The leaching and kinetics of magnesium in phosphate ore slurry during FGD Process

Summary: The phosphate ore reserves in China are very large, but the overall quality is poor, and the magnesium impurity in phosphate ore is not conducive to the production of phosphorus chemical products. Recovery of sulfur dioxide from exhaust gas by phosphate slurry is a new desulfurization technology developed in recent years. During SO/sub 2/ removal from flue gas by phosphate ore slurry, in phosphate ore magnesium can be simultaneously reduced. The magnesium leaching process could be described by the reaction-controlled shrinking core model. The leaching process of magnesium from phosphate ore slurry in FGD process includes 5 steps and 10 steps, which describes a gas-liquid-solid three-phase complete reaction process of removing magnesium from industrial flue gas desulfurization of phosphate slurry. In this study, a three-phase mass transfer kinetics model was established to find the controlling factors of the desulfurization reaction rate of the magnesium removal system of phosphate ore slurry in the FGD Process, and the research showed that the gas film resistance was the key control step, the solid film resistance was negligible. The reaction relation of desulfurization and removal of magnesium from phosphate slurry was obtained as k=3.766×e-10318.39/RT. (author)