Precipitation And Retention Mechanism Research Of Bromide In Coal-fired Process

With China’s rapid economic development, while energy consumption is also growing, including in particular the consumption of coal, it was decided China’s lean oil, less gas and rich in coal. However, coal is a "dirty" energy. Coal contained in S, N, F, Br, Hg, Se when coal combustion that they will be discharged into the atmosphere. Worldwide each year due to coal combustion emissions into the atmosphere is approximately 199500 tons of bromine. Bromine of coal was experienced chemical reaction, to Br, HBr and Br2 forms of escape. People’s health will be heart, if huam being at the atmosphere of HBr concentration of 5mg/m’. Therefore, there is every reality and positive significance that resach on bromine of coal.In this paper was based on the research scholars to study the bromine content and occurrence situation of coal. By constructing the simplex method of experiment, I was experimental studies of bromide ion selective electrode method to measure the factors in the process of bromine. By statistical and neural network of data processing method, I was analysied the processing of electrode measured bromide the mian affecting factor of iodide. By high temperature hydrolysis-ion selective electrode method, changing the amount of oxygen, residence time and combustion temperature during coal experimentally studied the precipitation mechanism of bromine, experimental study of coal during the precipitation mechanism of bromine. According to these work, it was result that the amout of precipitation of coal bromine was gradually increase when-increasing reaction temperature, residence time and increase the amount of oxygen. However, at a temperature of 1273K, retention time 40min and O2 in the amount of 150ml/min, the amount of precipitation of coal bromine is essentially the same. It was precipitation in the form of HBr. Through theoretical of Quantum Chemistry and Thermodynamics, had been analyses and other studied of CaO solid bromine reaction mechanism. By studying, we know that coal-fired process CaO reacts with HBr CaBr2 reaction is spontaneous.With the increasing temperature, CaO-HBr reaction became contravariantly finite. It is disadvantage to CaO-HBr reaction. Therefore, CaO-HBr reaction temperature was range 973K from 1073K.The results show that un-reacted shrinking core model can be used to describe the chemical reaction of CaO-HBr bromine retention macro-kinetics, forecast the reaction temperature, HBr gas concentration and effects of chemical reaction of CaO particle size. CaO conversion increases with the increasing of HBr gas concentration, and compared with the effect of reaction temperature, the effect is more obvious. With the decrease of the initial particle size of CaO, significant improvement of CaO concentration rate and had a significantly impact on the rate of bromine retention.