Research And Realization Of Eliminating White Smoke From Boiler Flue Gas

In this subject,the process system and control method of white smoke plume removal from boiler flue gas are studied.Through the analysis of Gaussian smoke plume diffusion model,the formation mechanism of white smoke plume is analyzed based on the enthalpy-humidity diagram of wet flue gas,and the critical condition of no white smoke plume is studied.Based on the analysis of the factors that affect the formation of white smoke plume,and according to the two controllable factors that affect the formation of white smoke plume,the technical route and control strategy of white smoke plume treatment are studied,and the process flow and control system scheme of white smoke plume removal from boiler flue gas are determined.White smoke plume removal system,the condensation temperature of the wet flue gas is determined by analyzing the heat transfer rate and heat balance of the system under the condition of satisfying the technical index of white smoke plume removal,thus the boundary conditions of the smoke cooler was determined.Considering comprehensively the energy consumption and heat transfer area of the wet flue gas white smoke plume removal process system,Aspen Plus is applied to simulate and calculate various process parameters of the system to optimize the parameters of the wet flue gas white smoke plume removal process system.The least square method is adopted to obtain the calculation formula of wet flue gas saturation temperature and absolute moisture content through piecewise fitting,with the calculation error less than 10%.On this basis,a smoke exhaust temperature prediction model is established.Through this model,the mathematical relationship between smoke exhaust temperatures is predicted according to the external atmospheric temperature,relative humidity,atmospheric pressure and smoke condensation temperature.The control scheme of boiler flue gas white smoke plume removal process system is determined.The smoke exhaust temperature prediction model is used as the control algorithm of the system.An automatic control system with S7-300 PLC as the control core and TIA Portal as the monitoring interface is constructed.The control of flue gas emission temperature under different external atmospheric environment and flue gas condensation temperature conditions is realized,and the effect of eliminating visual white smoke plume is achieved.