,in combination with the practical situation of codium mining area coal desulfurization,proposed "the high calorific value,low emission" desulfurization research ideas,and studied the desulphurization of high sulfur coal in songalga mining area.By means of experiment and theoretical analysis,desulfurizing agent was used to screen the microwave enhanced desulfurization experiment,and the removal mechanism of sulfur in coal was explored,and the main results were obtained:(1)On the basis of summarizing the methods of coal burning and desulphurization at home and abroad,the present situation of desulfurization before coal burning in songzao mining area is investigated and analyzed.The coal samples were measured by morphological sulfur,coal quality analysis,industrial analysis and characterization,and the coal with high organic sulfur content was selected as the experimental object.(2)Through a single chemical desulfurization method for desulfurization agent preliminary screening sequence,loss of calorific value concept is put forward,and the comprehensive evaluation of desulfurization effect of different desulfurization auxiliaries was carried out by means of variation coefficient method,then citric acid was determined as a desulfurizing agent.Microwave-assisted citric acid improved desulfurization experiment was carried out,and the effect of five factors(Particle size,reaction temperature,irradiation time,microwave power,citric acid concentration)on the sulfur removal rate of organic sulfur was investigated by single factor experiment.The orthogonal experiment was carried out with three factors(Reaction temperature,irradiation time and citric acid concentration)of the concentration of citric acid.Finally,the optimum desulfurization experiment parameters were given,and the sulfur removal rate of organic sulfur was 74.13%.(3)The desulfurization effect of 5 kinds of coal samples was verified by the optimal desulphurization parameter,and it was found that the microwave assisted citric acid enhanced desulfurization method was suitable for the coal with high organic sulfur content.The FT-IR and XRD response analysis was carried out,and the results showed that the citric acid had a directional removal effect on the organic sulfur of FeS and sulfonate organic sulfur in coal,and there was no direct response relationship between sulfone and organic sulfur.In the process of desulfurization,the complex reaction between citric acid and Fe3+ in coal can prevent the removal of sulfur,and the low concentration of citric acid can be selected for desulphurization.Through this study,the theoretical foundation is established for the research of the microwave assisted citric acid desulfurization method.This method can effectively remove most of the organic sulfur in coal,and can provide engineering reference for the development of coal pre-combustion desulfurization technology in Songzao mining area. |
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