The Process Design And Experimental Study On Catalytic Gasification Of Fujian Anthracite In Scaled-up And Continuous Fluidized Beds

Coal gasification plays an important role in clean coal technology. Catalytic gasification is considered as an effective method for coal conversion especially when a high-metamorphous anthracite with very low validate (Vad<5%) is gasified. Although the catalytic gasification of high-metamorphous Fujian anthracite in a bench-scale fluidized bed has been achieved high gas yield more than 3m³/kg by previous studies, the operation ways and equipment scale need to be modified and enlarged in order to satisfy the further demand in industrial scale-up. Therefore, a suit of scaled-up and continuous fluidized bed with I.D. 123mm has been designed and set up in our lab, then using industrial sodium carbonate or black liquid as the catalyst, the catalytic gasification of Fujian anthracite has been carried out respectively in a bench-scale fluidized bed with I.D. 28mm (BSFB) and a scaled-up and continuous fluidized with I.D. 123mm (SUCFB). The effects of operation parameters, such as the additive concentration of catalyst (sodium carbonate 0%～8% or black liquid, in which the Na content is converted as the Na2CO3 content occupied in the coal weight, 0%～11.2%-Na₂CO₃ -BL-Load), the gasification temperature(820℃～900℃)and the ratio of steam to air(1.659,2.087,2.680), on catalytic gasification have been examined and compared by this study. The results are established as follows:(1) The catalytic gasification of Fujian Yongan anthracite can be performed under the following suitable operation conditions, i.e. catalyst concentration (sodium carbonate 5% , 7%-Na₂CO₃-BL-Load), gasification temperature: 850℃～880℃and steam/air≥2. In the above conditions and adding any catalyst case, either in BSFB or in SUCFB by comparing to without catalyst case, the carbon conversion enhances over 1.4 times and the gas yield rises above 1.5 times. Furthermore, the gas calorific value increases 1.5 times in BSFB and near 3 times in SUCFB, that means that later has the better catalytic effect since the more sufficient contact between gas and solids...