Researched On The Behavior Of Coal Catalytic Gasification By TGA

The technology of coal gasification, as one of the high efficient and clean utilization of coal, has been highly favored among many people, because it has several advantages such as wide range of utilization, gained the products of different component according to the need and the reactor of many types can be used. Lots of laboratory studies have reached the level of industrial application, and for the sake of improved the gas efficiency and lowered the temperature of gasification ulteriorly, many laboratory studies about the catalytic gasification of coal were appeared before 70 years. However, to the present, the catalytic gasification of coal has not been applied for any process of industrial production. The research of this paper was also based on the level of laboratory studies, analyzed the catalytic gasification behavior of four different coals elementarily by TGA.Tongchuan coal, Hancheng coal, Xinjiang coal and Yunnan coal were used in this paper, and K₂CO₃, Na₂CO₃, KCl, CaO and compound catalysis (MgSO₄+KCl) as the catalysis used in coal gasification. Two loaded ways (Volumetric impregnation and Mechanical mixing) were applied in this research, Respectively loaded the five catalysis on the four different types of coals with different concentration . Firstly, the catalytic gasification behavior of Tongchuan coal were analyzed by TG, then the catalytic gasification behavior of other three different types of coals were analyzed synthetically, the results were carried out: K₂CO₃ and Na₂CO₃ as the best accepted catalysis of coal gasification showed the high catalytic activity for the four different types of coals, the gasification efficiency was improved and the gasification temperature was reduced mostly, and the efficiency of the catalytic gasification of these coals was improved with increasing of the catalysis concentration; the catalytic activity of KCl was better on these coals, and the efficiency of the catalytic gasification of these coals have no relation with the catalysis concentration; the catalytic activity of compound catalysis (MgSO₄+KCl) was not very good on these coals, the reasons may be the proportion is not fit these coals; CaO has no catalytic activity on these coals, the reasons is that the gasifying agent(CO₂) may not fit CaO catalysis, or the loaded ways made the Ca²⁺ can not dispersed in the coal equably. According to the dynamics analysis of the gasification reaction of Hancheng, Xinjiang and Yunnan raw coal and these coals which loaded catalysis, it was proved that the catalysis could really reduced the activation energy of coal, and proved the results of TG analysis in this paper.It was carried out that different types of coals have different selectivity for different catalysis, and the gap of catalytic activity of different catalysis on Hancheng coal were so large, and oppositely on Yunnan coal, and what's more, the four types of catalysis except CaO were truly affected the gasification process of these coals.