Process optimization and crystallization kinetics of ammonium sulfate from wet ammonia‐based desulfurization

Abstract There are some problems in the production of ammonium sulfate, a byproduct of the ammonia desulfurization process, such as small crystal size and uneven distribution. The evaporative crystallization kinetics of ammonium sulfate and the factors affecting the crystallization of ammonium sulfate for improving the quality of ammonium sulfate were studied. The results showed that the largest mean diameter of ammonium sulfate was obtained at a stirring speed of 400 r/min, evaporation temperature of 60 °C, and pH of 5.0. The particle size of the ammonium sulfate increased when the crystal seed was introduced. The metastable region of ammonium sulfate was determined by laser method. The crystallization process of ammonium sulfate was studied using population balance equations and intermittent dynamic method, and the empirical equation of nucleation rate and growth rate of ammonium sulfate crystallization was obtained. This experiment can provide a solution for the problems existing in the production of ammonium sulfate in the process of ammonia desulfurization.