Patent DE-102007055448-A1 (DE)
Title: Solar distillation plant for extracting clean fresh water from dirty primary water such as salt and brackish water, comprises housing closed with translucent cover, evaporation surface, medium circulation circuit and distillate container
IPC: C02F1/14
Filed: 2007-11-19
Abstract: The solar distillation plant (1) for extracting clean fresh water from dirty primary water such as salt and brackish water, comprises a thermally insulated housing (2) closed upwardly with a translucent cover (8), an evaporation surface (12) present in the housing, a medium circulation circuit having lines for transporting a liquid medium to be distilled, where the lines have openings for guiding the medium on the evaporation surface, and a container (20) for collecting distillate of the medium in the housing. The evaporation surface is aligned on the cover. The solar distillation plant (1) for extracting clean fresh water from dirty primary water such as salt and brackish water, comprises a thermally insulated housing (2) closed upwardly with a translucent cover (8), an evaporation surface (12) present in the housing, a medium circulation circuit having lines for transporting a liquid medium to be distilled, where the lines have openings for guiding the medium on the evaporation surface, and a container (20) for collecting distillate of the medium in the housing. The evaporation surface is aligned on the cover so that solar energy passing through the cover arises on a top side of the evaporation surface. The evaporation surface is formed from a non-insulated, heat conducting material so that the energy is supplied back to the top side of the evaporation surface during the condensation of the medium at the lower surface of the evaporation surface. The difference of the air volumes above and below the evaporation surface is maximally 10%. A condenser arrangement (18), by which the circulation circuit is led, is arranged: in the upper area of the housing below the evaporation surface; in the lower area of the housing adjacent to the lower edge of the evaporation surface; in the housing above the evaporation surface; and in the lower area of the top side of the evaporation surface. The housing is formed from a fiber-reinforced plastic tub with integrally inserted insulant. The cover has an insulating glass pane. The top side of the insulating glass pane is roughened for reducing the reflection and is coated with silicon dioxide. The inner side of the lower windowpane lying in a vacuum area is coated with a silver-containing coating. The upper area of the evaporation surface adjacent to the condenser arrangement is thermally insulated. The evaporation surface is arranged in the form of steps and has step surfaces sequentially arranged in the distance from each other so that it partially overlaps the sequential step surfaces. The rear edges of the step surface are connected with the overlapping front edge of the step surface by a connecting plate. The evaporation surface is formed from a metal sheet. Condensate run-off grooves are arranged at the lower surface of the cover projecting into the housing and laterally conveys the distillate of the lower surface of the cover. A flow control valve is intended in the circulation circuit and is controllable as a function of the temperature in the housing so that a reduced flow of the medium takes place at less temperature and an increased flow of the medium takes place at higher temperature.