赤泥的固硫特性及其机理研究  

Desulfurization characteristic and mechanism of red mud from alumina plant

作　　者：赵改菊[1] 路春美[2] 田园 樊兆燕[2] 赵建立[2] 张宗宇[1] 

机构地区：[1]山东省科学院工业节能研究中心,山东济南250103 [2]山东大学能源与动力学院,山东济南250061 [3]山东省青年干部管理学院管理科学系,山东济南250014

出　　处：《燃料化学学报》2008年第3期365-370,共6页Journal of Fuel Chemistry and Technology

基　　金：山东省自然科学基金(Y2003F07)

摘　　要：Sulfation reaction process of red mud and limestone were investigated by thermogravimetric analysis method.Phase composition of desulfurization product and calcined sample microstructure were examined by XRD,mercury intrusion porosimeter and SEM respectively.Desulfurization mechanism of red mud was discussed,which provided useful data for red mud as substitute for limestone used for coal desulfurization agents.It is shown that the possible desulphurization index of red mud is higher than that of limestone under the same condition.Calcined red mud has more middling size pores and larger specific surface areas than calcined limestone,which enhances desulfurization reaction rate.Moreover,red mud includes more ferrite and alkali metal salt compared with limestone.At low temperature they can enhances lattice defect of desulfurization agents and the diffusion ability of Ca2+ and O2-.This improves speed of surface chemical reaction and final reaction.At high temperature ferrite and alkali metal may form fused mass with dicalcium silicate together.This reduces specific surface area and porosity of red mud,thus,desulfurization activeness of red mud is weakened.Alkali earth metal carbonate may be added when red mud is used for desulfurization agents in higher temperature boiler.Sulfation reaction process of red mud and limestone were investigated by thermogravimetric analysis method. Phase composition of desulfurization product and calcined sample microstructure were examined by XRD, mercury intrusion porosimeter and SEM respectively. Desulfurization mechanism of red mud was discussed, which provided useful data for red mud as substitute for limestone used for coal desulfurization agents. It is shown that the possible desulphurization index of red mud is higher than that of limestone under the same condition. Calcined red mud has more middling size pores and larger specific surface areas than calcined limestone, which enhances desulfurization reaction rate. Moreover, red mud includes more ferrite and alkali metal salt compared with limestone. At low temperature they can enhances lattice defect of desulfurization agents and the diffusion ability of Ca^2＋ and O^2-. This improves speed of surface chemical reaction and final reaction. At high temperature ferrite and alkali metal may form fused mass with dicalcium silicate together. This reduces specific surface area and porosity of red mud, thus, desulfurization activeness of red mud is weakened. Alkali earth metal carbonate may be added when red mud is used for desulfurization agents in higher temperature boiler.

关 键 词：赤泥 固硫特性 反应机理 

分 类 号：O643[理学—物理化学]