Patent FR-2957388-A1 (FR)
Title: Solar chimney for e.g. producing electricity, comprises solar air collector, envelope of collector, system for recovering condensation water, water diffusers, reservoir, device for evaporating water, water pump, and anti-fog system
Inventor: D ESSERTAUX JEAN MARIE
IPC: A01G9/24
Filed: 2010-03-15
Abstract: The solar chimney (4) comprises a solar air collector that is transparent to solar radiation and placed on a disc-shaped area at the center of which a cylindrical chimney lies on solid supports, an envelope (3) of the solar collector, a system for recovering condensation water dripping from exchanger, water diffusers, a reservoir, a device for evaporating water to be recycled, a water pump, a FIWIHEX(RTM: Heat exchanger), an anti-fog system, and an electric motor. A height above ground of the solar air collector is >= 10 m towards its periphery. The solar chimney (4) comprises a solar air collector that is transparent to solar radiation and placed on a disc-shaped area at the center of which a cylindrical chimney lies on solid supports, an envelope (3) of the solar collector, a system for recovering condensation water dripping from exchanger, water diffusers, a reservoir, a device for evaporating water to be recycled, a water pump, a FIWIHEX(RTM: Heat exchanger), an anti-fog system, and an electric motor. A height above ground of the solar air collector is >= 10 m towards its periphery and >= 26 m in immediate vicinity of an edge of the solar chimney. A perimeter of space defined by the solar collector and the ground is open on the outside space in the normal operating mode, and is closed by a screen having a slope of 45[deg] , where the closure takes place by raising the screen from the floor towards the outside edge of the solar air collector. The plants are grown on the peripheral part occupying up to 2/3 of the radius of the total area of solar collector. The greenhouses are built under the solar collector and are in form of tunnel or other longitudinal forms that are arranged in the north-south direction along its length and have an aluminum carrier structure outside of the plastic envelope. The greenhouses occupying the part of the area close to the solar chimney on one third radius of the solar collector are used for the evaporation of water to be recycled, for drying of agricultural products or heating of panels containing a hydrophilic product to extract water. An outer metal support structure of closed greenhouses (2) comprises metal elements for attaching a second inner structure on the vertical plane perpendicular to the length of the greenhouse, where metallic elements of the inner structure are parallel to the metal elements of the external carrier structure. The plastic envelope is thermally insulated from metallic elements, while ensuring complete sealing of the interior volume of the greenhouse, and consists of lateral parts attached with thermal insulation at the edges of the heat exchange device. The supports of the solar collector are the external structures of closed greenhouses. The closed greenhouse comprises a device constituted by elements for evaporating or ensuring productivity of plants to maintain a moderate climate in the interior space of the greenhouse. On the ground, the evapotranspiration of plants is irrigated by water that is originated from the sewage treatment plant. A part exceeding the envelope of the greenhouse comprises a double wall and an outer wall, which is made of aluminum and has a cylindrical shape. An air/liquid heat exchanger connected to heat storage tank by pipe is set vertically in the space defined by the inner wall of tower. The system for recovering condensation water dripping from exchanger is placed at the bottom of the chimney that has no wall so that the cooled air descending from the chimney spreads over the entire surface of the greenhouse whole day. The circulation of the liquid in the exchanger connected to the heat reservoir is reversed at night so that the exchanger has the function of the radiator. The reservoir contains a mixture of magnesium salt and water to reduce the volume of liquid required for the storage of heat throughout the day, and has an expansion tank on its upper part to condense the water vapor. The steam is released from the magnesium chloride water solution during the temperature rise in daytime. The water includes swimming pool water, grey water, bathroom sink water, laundry water and sea water or brackish water, and is treated by anaerobic biological treatment and ultraviolet treatment to eliminate virus or microbe and by desalination. The water evaporation device is constituted of a reservoir for receiving water to be evaporated, where a flow of pipe is controlled by a stopper. A plate made of an aluminum having flattened gutter form is fixed between towers of closed greenhouses, where the gutter has a south oriented slope for the liquid to flow through it and is made of metal. The pump is configured for pumping the water present in the reservoir to be evaporated towards the pipes positioned in the space between the top of the greenhouse and the metallic gutter. The pipes are laid parallel to the gutter and above the water diffusers integrated with pipes. The water flowing in the gutter is redirected towards the tank where it is pumped again. The additional heat exchange device is in thermal contact with the outer wall of the tower. The anti-fog system present on the inside walls of the greenhouse is constituted of a layer of liquid glass.