Adsorption Research Of Mixed Style Calcium Oxide Adsorbing Mercury In Flue Gas

Large amounts of mercury vapor is produced from flue gas. Mercury is a kind of virulent and volatile material,it can exist in the atmosphere for a long time,which does huge damages to the environment. Because of its volatile and undissolved character,it is hard to control.At present more and more attention is paid on this issue.This paper introduces current control technology of mercury vapor in the scientific field.The paper put forward to the strategy of control mercury vapor by mixed calcium oxide.Fixed adsorption bed is a kind of important device to research adsorption performance.The paper researchs the adsorption performance by the device.First of all, production methods of mixed calcium oxide adsorbent are introduced. Sulfur and ferric chlo-ride are mixed with calcium oxide by different mass ratio,and then The experiment of removal mercury is made with active carbon and calcium oxide on the fixed adsorbent bed.Experimental results indicate that active carbon has a better adsorption performance., calcium oxide has a worse adsorption performance on the low temperature.The breakthrough curve of calcium oxide is far above that of active carbon.The adsorbent performance of calcium oxide is worse then that of active carbon ,the adsorbent quantity of mercury is also far lower then that of active car-bon.The latter is about 4 times of the former,then mixed calcium oxide adsorption experiment is made.The experimental results indicate that the mixed calcium oxide adsorption performance improve greatly.The entrance concentration of mercury vapor and reaction temperature are im-portant factors of adsorption properties.The higher the entrance concentration the more the quan-tity of mercury.the adsorption properties become worse when the entrance concentration in-crease.High temperature contributes to the mercury adsorption,as the temperature rise the quan-tity of mercury increase.Mixed calcium oxide adsorption properties and that of active carbon are compared.On the low temperature of 20℃,the adsorption properties of active carbon is almost the same as that of mixed calcium oxide,but on the high temperature of 140℃.The properties of active carbon is worse then that of mixed calcium oxide. In the end,the paper introduces several types of adsorption constant temperature line.the Langmuir and Freundlich constant temperature mathematical models are established. By using least square method to make the experimental data fitting,the theory of sorbent equilibrium ad-sorption,adsorption equilibrium constant and adsorption rate are figured out.