Modelling and experiments on ocean thermal energy for desalination

A new desalination system based on ocean thermal energy (OTE) is presented in this paper. It introduced the basic model and the system was studied experimentally. The desalination process consists of flash evaporation, condensation and seawater transportation. Here, OTE was used to maintain a vacuum, under which liquid could be evaporated at atmospheric temperatures and with less energy than conventional technique. The experimental platform is a pilot-scale system and the freshwater production could reach 100 kg/h, compared with 20 kg/h of Kumar's study in 2007. Meanwhile, a new type of equipment was presented which could improve the performance of the experimental system. At last, the effect of various operating conditions (temperature of surface and deep seawater, mass flow and freshwater production) was studied experimentally and compared with theoretical results. The results agreed well with the theoretical predictions. It was found that the effect of temperature difference was significant on the desalination system.