Abstract:

China encourages “nearly zero discharge” of industrial wastewater, and advanced treatment of brine is of great deep concern. Desulfurization wastewater, mining wastewater and other industrial wastewater can be processed by spray evaporation technologyat ambient temperature. On the selfbuilt outdoor test beds for spray evaporation test, the evaporation rate of brine was measured and the characteristics of evaporation products were described by scanning electron microscope (SEM). Smaller atomized particulars lead to a larger evaporation rate. When the particle diameter is over 500μm, decreasing the size of particular has small effect on evaporation rate. Smaller salinity leads to a larger evaporation rate, but the difference is slight. The spray evaporation rate has an approximately linear positive correlation with the wind velocity, exponential positive correlation with temperature, and a negative correlation with the relative humidity. The wind velocity is the decisive factor of the spray evaporation rate as wind velocity is large. When the relative humidity is over 90%, humidity is the decisive factor. When the temperature is less than 15℃, the temperature is the main factor . The mechanical atomization rate of the test is about 4～12 times of natural evaporation rate.At the same time, it is noted that there is wind loss in spray evaporation rate, and measures should be taken to avoid the secondary pollution caused by water of high salinity. 

Key words:

spray evaporation;mechanical atomization, desulfurization wastewater, brine, desalination, nearly zero discharge, evaporation rate