Research On CFD Simulation Of Multi-pollutant Collaborative Control Device In Coal-fired Power Plants

With its fast economic growth, China’s energy demand, especially electricpower, is greatly increased. The coal-dominated energy structure in Chinadetermines the long term priority situation of coal in China’s energy stage. As coalaccounts for a highly percentage of power resources in china, the burden ofcoal-fired power plants pollution control is getter harder.At present, the single pollutant control is adopted to management of pollutantemissions in coal plants. Typical techniques, such as the electrostatic precipitatorsand bag filter for the dedust, limestone-gypsum wet flue gas desulfurization, theselective catalytic reduction of denitration and Activated carbon injection formercury absorption have been widely used at home and abroad. However, the largeoccupation of land and the high cost of equipment and running are the disadvantagesof these methods. Under this background, the multi-pollutant collaborative controldevice in coal-fired power plants emerges. Based on the Integration of coal-firedflue gas circulating fluidized bed desulfurization to take off the mercury andmultiple cooperating pollutants purification technology research and demonstration(863), and taking the flue gas circulating fluidized bed desulfurization towermatched a300MW unit in a thermal power plant as a complete set of model, thearticle proceeded with the CFD analog computation in earlier stage of technologydemonstration projects in order to achieve the guidance for the engineeringapplication. Meanwhile, the article explored the chemical reaction process of theoxidant, absorbent and flue gas inside the tower shell of the circulating fluidized bed.On the basis of oxidant mixed in the original moisture, this article made the frontoxidant premixed device model and analog computation to the mixture of oxidizingagent and flue gas. Results showed that oxidant in flue gas through premixed device has a better distribution than that with the means of directly injecting oxidant to themoisture. At the same time, this way can increase duration of exposure betweenoxidizing agent and flue gas, realizing a more sufficient chemical reaction in thetower, so as to improve the efficiency of collaborative removal equipment.