Experimental Study On Desulfurization Technology By Flue Gas Circulating Fluidized Bed

A review on pollution and control for SO2 in flue gas is carried out in the dissertation, CFB FGD process is brought forward on the base of large number of literatures. CFB FGD installation was built in the laboratory and experimental studies were carried through systemically, influences on desulfurization efficiency of all factors were discussed. The study works have important signification to deeply understand the reacting feature of CFB FGD and seek absorbent with high desulfurization efficiency. CFB FGD designed in the laboratory is provided with the advantage of combinedinner and outer circulation,and special interior structure and type.Highly active absorbent is used in CFB FGD firstly,90% desulfurization efficiency can be achieved under optimum operating conditions. Experimental results show that operation temperature and flue gas humidity are the important parameter affecting the desulfurization efficiency.Preparation mechanism of highly active sorbent is analyzed in detail, think that fly ash as carrier of lime and unique surface characteristic of highly active sorbent have important meaning for desulfurization .Fly ash with lime hydration, fly ash without hydration and fly ash after desulfurization are taken pictures by SEM,,the changes of structure of active sorbent after hydration are approved from micro-structure.The study on mechanism of CFB FGD is carried out in the dissertation, think that absorption is main process for desulfurization, but adsorption has little contribution to desulfurization. At the same time special processes of inside CFB, such as material circulation, abrasion of inside CFB, water evaporation and so on have great influence on desulfurization.Upward flow of gas and solids in the core and the backmixing of material in the annulus are taken into account in the model, twelve hypothesizes are put forward to establish the mass transferring model.The efficiency model of CFB FGD is achieved through theoretic deduction, and the theoretical desulfurization efficiency is calculated. The theoretical results accord with the experimental results well. Operation results show that the installation is reliable and simple with low invest and running cost, study works of the dissertation provide theoretical references and practice experiences for FGD fitted the situation of our country.