Design and Simulation of a Low-Temperature Thermal Desalination System

The prototype of a low-temperature thermal desalination system treating 2500 L day-1 of saline water was designed thermally and geometrically, to be integrated with a vacuum spray flash drum and spray nozzles, a plate heat exchanger-type condenser, and a thermosyphon solar water heater to produce potable water for a small community. The design bases were the feed flow rate, the feed temperature from 45 to 65 & DEG;C, the salinity of 0.035 kg kg-1, and the vacuum drum pressure from 2 to 6 kPa absolute. The estimated yield of potable water based on the simulated droplet dynamics was in the range of 68.91-75.80 %. The plate heat exchanger and the thermosyphon solar water heater were designed for effective condensation and passive heating, respectively. A low-temperature thermal desalination system based on the spray-assisted vacuum flash operation was designed with the passive heating of saline water and effective condensation of water vapor. The flash drum was designed effectively by simulation of the droplet dynamics. A corrugated plate heat exchanger and a thermosyphon solar water heater were designed to optimize the system. image