RU2185327C2 - Solar distiller - Google Patents

Abstract

FIELD: solar energy technology, particularly, solar power plants converting solar energy into heat for desalting of mineralized (sea water, saline water) waters. SUBSTANCE: solar distiller has a body with transparent partition, bath, condensate accumulator, device for filling of mineralized water and discharge of concentrated brine. Installed inside solar distiller body, at its rear wall with clearance relative to wall, is vessel provided with devices for filling and discharge of mineralized water with reflecting screen mounted in front of vessel. EFFECT: increased productivity of solar distiller due to utilization of steam energy in its condensation for heating of mineralized water in vessel and also due to increased area of cooling of steam-air mixture and steam condensation. 1 dwg

Description

 The technical solution relates to solar engineering, in particular to solar installations that convert solar energy to heat for desalination of saline (sea, salt) water.

 Known solar desalination plant, comprising a housing with an inclined light-transmitting partition (glass or film), a bathtub and a condensate collector (for the closest analogue, see B.M. Achilov et al. Solar desalination plants and refrigerators. Publishing House "FAN" Uz. SSR, Tashkent, 1976, p. 15 ... 16).

 The disadvantage of this device is its low performance.

 The purpose of the proposed technical solution is to eliminate this drawback.

 This goal is achieved by the fact that in the well-known solar desalination plant containing a housing with a light-transmitting partition, a bath, a condensate collector, a device for filling mineralized water and draining concentrated brine, a container equipped with filling and draining devices is installed inside the housing at its rear wall with a gap to it mineralized water, and a reflector screen is mounted in front of the tank.

 The essence of this technical solution is to use the energy received from the Sun, which went to the evaporation of mineralized water, for pre-heating the mineralized water in the tank with the subsequent supply of heated water from the tank to the bath for evaporation. In this case, a reflector screen is used to preserve the influx of solar energy to the bath and to prevent heating of the tank from solar radiation.

 The water in the tank is heated by using the latent heat of condensation of water vapor from the vapor-air mixture. The steam-air mixture is cooled on the walls of the tank, the steam condenses, and the water in the tank is heated.

 The performance of the proposed desalination plant compared with the prototype increases both due to the beneficial use of steam energy when it is condensed to heat mineralized water in the tank, and due to the increase in the area of cooling of the steam-air mixture and condensation of water vapor (the surface of the tank is added). At the same time, unproductive losses of thermal energy by radiation from a mirror of mineralized water in the bath are reduced due to the installation of a reflector screen in front of the tank.

 Due to the constant automatic replenishment of the desalination tank with mineralized water to a predetermined level, it became possible to fill the bath with less water, which reduced the time of its initial heating and desalination operation. In this case, the water entering the bath is preheated in the tank due to steam condensation, i.e. due to the secondary use of absorbed solar energy.

 The stock of heated mineralized water in the tank by the end of daylight when it is drained into the bath provides night operation of the desalination plant and an additional condensate outlet.

 Thus, the proposed desalination plant works effectively not only during the day, but also at night.

 Automatic supply of mineralized water from the tank to the bath during daylight hours is ensured by the fact that when the level of mineralized water in the bath falls below a predetermined value, it is possible to access the air tank.

 The proposed solar desalination is shown in the drawing.

 The desalination unit includes a housing 1 with a light-transmitting partition 2, a bathtub 3 with thermal insulation 4, a device for pouring mineralized water into the bathtub and draining concentrated brine 5, a condensate collector 6, a reflector screen 7, a container 8 with refueling devices in a mineralized water tank 9 and her plum 10.

 Bath 3 may include thermal insulation 4 and may be entirely made of thermally insulated material.

 The tank 8 is executed and installed in the desalination plant so that condensate formed on the surface of the tank is discharged into the common condensate tank of the desalination plant.

 The mineralized water refueling device 9 includes a funnel, a flexible hose and an inner tube for air drainage during refueling, and the drain device 10 includes a throttle washer.

 The work of the proposed desalination plant proceeds in the following way.

 At the beginning of daylight, the concentrated brine is drained from the bath 3 using the device 5. The tank 8 is refilled through the funnel of the refueling device 9. At the same time, mineralized water enters the bath 3 through the drain device 10 and the throttle washer contained in it.

 After refueling the tank 8 (the fact of refueling is determined by the decrease in the rate of decrease of mineralized water from the funnel), the bath 3 is refilled through the funnel of the device 5 and the final refueling is completed through the funnel of the refueling device 9 to the required level. After refueling, the level of mineralized water in the bath and funnel of device 5 is the same.

 The funnel of the refueling device 9 is lowered into the mineralized water of the funnel of the device 5 to a depth that determines the level of mineralized water supported in the desalination plant in the bath 3.

 Solar radiation enters the desalination plant through the light-transmitting partition 2, heats the mineralized water in the bath 3 and evaporates it. The reflector screen 7 increases the flow of solar energy to mineralized water and eliminates its contact with the side surface of the tank 8.

 Vapors of mineralized water are condensed on the light-transmitting partition 2, the inner walls of the housing 1 and the walls of the tank 8. Due to the heat of condensation, the saline water is heated in the tank 8. The formed condensate flows into the condensate collector 6.

 As water evaporates from the bath 3, its level decreases both in the bath and in the funnel of the device 5.

 Through the gap between the wall of the funnel of the filling device 9 and the mineralized water in the funnel of the device 5, air will begin to flow into the tank 8, and the mineralized water from the tank 8 will drain into the bath 3. In the bath 3 and in the funnel of the device 5, the level of mineralized water rises and closes the gap between the funnel wall of the filling device 9 and water.

 The air stops flowing into the tank 8, and the supply of mineralized water from it to the bath 3 is stopped. Under the action of evaporation, the level of mineralized water in the bath starts to decrease again and the process of maintaining the level is repeated. While in the bath 3 enters the heated water from the tank 8.

 At the end of the day, the funnel of the filling device 10 is removed from the funnel of the device 5 and rises up. When this air through the filling device 9 enters the tank 8, and all heated mineralized water is discharged into the bath 3.

 At night, the desalination plant operates on the energy of mineralized water obtained by daytime heating of water in the tank 8 from condensing steam. Heated water evaporates, its vapors condense on the light-transmitting partition 3 and the inner walls of the housing 1, and the resulting condensate flows into the condensate collector 6.

 Thus, the proposed desalination plant works both day and night, and in it the energy received from the Sun is reused to heat the saline water supplied to the desalination from steam condensation.

 The expected increase in productivity of the proposed desalination plants compared with the prototype by 45 ... 50%.

 In this case, the estimated costs of manufacturing newly introduced funds will be approximately a quarter of the cost of the prototype.

 It follows that the implementation of the proposed technical solution is economically viable.

Claims (1)

 A solar desalination plant comprising a housing with a light-transmitting partition, a bathtub, a condensate collector, a device for pouring mineralized water and draining concentrated brine, characterized in that a container equipped with charging and draining mineralized water devices is installed inside the housing at its rear wall with a gap to it, and a reflector screen is mounted in front of the tank.