Numerical Simulation Study On Optimization Of Flow Field In Sintering Flue Gas Ammonia Desulfurization Tower

The development of the iron and steel industry is related to the foundation of my country's national economy.Sintering is an important part of the iron and steel industry,and its sulfur dioxide emissions account for one-half of the total exhaust gas emissions.The flue gas produced by sintering is a difficult point in the treatment of the steel industry because of its high moisture content,large temperature changes,high dust concentration and high pollutant content.Development of my country's sintering flue gas desulfurization technology,reduction of SO₂ emissions in the sintering process,and promotion of energy conservation and emission reduction in the iron and steel industry are major issues that need to be solved urgently.This paper establishes a gas-liquid two-phase fluid dynamics model in the ammonia flue gas desulfurization tower,and uses CFD software to perform single-factor and multi-factor simulation analysis on the process dimensions and structural parameters of the desulfurization tower.The single factor influence analysis of the flue gas inlet angle,inlet area,height from the inlet to the slurry surface,and liquid-gas ratio on the desulfurization tower is carried out.The results show that the influence of each parameter on the uniformity of the flow field and the pressure loss inside the desulfurization tower has a nonlinear relationship.Each single factor has an optimal value range;the uniformity of the flow field in the tower first increases and then decreases with the flue gas inlet angle.If the flue gas inlet angle is too large or too small,the flow field in the tower will be disturbed to a certain extent.When the inlet angle is 9°and 12°,the gas-liquid mass transfer effect is the best;when the inlet area is small,the wall flushing phenomenon is serious due to the increase of the flue gas velocity.With the increase of the area,the expansion effect of the inlet on the flue gas will change.Good,the gas-liquid two-phase interaction is more complete;flue gas and spray liquid have different meeting positions with the change of inlet height,and the gas-liquid mass transfer effect is also changed;spray liquid has obvious effect on the resistance in the desulfurization tower.The contact area of the two-phase liquid increases with the increase of the liquid-gas ratio,and the mass and heat transfer between the phases is more smooth;however,too large liquid-gas ratio will also cause agglomeration between the droplets,which will affect the desulfurization efficiency.The multi-factor analysis of the desulfurization tower shows that the flue gas inlet angle,the height of the inlet from the slurry surface and the insertion depth of the exhaust pipe have different degrees of interaction on the pressure loss and the standard deviation of the characteristic surface velocity.The optimal structure predicted by the response surface was re-modeled,meshed and flow field analyzed.The results showed that the pressure loss was reduced by 86 Pa compared to the prototype,the characteristic surface velocity standard deviation value was reduced by 0.102 m/s,and the flow field in the tower was more To be uniform is conducive to the improvement of desulfurization efficiency.This shows that the response surface method has a certain degree of reliability in the structural optimization of the desulfurization tower,and the research results can provide a basis for the actual industrial design of the desulfurization tower.