Study on the evaporation performance of concentrated desulfurization wastewater and its products analysis

Concentrated desulfurization wastewater evaporation technology exhibited significant superiority in desulfurization wastewater zero discharge. Nevertheless, changes of physical and chemical properties of the concentrated wastewater shifts evaporation mode during wastewater evaporation, which may cause difficulty in disposing of evaporation products. In this work, the rotary spray drying pilot test experimental platform was utilized to investigate the evaporation performance of concentrated desulfurization wastewater. The results indicate that, while the evaporation rate of concentrated wastewater is lower than that of non -concentrated wastewater, its lower free water volume resulting in the improved evaporation performance. Increasing the inlet flue gas temperature, gas -liquid ratio, and prolonging the residence time of flue gas can promote droplet evaporation. Besides, the evaporation products were analyzed by various characterization techniques. The elemental composition and particle size of concentrated wastewater evaporation products change. At a moisture content of 2 %, the Flowability Function is 3.57 (2 < FF < 4), indicating a cohesive nature and poorer flowability compared to the non -concentrated wastewater.