Abstract:
The recycling of zinc sulphate, a by-product in the removal of sulfur dioxide of low concentration by zinc oxide, is an important step to affect the desulfurization process and also the key to solving the fouling and plugging of equipment pipelines caused by low oxidation rate of the desulfurization system. A novel method of ozone-enhanced oxidation process to oxidize zinc sulfite and form soluble zinc sulfate was proposed in this paper. Effect of the initial concentration of zinc sulfite, stirring speed, ozone flow rate, initial pH, and temperature on the process was investigated. The results showed that the pH of the solution increased first and then decreased during the oxidation process and the concentration of zinc ions increased linearly with the increase of oxidation time during the process. The oxidation rate increased first and then decreased with the increase of initial zinc sulfite concentration or the ozone flow rate. As the stirring speed or the initial pH increased, the oxidation rate also increased. Temperature showed slight effect on the oxidation rate. The research results provided a theoretical basis for the efficient desulfurization by using zinc oxide and the recycling of by-products.