The Study On Technical Transformation Plan Of Denitration System In Coal-fired Power Plants

The harm of nitrogen oxides(NO_x)is one of the important environmental issues that need to be solved in today's society.Coal-fired power plants are the main source of nitrogen oxides(NO_x).To effectively control the emission of nitrogen oxides(NO_x)from coal-fired power plants,the study on flue gas denitration becomes more important.Coal-fired power plants should do their best to do a good job of denitration construction.Based on a large number of references and on-the-spot participation in the operation of coal-fired units in operation,through comprehensive analysis of various real-time monitoring data on the site,it is finally confirmed that the factors affecting ammonia depletion rate and denitration efficiency of denitration in power plants are flue gas flow and temperature,ammonia injection,nitrogen oxide concentration,flue gas pressure,etc.And the methods of improving operation stability and economic of SCR denitrification system are derived from these laws.Meanwhile,a physical model of the SCR denitrification system is established by the use of computational fluid analysis software.In the flue path bend and the inlet of SCR reactor,some different types of deflector are designed.Numerical simulation based on the calculated parameters of the full-load conditions is conducted.By the analysis of simulation results and observing the diversion effect of the various deflector types,the type,number,and structure of the preferred deflector for the denitrification system can be chosen.In order to research the SCR denitrification catalyst performance,the design of small hot reaction test bench is presented in this paper.It is based on the site survey of a 350MW domestic coal-fired power plant,which is proposing a denitration reforming concept and carrying out a practical application design,including low NO_x combustion technology upgrade,combustion operation optimization,SCR technology transformation,reducing agent preparation and so on,which is to achieve NO_x emissions up to standard discharge(less than 200mg/Nm~3).The design of denitration transforming is a kind of global design of the SCR denitrification,which has high reference walue.The design has a large design margin,which is adapting to new coal-fired power plants,and to old plants as well.Therefore,it is suitable for most of coal-fired power plants,and has broad application prospects.