Vapour compression distillation incorporating multi-phase water ejector

This study considers a mathematical model for a single effect, thermo vapour compression desalination unit that utilizes high pressurized water ejector. The model developed has been used to investigate the performance single effect water ejector vapour compression unit different operating conditions. Many parameters have been considered in this study, the geometry of the ejector, the state of motive water, evaporator temperature, temperature drop across the evaporator and pressure loss. In this analysis the effect of the above parameters on the streams properties inside the ejector is obtained, such as, the entropy creation across ejector, minimum mixing temperature inside ejector mixing section, motive water to product flow ratio, and specific energy required for such system. This study been also extended to include the steam ejector system. Similar to water ejector, the different parameters affecting the performance of the steam ejector are studied. A comparison is done between the water ejector, and steam ejector to study their performance the same operating conditions and geometry. It was found that the water ejector is superior to steam ejector in terms of lower energy consumption per unit product, in addition to utilizing water instead of live steam which could be very beneficial specially in remote areas where a steam source would be difficult to obtain. 4.36 figs., 45 refs