Experimental Investigation On Acid Gases Removal Using Circulating Fluidized Bed Reactor

The acid gases removal method of this research is a low temperature,dry process that utilizes a circulating fluidized bed reactor and calcium-based sorbents. The reactor integrates inside solids recycle with outside solids recycle,which makes it high recycle ratios and a excellent reactor. When it is used to acid gases removal,there will be high removal efficiency and sorbent utilization efficiency.A pilot-scale circulating fluidized bed reactor was modified to simulate a circulating fluidized bed reactor acid gases removal process. The contents of this research were to:investigate acid gases (SO2,HC1) removal efficiency using different sorbents (Ca(OH)2,CaO,CaCO3);investigate the influence of basic operating parameters such as approach-to-saturation temperature,Ca/(S+0.5Cl) molar ratio,velocity of void bed,inlet sulfur dioxide concentration on acid gases capture. Based on the experimental investigation,the results were used to design a new flue gas cleanup pilot-scale CFB reactor,and were referenced to industrial practices.The experiment showed that the reactor had advantages of simplicity,high efficiency,and high sorbent utilization. Under all experimental conditions,sulfur capture by Ca(OH)2 varied between 50 and 99.3%,sulfur capture by CaO varied between 32.2 and 92.2%,chloride hydrogen capture by CaO varied between 77.5 and 93.8%,and chloride hydrogen capture by CaCO3 varied between 74.3 and 91.7%;Among theinfluence parameters to desulfurization process using Ca(OH)2,the sequence of importance was approach-to-saturation temperature,calcium-to-sulfur ratio,velocity of void bed,and inlet sulfur dioxide concentration respectively;Sulfur capture by CaO was lower than Ca(OH)2.The experiment also showed that hydrogen chloride removal process using CaO was similar to that using CaCO3;Hydrogen chloride capture by CaO was a little higher than CaCO3. It showed that hydrogen chloride removal process was easier than desulfurization process,and reactor temperature had greater influence on desulfurization than on hydrogen chloride removal.