Simulation,Optimization And New System Design For Sintering Flue Gas Purification Process

The proposal of ultra-low emission requirements in the steel industry has brought new challenges to the sintering flue gas purification process.Scientifically implementing full process control and reducing sintering flue gas pollutant emissions have become an inevitable choice for china’s environmental protection and the sustainable development of the steel metallurgy industry.Due to the limitations of the existing sintering process characteristics and raw materials,the air leakage phenomenon of the sintering machine in the sintering process and the low system operation efficiency and high equipment failure rate in the terminal treatment still need to be solved urgently.Therefore,it is of great significance to optimize and develop a sintering flue gas purification process suitable for china’s national conditions,economical and efficient,and with independent intellectual property rights.First of all,in view of the problems of ammonia slip and desulfurization efficiency in the ammonia desulfurization process,this paper took the ammonia desulfurization process of a steel enterprise as the research object,and used the Aspen Plus software as the simulation platform to establish the ammonia flue gas desulfurization process model for simulation and optimization The position of ammonium sulfite oxidation and the position of ammonia replenishment were analyzed,and the influence rule of process operating parameters was simulated and analyzed,and the single tower and double tower desulfurization processes were compared and simulated.The results showed: in this system,absorption tower oxidation is a better oxidation method;when the liquid mass flow rate of supplemental ammonia was 331.28 kg/h in the absorption tower slurry tank A1,the liquid mass flow rate of supplemental ammonia was 195.3 kg/h in the absorption tower absorption section A2,the benefit of supplementing ammonia liquid was the best;the changes in operating conditions affected the efficient operation of the system,When the flue gas operating conditions changed,the system operating conditions should change accordingly;the ammonia double tower desulfurization process wasbetter than the single tower desulfurization process.In this system,the temperature of the flue gas entering the absorption section should be maintained at 50-60℃,the process make-up water should adopt the normal temperature feeding method,and the liquid concentration of supplemental ammonia should be 18%-20%.Secondly,in view of the problems of large amount of flue gas pollutant emissions and difficult control in the traditional belt sintering process,a sintering flue gas online purification with waste heat recovery system based on vertical sintering was designed.The system can realize the staged circulation of flue gas in the sintering process,online desulfurization and denitrification,and efficiently recycle the residual heat energy in sintering flue gas and the sintering material,which will solve the problem of air leakage in the traditional belt sintering process,reduce the energy consumption and the emission of pollutants during the sintering process.