Numerical Simulation Of Low NO_x Operation Optimization For A660MW Opposed Swirling Fired Utility Boiler

The low NOx combustion technology combined with SCR flue gas denitrationtechnology can make the NOx emission meet up with the state standards, but there are stillsome problems such as the denitration efficiency is low, the ammonia emissions are toohigh. Therefore, the low NOx emissions operation optimization has the practicalsignificance.First of all, in this paper it carried out the numerical simulation of the flow field, thecombustion field, the combustion products NOxemission characteristics research in the660MW Opposed Swirling Fired Utility Boiler under the rated conditions, by comparing theresults with the actual measured result, make validation that the numerical simulation ofboiler model and the boundary condition setting are reasonable, which can be used inpractical engineering.Secondly, according to the different operating conditions of the coal-fired boiler, usethe numerical simulation method to do the simulation research for boiler flue gas emissionsof NOxconcentration field. Mainly make a research of the influences of the coal millcombinations and boiler load change on the flow field, the combustion field, and thecombustion products NOxemission characteristics in the coal-fired boiler furnace.Finally, it makes the numerical simulation research of the flue gas denitration SCRsystem,with the simulation of the boiler flue gas emissions of the NOxconcentration fielddistribution, mainly simulate the NOxconcentration field distribution, the distribution oftemperature field and velocity field distribution in the connected section of the flue gasexports and SCR system, based on this result of the simulation parameters, which can beimported into the inlet of the SCR flue gas denitration system. By numerical simulation ofthe SCR flue gas system, as the structural parameters and the position of the guide plate is fixed in boiler flue gas system, adjusting the parameters of the ammonia injection system, itcan make the flue gas and ammonia mixed well and then get into the catalyst system, NOxin flue gas and the ammonia then can react well, which can achieve a good result fordenitration and reduce the ammonia escape rate.