Numerical simulation of wet deacidification process of sludge incineration flue gas.

• A deacidification model was build considering the evaporation process of droplets. • The removal of SO 2 is inhibited by HCl during wet deacidification. • The content and distribution of deacidifier in the droplet were predicted. Deacidification is an indispensable process when cleaning the sludge incineration flue gas. To ensure the flue gas meets the emission standard, guarantee the long-term stable operation of the purification system, and provide theoretical basis for the combined operation of different deacidification methods in the future, a numerical simulation model based on the Euler-Lagrangian method is established to study the wet flue gas deacidification process by using the computational partical fluid dynamic software—Barracuda. The mass transfer process between gas phase and droplets is considered by using the two-film theory, and the effects of evaporation from droplets and vapor condensation in the flue gas during wet deacidification are considered. The model is verified by comparison with experiments, and the calculation results considering the evaporation and condensation process are closer to the experimental results. Besides, the competition mechanism of HCl and SO 2 during the deacidification process and the influence of different operation parameters on the deacidification efficiency are analyzed; the detailed distribution of different substances in the deacidification tower are obtained. The removal efficiency increases when stoichiometric ratio (SR), droplet velocity, and spray angle increased; the removal efficiency decreases when droplet size increased. The results have important guiding significance for the optimization and design of flue gas deacidification tower. [ABSTRACT FROM AUTHOR]