Optimization Characteristics Of Flow And Mass Transfer Coupled In SDA Desulfurization Tower

Spray drying technology(SDA)is an effective desulfurization method.In the process of desulphurization,it is easy to scale when the absorbent is in contact with the tower wall,which affects the distribution of air flow in the tower,hinders the full contact between slurry and flue gas,and reduces the chemical reaction rate and desulphurization efficiency.Based on the RNG k-? turbulence model and the multiphase flow model,the simulation of the gas,liquid two-phase flow field,and the movement of the particles under the operating parameters are obtained.Trajectory,flow field characteristics,evaporation characteristics,and product wall distribution characteristics can also be studied.By optimizing the structure and operating parameters of the tower,the problem of the resultant wall is improved.The flow field in the SDA desulphurization tower is composed of the flue gas of the upper and lower flue,and the distribution of the upper and lower air flow is uneven during the operation,which makes the flue gas in the core reaction zone of the tower is not insufficient contact with the slurry.Therefore,by installing a damper at the upper flue,the proportional distribution of exhaust from upper and lower flues can be adjusted and airflow structure altered,which can mitigate the scaling issue in the desulfurizing tower.The results show that the efficiency of the desulfurizing tower inside is higher than 95% on the condition that the width of the board baffle is 2250 mm,meeting the production requirements.Meanwhile,there is the minimum amount of scale formed on the wall of the desulfurizing tower,which is suitable to conduct production.The droplet diameter and flue gas temperature of the slurry are important factors that affect the desulfurization efficiency and slurry fouling in the desulfurization tower.Therefore,the process of slurry evaporation with the diameter of 30-70 ?m in the desulfurization tower is simulated numerically.The results show that the droplet diameter is 50?m,which is a kind of operating parameter which ensures the desulfurization efficiency and the least scaling amount at the same time.Optimization study is carried out for the working conditions of flue gas temperature of 110-150°C.Results: When the temperature of the flue gas is 130 ° C,the scale is the least,and it is suitable for continuous production.Through the above research,the optimal desulfurization operation parameters are determined,and the scaling phenomenon of the tower wall can be improved,so that the SDA desulfurization tower can be operated more continuously and stably,and a solution for achieving the energy-saving and emission reduction and protecting the environment is provided.