High-temperature evaporation of water droplets with solid impurities

Theoretically predicted characteristics of high-temperature evaporation of water droplets with solid impurities are presented. The evolution of droplet radii and temperatures during evaporation in a heated gas for their initial radii in the range 10 to 100 $\mu$m and gas temperatures in the range 500 to 1100 K is investigated. It is shown that an increase in the initial mass fraction of solid impurities in water droplets leads to non-linear increase in their evaporation rate. It is found that for the initial mass fractions of solid impurities in the range 5 to 8%, droplet initial radii in the range 10 to 100 $\mu$m and gas temperatures in the range 500 to 1100 K, droplet evaporation times increase from 0.1 to 0.36 s. These times are typical for spraying of wastewater in heating chambers.