Solar barometric distillation for seawater desalting Part III: Analyses of one-stage and two-stage solar vapour thermo-compression distillation technologies

The report concerns design aspects for the recently proposed solar barometric distillation technology for seawater desalting (SW–SBD) via underground barometric layout. One-stage and two-stage SW–SBD desalting plants applying a solar vapour thermo-compression distillation technology are specifically analysed. Feed brine at subatmospheric pressure is made to flow in vacuum solar collectors of simple design and construction to absorb solar radiation and to deliver the water vapour which drives a vapour thermo-compression distillation process at operative temperatures below 100°C. The proposed SW–SBD desalting technology has a good energy efficiency and promising technicoeconomic features. Field research on SW-SBD prototype plants is necessary to bring SW-SBD desalting technology to its full technological development.