图书馆订购 Guest

ISSN Online: 2379-1748

ISBN Flash Drive: 978-1-56700-472-4

ISBN Online: 978-1-56700-471-7

3rd Thermal and Fluids Engineering Conference (TFEC)
March, 4–7, 2018, Fort Lauderdale, FL, USA

Nucleating agent enhanced thermal desalination at the triple point

Get access (open in a dialog) pages 739-745
DOI: 10.1615/TFEC2018.ewf.021246

摘要

An energy-efficient desalination process based on spray vacuum freezing of seawater at the triple point of seawater is developed. Freezing and vaporization of water happen simultaneously at the triple point with net-zero thermal energy consumption, both of the processes generates purified water in form of ice and vapor, correspondingly. The vapor is then compressed to a pressure above the triple point and condensed on ice to produce fresh liquid water. Since no thermal energy input is required in the simultaneous phase transition processes, the majority of energy consumption of this technology is used for vapor compression from below-triple point pressure to above it to allow condensation of vapor. The initial pressure of vapor is under equilibrium with the sprayed water droplets, the temperature of which depends on the degree of subcooling during the vacuum freezing process of the droplets. By using proper nucleating agents in seawater, the subcooling is suppressed within 1 °C of the theoretical melting point. As a result, the energy consumption for vapor compression is dramatically decreased by 83%. In addition, ice produced by spray freezing is easy to handle and transport comparing to conventional freezing desalination technologies. Applications that can directly benefit from the use of this desalination technology include seawater desalination, brackish water treatment, as well as fresh water supply for remote communities.