The COOSW project tests a seawater desalination system based on vacuum distillation at PLOCAN

By May 11, 2022 November 28th, 2022 News

The transnational cooperation project to develop a solution that saves energy and water in coastal facilities through devices that capture ocean energy (COOSW) is testing COOL STEAM technology, a seawater desalination system based on vacuum distillation, at the Oceanic Platform of the Canary Islands (PLOCAN).

COOSW project lead researcher Pedro Arnau, together with Professor Asier Ibeas from the Autonomous University of Barcelona, the project manager of PLOCAN’s Innovation Unit Silvia Hildebrandt, and Joaquín Serrano from the board of directors of the Spanish Research Agency announced the project tests that are being conducted in an experimental facility at PLOCAN’s headquarters in Taliarte.

COOSW is a cooperation project between Mexico (UNAM), Dominican Republic (PUCMM), Germany (FRAUNHOFER) and Spain (UAB, PLOCAN, CIMNE), coordinated by the International Centre for Numerical Methods in Engineering (CIMNE) of which PLOCAN is a partner. The project aims to develop a solution that harnesses natural resources such as the temperature gradient of the water column and wave energy to desalinate seawater and to cool small-scale coastal facilities.

The COOSW solution combines three different technologies: a WEC (wave energy converter) device is used to pump cold seawater from the deepest layers of the ocean; this cold water is then used by SWAC (seawater air conditioning) technology to cool the air; and finally, the temperature gradient between the cooler pumped water and the warm water produced by the SWAC is used in the desalination process using COOL STEAM technology.

The test being carried out at PLOCAN focuses on COOL STEAM technology, which is a multi-stage vacuum distillation desalination system, with an electrical energy requirement of less than 1.7 kWh/m3, and which utilises the temperature gradient between waters obtained with WEC and SWAC technologies.

The vacuum distillation technology evaporates water at a lower temperature, reducing the heat input required for evaporation, and has been developed by observing natural processes such as the evaporation and condensation that occurs in clouds. The process removes dissolved gases from the water beforehand to promote more efficient heat transport between stages and increase condensation.

Proyectos PCI2019-103376, PCI2019-103406 y PCI2019-103581  financiados por MCIN/AEI /10.13039/501100011033. This work was supported by the ERANET-LAC project which has received funding from the European Union Seventh Framework Programme (ERANet17/ERY 0168).