Study On Purification Scheme Of Coal-fired Flue Gas

With the development of society,people’s awareness of environmental protection is becoming stronger and stronger,and the introduction of ultra-low emission standards has put forward new requirements for the treatment of flue gas pollutants.Existing coal-fired unit flue gas treatment is made up of multiple devices connected in series to achieve the treatment of different pollutant components.The treatment process affects each other,making it difficult to upgrade.Therefore,simultaneous desulfurization and denitrification technologies have attracted the attention of researchers.Low temperature plasma is an effective simultaneous desulfurization and denitrification technology.In this project,the dielectric barrier discharge is used to generate the plasma.Based on the design and construction of the plasma desulfurization and denitration experimental platform,the characteristics of NO under different power supply characteristics and flue gas conditions are studied.And SO₂ conversion characteristics in the reactor,and then discuss the effects of various gas components on the conversion efficiency of NO and SO₂ in the reactor,and provide pollutant removal rules and mechanism analysis to provide technical support for the application of plasma desulfurization and denitrification.The research results show that as the voltage and energy density at both ends of the reactor increase,the removal efficiency increases rapidly and gradually tends to be gentle;when the input voltage is 60V,as the frequency increases,the removal rate increases first and then decreases.The center frequency is between 8 and 9KHz.When desulfurization and denitrification alone,the NO removal rate decreases with the increase of O₂ content and water vapor content.The SO₂ removal rate increases with the introduction of water vapor.When NO and SO₂ are present at the same time,there is a certain competitive relationship between the two,so that the removal rate of NO and SO₂ is lower than the removal rate when removed alone.The introduction of additives can improve the efficiency of flue gas treatment,at a flue gas temperature of 120-150℃,the addition of ammonia can improve the conversion rate of SO₂.For the removal of NO,NH₃ and NO can undergo a reduction reaction at low temperature（120-150℃）,the addition of NH₃ further improves the removal of NO Rate.Under the conditions of simultaneous addition of NH₃and SO₂ will promote the removal of NO.