Performance enhancement of lab scale flash evaporation desalination system with sponge demisters: A practical approach

Abstract

The current work focuses on mitigating the challenges associated with steam-carrying effects during flash desalination. Through experimental trials in a controlled laboratory setting, the impact of varying experimental parameters on the steam carrying ratio, flashing factor and separation efficiency is studied. Results suggested that the steam carrying ratio decreased with decreasing water pool height but increased with the degree of superheat and liquid entrainment. The value of the steam carrying ratio is reduced by 76.25 % by implementing a sponge inside the flash chamber at the same superheat. Liquid entrainment is significantly affected by the separation height and initial surge tank pressure. A high liquid entrainment results in a significant evaporated mass difference between experimental and theoretical results. The vapour mass transfer during the experiments without sponge arrangement is approximately two times the mass obtained from theoretical calculation. The results indicate that liquid entrainment is reduced by about 92% by incorporating the sponge at constant experimental conditions. The experimental data with sponge agree well with the theoretical results, with a maximum error of 18%. Finally, separation efficiency is proposed to compare the amount of liquid entrainment removed from total entrainment.