Studies on Gasification of Coal under Pressure Hydrogasification of Taiheiyo Coal under Non-isothermal Conditions

In order to clarify the hydrogasification reaction of coal, the change in weight loss and the corresponding gaseous products were measured at various hydrogen pres-sures under non-isothermal conditions.The evolutions of gaseous hydrocarbons by hydrogasification began from about 420°C, reached their respective maximam rate at the same temperature of about 550°C and then decreased irrespective of the hydrogen pressure. After showing the minima at about 600°C, the formations of methane and ethane again increased to the clear second maxima. It was found that below 600°C the ratio of the formation rate of ethane to that of methane remained constant regardless of the reaction temperature, but increased with increase in hydrogen pres-sure. This suggests that some active portion of carbon in coal structure will simultaneously produce gaseous hydrocarbons including ethylene and propane.Above 600°C, methane was predominatingly produced from fixed carbons at a rate proportional both to the hydrogen pressure and to the weight of residual coal.