A multi evaporator desalination system operated with thermocline energy for future sustainability

摘要: Abstract All existing commercial seawater desalination processes, i.e. thermally-driven and membrane-based reverse osmosis (RO), are operated with universal performance ratios (UPR) varying up to 105, whilst the UPR for an ideal or thermodynamic limit (TL) of is at 828. Despite slightly better UPRs RO plants, all practical plants available, hitherto, operate only less than 12% TL, rendering them highly energy intensive unsustainable future sustainability. More innovative methods must be sought meet needs sustainable these should attain upper bound about 25 30% TL. In this paper, we examined efficacy a multi-effect distillation (MED) system thermocline from sea; proven technology that can exploit narrow temperature gradient 20 °C year round created between warm surface cold-seawater depths 300–600 m. Such (ST)-driven MED system, simply called ST-MED process, has potential achieve 2 folds improvement in efficiency over methods, attaining 18.8% limit. With major input emanated renewable solar, truly “green desalination” method low global warming potential, best suited tropical coastal shores having bathymetry 300 m more.