Development, Calculation and Experimental Study of a Heat Pump for Vacuum Water Distillation Systems

Abstract

One of the most promising methods of water purification and distillation is the evaporation method using heat pump energy transformers. The article describes the developed scheme of a heat pump for vacuum distillation, which operates under atmospheric pressure with water at saturation temperatures in the range of 20–40 °C. Results of experimental studies on a specially made installation are presented. The proposed technical solution using a two-lobe Roots type vacuum compressor pump as the basic means of increasing the pressure is shown to be viable. A mathematical description of the unsteady heat and mass exchange process of a single-stage distillation unit with mechanical vapor compression was verified. An equation for calculating the heat transfer coefficient for evaporation of water under vacuum in a free volume on vertical pipes is proposed. Data on the performance and power consumption of the installation were obtained.