As an indispensable energy source, lignite is almost exclusively used in power generation m TurKey, To assess me quality level of Turkish lignite, a multivariate statistical analysis was conducted. The relationship am...As an indispensable energy source, lignite is almost exclusively used in power generation m TurKey, To assess me quality level of Turkish lignite, a multivariate statistical analysis was conducted. The relationship among the lignite quality parameters has been investigated using a response method that is the logistic regression method. The analysis determines the effect of multiple predictor variables such as moisture, ash and sulphur presented simultaneously to predict membership of the two calorific value categories. By this way, a reliable binary response regression structure was constructed considering all the lignite fields in Turkey. Both the experiments on identifying the influential measurements and the measure of goodness of fit indicated that the overall model has a big capability to exhibit the relationship among the parameters of the Turkish lignite.展开更多
In order to analyze the origin of carbon monoxide(CO) in coal seams, stress–strain experiments under temperature of 50, 150 and 250 °C were conducted using lignite from Kailuan mining area. Fourier transform inf...In order to analyze the origin of carbon monoxide(CO) in coal seams, stress–strain experiments under temperature of 50, 150 and 250 °C were conducted using lignite from Kailuan mining area. Fourier transform infrared spectroscopy and elemental analysis were carried out before and after deformation of the samples. The results indicated that CO generated at 150 and 250 °C; the gas component was mostly oxygen(O_2), with small amount of carbon dioxide(CO_2), methane(CH_4) and hydrogen(H_2). At 50 °C, O_2 and a little CO_2 were observed and no CO was found. The carbon content of the coal samples increased slightly after deformation, and the oxygen content, H/C ratio, and O/C ratio decreased. The molecular structure of coal displayed different evolution characteristics at various temperatures. At 50 and 150 °C, the falling off of side chains, broken of ether bond and directional realignment of the aliphatic chains resulting in the formation of long chains were the main performance of coal molecular structure evolution. While at 250 °C, the side chains fell off and short chains formed. Furthermore, at both 150 and 250 °C, condensed degree of aromatic ring increased. Under the action of temperature and pressure, CO forms in two ways.The first is that ether bond breaks, oxygen and carbon atoms combine together and forms CO, or O_2 forming in the broken of ether–oxygen bond leads to the oxidation of free radicals and resulting in the formation of CO. And the second is that CO derives from falling off of C=O group.展开更多
Preliminary sink-float experiments on high-sulfur coal was done in some mining areas and carried on elementary analysis, industrial analysis, and ashcontent analysis. Through the experiments, definite middlings, and g...Preliminary sink-float experiments on high-sulfur coal was done in some mining areas and carried on elementary analysis, industrial analysis, and ashcontent analysis. Through the experiments, definite middlings, and gangue, the phase analysis of sulfur was carried on, by which a good understanding of sulfur characters in raw coal was achieved.展开更多
文摘As an indispensable energy source, lignite is almost exclusively used in power generation m TurKey, To assess me quality level of Turkish lignite, a multivariate statistical analysis was conducted. The relationship among the lignite quality parameters has been investigated using a response method that is the logistic regression method. The analysis determines the effect of multiple predictor variables such as moisture, ash and sulphur presented simultaneously to predict membership of the two calorific value categories. By this way, a reliable binary response regression structure was constructed considering all the lignite fields in Turkey. Both the experiments on identifying the influential measurements and the measure of goodness of fit indicated that the overall model has a big capability to exhibit the relationship among the parameters of the Turkish lignite.
基金financial support from the National Science foundation of China(No.41430317)the Discipline Innovative Engineering Plan sponsored by the Ministry of Education of China+1 种基金the State Administration of Foreign Experts Affairs of China(No.13023)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘In order to analyze the origin of carbon monoxide(CO) in coal seams, stress–strain experiments under temperature of 50, 150 and 250 °C were conducted using lignite from Kailuan mining area. Fourier transform infrared spectroscopy and elemental analysis were carried out before and after deformation of the samples. The results indicated that CO generated at 150 and 250 °C; the gas component was mostly oxygen(O_2), with small amount of carbon dioxide(CO_2), methane(CH_4) and hydrogen(H_2). At 50 °C, O_2 and a little CO_2 were observed and no CO was found. The carbon content of the coal samples increased slightly after deformation, and the oxygen content, H/C ratio, and O/C ratio decreased. The molecular structure of coal displayed different evolution characteristics at various temperatures. At 50 and 150 °C, the falling off of side chains, broken of ether bond and directional realignment of the aliphatic chains resulting in the formation of long chains were the main performance of coal molecular structure evolution. While at 250 °C, the side chains fell off and short chains formed. Furthermore, at both 150 and 250 °C, condensed degree of aromatic ring increased. Under the action of temperature and pressure, CO forms in two ways.The first is that ether bond breaks, oxygen and carbon atoms combine together and forms CO, or O_2 forming in the broken of ether–oxygen bond leads to the oxidation of free radicals and resulting in the formation of CO. And the second is that CO derives from falling off of C=O group.
文摘Preliminary sink-float experiments on high-sulfur coal was done in some mining areas and carried on elementary analysis, industrial analysis, and ashcontent analysis. Through the experiments, definite middlings, and gangue, the phase analysis of sulfur was carried on, by which a good understanding of sulfur characters in raw coal was achieved.
