| The power generation in China is mostly generated by coal-fired plant. As the coal resources of high quantity of ash and sulfur, the pollution of sulfur dioxide, which produced by coal-fired power plant, has been concerned seriously nowadays. The flue gas desulfurization (FGD) is an effective way to control the emitted sulfur dioxide, and the wet FGD process is the most extensively used technology for desulfurization.The advantages of lime ammonia FGD method include the wide range of concentration of sulphur in the applyed coal, high desulfurization efficiency, no artifactitious contamination for producing and etc. Because of the chief equipment and technique are mostly imported from the abroad presently, the technology is far from mature.It is necessary to lucubrate oxidation mechanism of calcium sulfite and the main influencing factors in the oxidation of calcium sulfite, which are valuable for accelerating the oxidation Rate, consummating academic basic of lime stone-gypsum FGD and optimizing technical process.The oxidation kinetics of sodium sulfite was studied by bubbling apparatus. The macroscopic oxidation kinetics of ammonium sulfite acid was investigated via variation of pH, concentration of calcium sulfite, airflow flux and temperature. The results as follow:â‘ The general reaction rate is directly proportional to flux of airflow, when air flow is no more than 380L/h, When the value of pH was close to 5.5, higher reaction rate were obtained. The concentrated sulfite could not be oxidized rapidly.â‘¡The sulfite air oxidation is in accordance with the free radical reaction mechanism, the typical chain reaction initiator can catalyzed the reaction of sulfite and oxygen effectively, the typical radical absorbent can terminate the reaction.The instinct reaction rate for ammonium sulfite and dissolved oxygen are 1.5 response and 0 level reaction respectively.â‘¢Assumption that establish mathematical model of the working conditions for the total reaction process, which including the chemical reaction and oxygen transfer diffusion two process. Under the experimental conditions, the total rate of chemical reaction is influenced on oxygen diffusion.â‘£Manganese dioxide-hydrogen peroxide were used as the oxidizer, which can promote ammonium sulfite oxidation process effectively.On the basement of this experience, the mechanism of ammonium sulfite oxidation is studied. According to a dimensionless Hatta Number, the reactive stages are predicted by the calculation of the composition in the slurry. Making use of these foundational data of the experiment, this paper obtains each dynamic parameters that respond to each reactive stages, providing a guide line for the congeneric research.
|
PDF Full Text Request