Study On Sulfur Dioxide Absorption And Desorption Characteristics Of Basic Aluminum Sulfate Desulfurization Method

Basic Aluminum Sulfate desorption desulfurization is a kind of desulfurization technology about the absorption of SO2 in low concentration and the desorption of SO2 at high concentration in flue gas which can recover the sulfate and regenerate the desulfurization sorbent. In this paper, the research is the change rule of alkalinity, the content of aluminum and pH when the absorbed dose of SO2 changes and the influence of the desulfurization liquids absorption result by the desorption environment.The results of my research show that the gas in aluminum sulfate solution is mainly by the form of SO32- and HSO3- and a little by the form of SO42-. No matter how the alkalinity and aluminum changes in aluminum sulfate solution, when SO2 change within a certain range, the quantity of SO32- and HSO3- are always equal to the quantity of SO2gas; By the aluminum sulfate solution in same alkalinity and these in different Aluminum absorbing the equal SO2 gas, the potency of SO42- will more and more higher when the quantity of Aluminum adding. The common point is that the quantity of SO42- will be much more by keeping adding the SO2 gas. In the absorption and the desorption, the Aluminum in basic aluminum sulfate solution is constant, but alkalinity and pH will keep down when the SO2 gas adding. At the same time, the alkalinity will stop pH down. In addition, when the alkalinity is higher, the buffer action is stronger.In addition, the basic aluminum sulfate solution will absorb SO2 gas to recreat basic aluminum sulfate by heating analysis. When the desorption temperature is higher and the desorption time is longer, the desorption rate will be higher. In 98℃, the desorption rate will reach a maximum, when the desorption peocess continues, the desorption rate will be low, at last it is constant; In the same conditions, with the help of the stirring machine the SO2 desorption rate will be stimulative. In the process of the absorption and desorption SO2, some SO32- will become SO42- by oxidation and then SO32- will lose the ability of heating desorption, what’s more, some unknown factors which have an influence on raising the desorption of SO2 will be studied in the further...