RU2412909C1 - Desalination installation - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to an installation for desalinating sea water and can be used in hot climate regions using solar energy to heat water, as well as on submarines and ships. The desalination installation has a source of water, a source water pump, a source water heat exchanger-heater, a centrifugal-vortex steam generator, a steam condenser, a condensate storage container with outlet pipes. The source water heater is in form of a heating container which receives solar energy through focusing reflectors or lenses. The water inlet pipe of the centrifugal-vortex steam generator is connected to the heating container through a circulation pump. The water outlet pipe of the centrifugal-vortex steam generator is also connected to the heating container, forming a closed circulation system.

EFFECT: low power consumption, creation of high vacuum, provision for water deep cooling, high efficiency of desalination.

6 cl, 5 dwg

Description

The invention relates to the field of energy and chemical technology (water distillation for food and technological purposes). It can be used in countries with hot, dry climates using solar energy, as well as on long-distance vessels, submarines using electric or thermal energy.

Thermal desalination plants are known in which the source water is heated and evaporated in evaporators due to steam passing through the heating surfaces. Next, the resulting steam is condensed and desalted distilled water is obtained (see P. D. Lebedev, A. A. Shchukin “Heat-using Installations of Industrial Enterprises.” - M .: Energy, 1970, Fig. 2-3, p. 95). The disadvantage of these installations is the insufficient quality of distilled water due to the fact that the process of heating the water is combined with the evaporation process, and with the formed steam, droplets of water containing salts and other impurities are carried away.

Thermal desalination plants are also known in which the source water from a source of unlimited volume (for example, sea) containing salts and impurities is heated in the source water heater (heat exchanger) below the boiling point at a steady pressure in the heater, then the water is driven through a centrifugal vortex steam generator (CVP), in which the pressure decreases, the water boils and part of the water evaporates, being cooled by lowering the pressure and boiling point (the process of separate sequential heating of water and mating). Chilled water is discharged into a source of unlimited volume. The resulting vapor, devoid of impurities during centrifugal-vortex evaporation (centrifugal forces drop water droplets back into the water stream and steam is separated), is fed into the cooled demineralized water storage tank, which is also the condenser of the formed steam (hereinafter referred to as the condenser). The capacitor is under the vacuum created by the vortex vacuum pump (water-jet vortex ejector). Condensate is desalinated (distilled, desalinated) water, ready for consumption for food and technical purposes (see Magazine "Inventor and Rationalizer" No. 11 of 1976, pp. 7-9.) This installation is adopted as a prototype.

The prototype has disadvantages:

1. The suction pipe of the vacuum pump (ejector) is connected to the steam generator through a capacitor-condenser. To drain distilled water from a condenser tank, it must be installed at a height exceeding the height of the vacuum (if the vacuum is 0.6 kgf / cm ² (6 m water column), then the tank is installed at a height above 7 meters). At a lower installation height, it will not be possible to drain distilled water from it.

2. The vortex vacuum pump has an efficiency two times lower than a conventional water-jet ejector, and can create a vacuum of about 4-5 meters of water column (while a water-jet ejector - 9.9 m water column). Under vacuum, 5 m water. St. water boils at a temperature of 80.86 ° C, which requires a high temperature for heating the source water (above 85 degrees). Water can be cooled by evaporation only up to 80.86 ° C. Then it merges back into a source of unlimited volume (at sea) at high temperature. Part of the heat transferred to water in the heat exchanger disappears (low efficiency of heat exchanger heat utilization).

Vacuum desalination plants require a deeper vacuum and recirculation of the hot water passed through the DHW back to the heater.

3. The drain pipe of the evaporated water (residue) from the central heating unit is also under vacuum, which requires the central heating unit to be installed at a certain height and does not allow the central heating unit to be installed in a low room, for example, in a submarine or ship.

The aim of the present invention is the desalination of sea water (any mineralized water) in areas with a hot climate by using solar energy to heat water, as well as providing the possibility of desalination of sea water in submarines and ships.

This goal is achieved by the fact that in the well-known desalination plant containing a source of source water, a source water pump, a heat exchanger-heater of the source water, a centrifugal vortex steam generator with inlet and outlet pipelines of the source water and with a discharge steam line, a steam condenser, a storage tank of distilled water ( desalinated water, condensate) with a discharge pipe of distilled water, connecting pipes of the source water, the source water heater is a heating tank a spruce that receives solar energy through focusing reflectors or lenses or through heating surfaces from an alternative energy source, and the pipeline supplying water to the central heating circuit is connected to the heating tank through a circulation pump, and the water discharge pipe from the central heating circuit is also connected to this heating tank, and all together (tank, pump, pipeline, CVP, pipeline, tank) form a closed circulation system, in addition, a pipe that exhausts steam from the CVP is connected to the suction pipe of a water-jet ejector, input present in the vacuum system and to ensure condensation of vapors obtained RJC and removal of distilled water (distillate condensate).

The closed system for ensuring vacuum and condensation of vapors obtained in the central water supply center and distilled water drainage contains a working water tank (BRV), a working water circulation pump (TsNRV), a water-jet vapor ejector-condenser connected to the pump discharge pipe and the drain pipe with BRV, a cooler working water installed on the drain water pipe after the ejector, the pipeline for water withdrawal from the BRV.

The upper super-liquid part of the source water heater tank is connected by the breathing pipeline to the central heating unit, and the pipeline has a shut-off and regulating body (valve, valve, valve).

The centrifugal vortex steam generator (CVP) contains the main body in the form of a shell (pipe section) with upper and lower end caps, with a tangential nozzle for supplying the source of heated water, with holes in the lower part of the housing, with a cyclone separator, in the upper part of which there is a lower part of the main body with openings, and a steam exhaust pipe passing through the main body, and in the lower part there is a tangential water outlet pipe.

The circulation pump supplying water from the heating tank to the central heating unit has a water recirculation pipeline from the discharge pipe to the suction pipe, with a nozzle at the end placed in front of the pump impeller, or a water-jet ejector is installed on this recirculation pipe, the suction pipe of which is connected to the heating tank .

Capacity-heater 3 has a purge pipe (discharge into the sewer partially evaporated water).

Figure 1 shows a diagram of a desalination plant using solar energy.

Figure 2 - diagram of a desalination plant using alternative energy (electrical, thermal, mechanical) in a low room (for example, in a submarine or ship).

Figure 3 - diagram of the pump (item 10 of figure 2) using an anti-cavitation device in the form of a nozzle at the end of the water recirculation pipe installed in front of the impeller of the pump.

Figure 4 - diagram of the desalination plant using anti-cavitation device for the pump 10 in the form of a water-jet ejector.

Figure 5 is a longitudinal section of a centrifugal-vortex steam generator (CVP) (as the CVP taken "Deaerator-heat and mass exchanger" centrifugal-vortex type, protected by RF patent No. 2131555).

Desalination plant has: 1 - source of source water (sea, lake, pool); 2 - source water pump; 3 - a tank-heater of the source water (the tank must have a shape that can withstand external atmospheric pressure up to 9 meters of water column); 4 - the pipeline of source water supplied to the tank 3 through a heat exchanger 5 (working water cooler); 6 - bypass pipe in addition to the heat exchanger 5; 7 - devices directing the energy of the sun's rays to the tank-heater (focusing mirrors, lenses), 8 - a spare heater from an alternative energy source (for example, an electric heater); 9 - water level regulator in the tank 3; 10 - pump for supplying heated water from the tank 3 to the centrifugal-vortex steam generator of the central heating unit; 11 - purge pipe for draining concentrated brine from the tank 3 (to maintain a certain salinity of water in the tank 3); 12 - centrifugal-vortex steam generator CVP with inlet - 13, outlet - 14 water pipelines and steam line 15 (CVP must be installed at a height of 6-8 m above the water level in tank 3, for example, on a column or tower); 16 - a water-jet steam ejector-condenser with a supply 17 and a discharge - 18 pipelines of working water, which is used as a condensate formed from steam (can be installed on the same column (tower) as the central heating unit); 19 - suction pipe of the ejector, on which the vacuum gauge 20; 21 — purge water heat exchanger in pipelines 4 and 11; 22 - tank of working water (condensate) with pipelines 23 - condensate drain and 24 - tank emptying; 25 - circulation pump for working water; 26 - storage (consumption) tank of condensate (desalinated, desalinated water), 28 - purge pipe; 29 - a perforated pipe (disperser) at the end of the pipe 14, placed in the upper part of the tank 3. 30 - a breathing pipe connecting the upper space of the tank 3 with the central heating unit with a shut-off regulating body (valve) 31 (installed with insufficient room height when the central heating unit is installed directly above the tank 3, see figure 2); 32 - pipeline recirculation of water from the discharge pipe of the pump 10 to the suction pipe with a nozzle 34 at the end of the pipeline in front of the impeller 35 of the pump 10 (Fig.3). In figure 4, as an anti-cavitation device, a water-jet ejector 36 is used instead of the nozzle 34.

The centrifugal-vortex steam generator shown in Fig. 5 has a cylindrical body 37 in the form of a pipe segment with upper 38 and lower 39 ring caps, with a tangential pipe 40 for supplying superheated water, with windows 41 (or short tangential pipes), with an annular partition 42 ( a washer), with a pipe 43 connecting the CVP to the tank 3 with the help of the breathing tube 30 (Fig. 2), a pipe 44 for removing steam from the CVP. Below the windows 41 there is a cyclone 45 (steam separator from water), in the lower part of which there is a tangential pipe 46, which discharges water into the tank 3 through the pipe 14.

The operation of the installation (figure 1) is as follows. The source water from the source of source water (sea) is pumped into the tank 3 by the pump 2 (when filling the tank 3 through the bypass pipe 6 and the level controller 9). When the unit is operating, pipeline 6 is closed, and the source water is supplied to the central heating unit through pipeline 4 and the heat exchanger 21 and level regulator 9. The sun's rays are directed to the walls of the tank 3 using focusing mirrors 7 (an alternative energy source for heating water can be used at night, as well as on ships and submarines). The water in the tank 3 is heated (for example, up to 80 ° C). A pump 10 is included in the operation, which circulates water from the tank to the steam generator 12 (CVP). Then, through the pipeline 14, back to the tank 3. In the water cooling system, the water acquires a rotational motion, and the water pressure drops to a value below the boiling point (for example, to 0.2 at, when the boiling T is 59.76 ° C). The generated steam is sent to the steam line 15, and the water, cooled by vaporization to 59.76 ° C, is sent back to the tank 3. The concentration of salts in the tank 3 increases, since the steam is discharged without salts. In order to maintain a constant salinity in the water of the tank 3, part of the water is discharged through the purge pipe 11 through the heat exchanger 21 into the sewer.

The CVP should be installed at a height of 10 meters so that chilled water flows by gravity into tank 3 (for example, on a column or tower. See figure 1). Steam is sucked off by the ejector 16 through the suction pipe 19 and condenses due to contact with the working water of the ejector. Working water is heated by condensation of steam. It passes through a heat exchanger 21 (working water cooler), is cooled and discharged into the working water tank 22. From the tank 22 by the pump 25, the working water is sent again to the ejector 16. The amount of working water in the tank 22 increases due to the condensate obtained from the steam. Tank 22 is initially filled with drinking water. In the process, all the working water in the tank 22 becomes condensate due to steam condensation. Excess condensate (desalinated water) is discharged through a drain pipe 23 (a water withdrawal pipe from the BRV) into a flow tank 26 and is disassembled by consumers. Source water passing through the heat exchanger 5 cools the working water and heats up a little. Part of this water is sent to the tank 3 through the heat exchanger 21 and regulator 9 (in addition to the bypass pipe 6), and part of the water is drained into the sewer or back to the sea via the pipe 27. During operation, the water in the tank 3 evaporates, and the salts remain in the tank. The concentration of salts increases. To maintain a constant concentration of salts in the tank 3, purge (discharge of part of the water into the sewer) through the purge pipe 11. To use the heat of the purge water, it is passed through the heat exchanger 21 before being discharged into the sewer.

The installation can work both in continuous mode and in periodic mode. If the power of the heaters corresponds to the capacity and the temperature of the water in the tank 3 is kept constant, then the installation can work continuously. If the thermal power of the solar reflectors is less than the power of the steam generator, then the water in the tank 3 should be heated to maximum and start the installation. The temperature of the water in tank 3 will gradually drop and approach the boiling point at a given vacuum. The operation of the installation is carried out in periodic mode. A solar-powered installation can operate continuously during the day, and in the evening and at night until the water in tank 3 is cooled or switch to an alternative energy source.

The work of the CVP is as follows. Superheated above boiling point, the water enters the housing 37 through the tangential pipe 40, acquiring a rotational movement. A vertical rotating water level is set. The pressure of the rotating flow of water drops from the periphery to the center, the water boils. Through the windows 41, water and steam flows into the cyclone 45. The steam leaves the CVP through the pipe 44 to the ejector 16, and the remaining water flows through the pipe 46 to the tank 3. The pipe 43 and pipe 30, with the valve 31 partially open, provide a vacuum in the tank 3 (slightly smaller than in the DPC). The difference in vacuum (the difference in absolute pressures in tank 3 and in the central heating unit) creates conditions when the water in tank 3 does not boil and boils in the central heating unit.

The installation in the embodiment of FIG. 2 is characterized in that the DPC does not have the ability to be installed at a sufficient height (for example, the installation is on a submarine or ship). The circulation of water between the tank 3 and the central heating unit (12) is carried out by the pump 10. Using a breathing tube 30 and a shut-off regulating body (valve) 31, a vacuum is established in the tank 3. To avoid cavitation of the pump 10 operating under vacuum, a water recirculation pipe 32 with a nozzle 34 (see Fig. 3) or an ejector 36 (see Fig. 4) is installed.

The presence of a heater tank connected to a centrifugal-vortex steam generator (CVP) using pipelines and a circulation pump, with the formation of a closed circulation system, provides great savings in thermal energy, since the water discharged from the CVP is heated much higher than the source (in the prototype, insufficiently cooled water was immediately discharged into a source of water of unlimited volume - into the sea (equivalently - into the sewer) and cold source water came into its place).

The connection of the steam outlet pipe from the CVP to the suction pipe of the water-jet ejector allows the ejector to become a condenser and install it at a low height, which the submarine or ship can provide (in the prototype, the coder, which is under vacuum, must be at the height of the created vacuum to drain condensate from it (distillate)).

The presence of a water-jet steam ejector-condenser and the connection of its suction pipe to the steam line from the CVP creates a deeper vacuum than the vortex vacuum pump, which provides deeper cooling of the water entering the CVP and the formation of more steam.

The use of steam distillate (condensate) as working water for the ejector and the presence of a working water cooler (5) on the distillate pipe simplifies the design of the installation (due to the lack of vacuum in the distillate circulation system, which is the working water of the ejector and the need to install the distillate tank at a height determined by vacuum).

The connection of the upper supra-liquid part of the tank - the source water heater with the breathing pipe to the CVP and the installation of a shut-off regulating body (valve, tap, valve) on this pipe allows the heater tank to be placed under a certain vacuum and to ensure free drainage of water from the CPU to this tank (partially using dynamic pressure of a rotating stream of water in a water-heat pump).

The presence of a recirculation pipeline between the discharge and suction nozzles of the circulation pump and the nozzle at the end of this pipeline in front of the impeller of the pump, or the presence of a water-jet ejector on this recirculation pipe, the suction nozzle of which is connected to the heater tank, can prevent cavitation of the pump 10 under vacuum in the tank 3 and in the pipeline in front of the pump 10.

The presence of a purge pipe at the heater tank allows you to minimize the amount of purge water with the maximum amount of salts, which will reduce heat loss.

Claims (6)

1. Desalination plant containing a source of source water, a pump of source water, a pipeline of source water, a heater of source water, a centrifugal-vortex steam generator (CVP) with a supply pipe of heated water, with a discharge pipe of water from the CPU, with a steam pipe that removes steam from the CPU, circulating connecting water pipes, a steam condenser, an accumulating capacity of condensed steam (distillate, condensate) with a distillate discharge pipe, characterized in that the capacity of the source water heater is a heater that receives the energy of the sun through focusing reflectors or lenses or through heating surfaces from an alternative energy source, the pipeline supplying water to the DPC connected to the heater tank through a circulation pump, and the water drainage pipe from the DPC is also connected to this heater tank, and all together (tank, pump, pipeline, CVP, pipeline, tank) form a closed circulation system, in addition, a pipe that exhausts steam from the CVP is connected to the suction pipe of a water-jet ezhek a torus, which is part of the system for ensuring vacuum and condensation of vapors obtained in the central heating unit, and drainage of distilled water (distillate, condensate). 2. Desalination plant according to claim 1, characterized in that the closed system for providing vacuum and condensation of vapors obtained in the central water supply center and distilled water outlet contains a working water tank (BRW), a working water circulation pump (TsNRV), a water-jet vapor ejector-condenser connected to the discharge pipe of the pump and the drain pipe with BRV, a cooler for working water installed on the drain pipe of water after the ejector, a pipe for taking water from the BRV, and the tank of working water is a desalinated water accumulator (disti lyata condensate). 3. Desalination plant according to claim 1, characterized in that the upper super-liquid part of the source water heater tank is connected by a breathing pipeline to the central heating unit, and the pipeline has a shut-off and regulating body (valve, valve, valve). 4. Desalination plant according to claim 1, characterized in that the centrifugal vortex steam generator (CVP) contains a main body in the form of a shell (pipe section) with upper and lower end caps, with a tangential nozzle for supplying the source of heated water, with holes in the lower part case, with a cyclone-separator, in the upper part of which is located the lower part of the main body with holes and a steam exhaust pipe passing through the main body, and in the lower part there is a tangential water outlet pipe. 5. Desalination plant according to claim 1, characterized in that the circulation pump supplying water from the heating tank to the central heating circuit has a water recirculation pipe from the discharge pipe to the suction pipe with a nozzle at the end located in front of the pump impeller, or on this recirculation pipe a water-jet ejector is installed, the suction pipe of which is connected to the heater tank. 6. Desalination plant according to claim 1, characterized in that the tank-heater has a purge pipe.

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