Novel Solar Crystallizer for Water Desalination with Zero Liquid Discharge Accepted by EST!
2018-09-12 11:41:54Wang group8
Solar Evaporator with Controlled Salt Precipitation for Zero Liquid Discharge Desalination
Abstract: A sustainable supply of clean water
is essential for the development of modern society, which has become
increasingly dependent on desalination technology since 96.5% of the water on
Earth is salt water. Thousands of desalination plants are producing massive
waste brine as byproduct and the direct discharge of brine brings serious
concerns about its ecological impact. The concept of zero liquid discharge
(ZLD) desalination is regarded as the solution but the current ZLD technologies
hampered by their intensive use of energy and high cost. In this work, a 3D cup
shaped solar evaporator was fabricated to achieve ZLD desalination with high
energy efficiency via solar distillation.
It produces solid salt as the only byproduct and use sunlight as the only
energy source. By rationally separating the light absorbing surface from the
salt precipitation surface, the light absorption of the 3D solar evaporator is
no longer affected by the salt crust layer as in conventional 2D solar
evaporators. Therefore, it can be operated at an extremely high salt
concentration of 25 wt% without noticeable water evaporation rate decay in at
least 120 hour. This new solar evaporator design concept offers a promising
technology especially for high salinity brine treatment in desalination plants
to achieve greener ZLD desalination as well as for hypersaline industrial
wastewater treatment.
