Simulation On The Uniformity Of SCR Entrance Flow Field And Study On The Sonic Soot Blowing

It is the world’s biggest fossil fuel consumption for our country, especially the coal fuel consumption of coal-fired power plant has been in the top few. Coal burning discharge nitrogen oxide(NOX) can not only form nitric acid rain, but the main pollutants of photochemical smog and ozone hole, and nitrogen oxides also cause the injury to person, ecological environment, social and economic damage. One of the most widely used to control NOX emissions is the selective catalytic reduction(SCR). This method use the catalyst to promote the reducing agent(H2, CO, hydrocarbons, NH3) and NOX in the tail gas of coal combustion to react to water and N2, the exhausted tail gas is clean without pollution. But it may produce catalystvoid ash, ash blockage, even the catalyst poisoning, serious when replacing the catalyst directly increased plant denitrification costs, and may cause the plant shutdown main tenance affects the normal power supply, causing the other major economic accidents seriously.This paper first detail analysis the components of flue gas in coal-fired power plant and the flue gas in the dynamic mechanism of the catalyst of the ash. On the bases, in order to eliminate the SCR catalyst dust, ash clogging, catalyst poisoning and other phenomena, the SCR entrance flow fields were simulate computational fluid dynamics software Fluent. Analysis of the effect of several different forms of flow guide plate to flue gas flow through the corner. Use the direct draw rectifier grid forms required in Gambit software compared with the porous media model, analysis its true extent. Finally the simulation results show adopts the arrangement of 10 pieces of equal arc guide plate can, effectively improve the inlet corner of SCR reactor’s low-speed and return phenomenon; The flow equalization effect is too ideal to applicant a porous medium model to simulation the rectification grid, not better than the grid direct drawn, it’s more authentic and more convincing. So adding rectifier grid in each corner and in front of the catalyst, use pretreatment software directly draw it, it can make the flow field uniformity achieved before reaching the catalyst layer, and prevents the formation of bulk ash effectively. Some scattered clearing ash application of sonic soot blower to clear, the forth chapter through visualized analysis, detailed forecast the effect of the sonic soot blowing soot blower.