WO2001072639A1

WO2001072639A1 - Water desalting apparatus

Info

Publication number: WO2001072639A1
Application number: PCT/JP2001/002784
Authority: WO
Inventors: Yuzo Narasaki; Ichiro Kamiya; Naoyuki Inoue; Kiichi Irie; Toru Tokumaru; Tomoyuki Uchimura; Motoyasu Sato
Original assignee: Ebara Corporation
Priority date: 2000-03-31
Filing date: 2001-03-30
Publication date: 2001-10-04
Also published as: AU2001244680A1

Abstract

A water desalting apparatus which comprises a controlling device which, when the electric power generated by a source such as a solar cell is reduced, stops the supply of electric power to individual motors according to the predetermined preferential ranking so as to maintain smooth operation; a raw water flow rate controller which controls the flow of the raw water supplied to an evaporating device so that a heating medium supplied to an evaporating device has a given or lower temperature; and a concentrated raw water storage tank for storing a raw water concentrated by generating steam and a stored amount measuring device for concentrated raw water for measuring the amount of the concentrated raw water in the concentrated raw water storage tank, wherein the concentrated raw water is used as the cooling water for use in a condenser for the steam from the raw water and, when the stored amount of the concentrated raw water is lower than a given amount, raw water is supplied in advance to the evaporating device by the raw water supplying device and the raw water having been passed through the evaporating device is supplied to the concentrated raw water storage tank so that a given storing amount is maintained. The water desalting apparatus can be appropriately controlled in accordance with the conditions wherein it is operated and be used for desalting with good efficiency.

Description

Description Desalination equipment

Technical field

The present invention is a self-contained desalination method that uses solar energy and other heat sources to obtain fresh water (distilled water) from raw water such as seawater, salt-containing groundwater (brine water), and industrial wastewater by evaporation and condensation. The present invention relates to an apparatus, and particularly to a desalination apparatus provided with a control device.

Background art

Conventionally, this type of desalination apparatus includes a solar heat collector, an evaporator, a raw water supply pump for supplying raw water to the evaporator, and a heat medium connected to the evaporator and the solar heat collector to circulate a heat medium. A heat medium circulation pump for using the heat medium heated by the heat collector as a heat source of raw water in the evaporator, and condensing to receive and condense water vapor generated in the evaporator from the evaporator to form distilled water. The system is equipped with a device, a freshwater drainage pump for discharging manufactured freshwater, a concentrated raw water discharge pump for discharging raw water that has been heated and evaporated in the evaporator, and a vacuum pump for vacuuming the inside of the evaporator. These various pumps and electric devices such as electric valves provided in the supply / discharge flow path of the raw water / the discharge flow path of the fresh water are provided by attaching power supply equipment including solar cells to the desalination apparatus. Usually, they can operate independently without relying on external power.

Conventionally, such power supply equipment usually includes a battery and a charge controller for preventing overcharging of the battery, and the generated power is charged through the charge controller. The DC output charged in the battery is supplied to a DC drive electric device such as an electric valve or an AC drive electric device such as a vacuum pump via a DC transformer or a DC Z AC converter.

However, if the above-mentioned power supply equipment using a battery is used, it is necessary to install not only a battery but also a charge controller and the like, thereby increasing initial costs. In addition, the life of a battery such as a lead storage battery is shortened if it is over-discharged, so it is necessary to take countermeasures for over-discharge, such as increasing the size of the battery. Also, charge and discharge Repeatedly reducing the storage capacity of the battery requires maintenance such as replenishment of the battery fluid and replacement of the battery.

In order to avoid the problem of providing the above battery, in consideration of the fact that desalination equipment can be operated only when there is solar radiation, in the power supply equipment using solar cells, if no battery is provided, It is conceivable to stop energizing the electric equipment and stop the operation of the desalination plant.

However, in such a desalination plant, many electric switching valves are used.If the sun suddenly goes down and the power generation capacity suddenly stops, the electric switching valves cannot be closed. There is a problem that the vacuum is destroyed. Also, in such a desalination plant, when the power generation capacity was suddenly lost and the concentrated raw water discharge pump and fresh water discharge pump were suddenly stopped, multiple evaporators were connected in a multi-effect relationship. In a desalination plant equipped with a multi-effect cycle-based evaporator, the raw water supplied before the above stoppage does not discharge to the outside even if it flows down from the upper evaporator to the lower evaporator. In some cases, the raw water that has flowed into the freshwater tank may cause problems such as contamination of the freshwater.

Also, in such a desalination plant, if the amount of raw water is too small relative to the amount of solar radiation, the temperature of the heat medium will increase accordingly, and the heat collection efficiency of the solar heat collector will decrease. There is also a problem that over-concentration occurs due to evaporation. Also, if the amount of raw water is too large relative to the amount of solar radiation, there is also a problem that the raw water is not sufficiently heated, and the desalination capacity of the device is reduced.

On the other hand, in the above-mentioned conventional desalination apparatus, as the cooling water used in the condenser to condense the generated steam, generally, raw water before being supplied to the desalination apparatus is used, or巿 Water was used. However, in a desalination plant that uses raw water as cooling water, there is a problem that the cooling water temperature rises and the desalination capacity decreases as it operates2. In addition, when water or the like is used as cooling water, it is necessary to provide a cooling water supply Z replenishing means, which raises costs and requires maintenance.

In order to solve such problems, attempts have been made to use concentrated raw water, which is evaporated in the desalination plant, as cooling water for the condenser before discharging and discarding it. is there. In this case, the above-mentioned problems such as the case where the raw water before being supplied to the desalination unit is used as the cooling water are resolved, but the operation of the desalination unit is started, and the concentrated raw water is sufficiently discharged. In the meantime, there is a problem that the cooling water of the condenser is insufficient, and in the worst case, there is no cooling water at all.

The present invention has been made in view of the above points, and has as its object to provide a desalination apparatus provided with a control device for performing proper operation. Disclosure of the invention

That is, the present invention relates to a desalination apparatus, comprising: a solar heat collector; an evaporator including a plurality of evaporators, and the plurality of evaporators connected in a multiple effect relationship; and an evaporator and a solar heat collector. A heat medium circulating circuit circulates a heat medium between the evaporator and the heat medium heated by the solar heat collector to generate heat from the raw water in the evaporator. A condenser for receiving steam from the lowermost evaporator of the evaporator and condensing it into distilled water; a vacuum device for reducing the space in the evaporator of the evaporator to an atmospheric pressure or less; and a desalination device. A power supply circuit including a power supply such as a solar cell for supplying electric power for driving an electric device such as the vacuum device, and an electric power supply to the electric device when a power generation amount of the power supply falls below a predetermined amount. , Prioritize and stop Providing desalination apparatus characterized by having a device. According to this desalination apparatus, it is possible to appropriately cope with the desalination apparatus when the amount of power generation is reduced, thereby preventing the occurrence of trouble due to the decrease in power generation.

Examples of the electric equipment include, in addition to a vacuum device, a freshwater discharge pump for discharging distilled water produced by a condenser and a concentrated raw water discharge pump for discharging the concentrated raw water. When the power generation amount detection device detects that the power generation amount by the power supply has decreased to a predetermined amount or less, the power supply to the control device and the vacuum device is performed by the fresh water discharge pump and the concentrated raw water. It is preferable to stop the pump before the drain pump. This is to maintain the operation of the freshwater discharge pump and the concentrated raw water drainage pump as much as possible so that serious problems such as freshwater pollution do not occur.

After stopping the power supply to the vacuum device, the power generation amount is updated by the power generation amount detection device. When it is detected that the concentration of the raw water is reduced, it is preferable to stop the power supply to the fresh water discharge pump before the concentrated raw water discharge pump. Maintaining the operation of the concentrated raw water discharge pump is important to prevent freshwater contamination from the concentrated raw water.

The power supply may be a solar cell, and the power generation amount detection device may be a pyranometer for detecting the amount of solar radiation or a small solar cell provided separately from the solar cell. The electric equipment includes an electric open / close valve used in a supply / discharge flow path of raw water, and the electric open / close valve is preferably an electric valve that is mechanically closed when power supply is stopped.

The present invention also provides a solar heat collector, an evaporator, a raw water supply device for supplying raw water to the evaporator, and a heat medium circulating between the evaporator and the solar heat collector. A heat medium circulation circuit for using the heat medium heated by the heater as a heat source of raw water in the evaporator; and a condensate for receiving and condensing water vapor generated in the evaporator from the evaporator to form distilled water. A heat medium temperature detector for detecting a temperature of a heat medium entering the evaporator from the solar heat collector; a raw water flow controller for controlling a flow rate of raw water supplied from the raw water supply device; A control device is provided that controls the flow rate of raw water supplied to the evaporator by the raw water flow controller and controls the temperature of the hot soot supplied to the evaporator to a predetermined temperature or lower than a predetermined temperature. And a desalination apparatus. According to this desalination apparatus, efficient heating can be performed by controlling the temperature of the heat medium.

The controller controls the raw water flow controller such that when the temperature of the heating medium supplied to the evaporator is equal to or higher than a predetermined temperature, the raw water flow supplied to the evaporator always keeps a predetermined minimum flow. Is preferred.

The raw water flow controller is an electric valve, and the control device is configured such that, even though the electric valve is at a predetermined opening, the raw water flow supplied to the evaporator is equal to or less than a predetermined value. It is preferable to judge that the raw water is cut off and stop the operation of the desalination plant.

Further, the present invention provides a solar heat collector, an evaporator, a raw water supply device for supplying raw water to the evaporator, and a heat medium circulating between the evaporator and the solar heat collector. A heat medium circulation circuit for using the heat medium heated by the collector as a heat source of raw water in the evaporator; and a heat medium circulation circuit for receiving water vapor generated in the evaporator from the evaporator and condensing it into distilled water. A condenser, a concentrated raw water storage tank for storing concentrated raw water that is supplied from a raw water supply device, passes through the evaporator, is heated and generates steam to be concentrated, and stores concentrated raw water in the concentrated raw water storage tank. A concentrated raw water storage amount detector for detecting an amount of the concentrated raw water, wherein the condenser is configured to use the concentrated raw water in the concentrated raw water storage tank as cooling water for the condenser; Before operation, based on the output of the concentrated raw water storage amount detector, if the storage amount of the concentrated raw water is equal to or less than a predetermined amount, the raw water is supplied to the evaporator in advance by the raw water supply device, and the raw water passed through the evaporator. The concentrated raw water storage A desalination apparatus is provided, which is provided with a control device for controlling the storage amount to the predetermined amount by supplying the storage amount to a tank. According to this desalination apparatus, it is possible to avoid a situation in which the concentrated raw water is not sufficiently condensed at the start of the operation due to insufficient concentrated raw water.

Specifically, a concentrated raw water storage tank is provided in the condenser, and a concentrated raw water discharge pump that supplies concentrated raw water from the evaporator to the concentrated raw water storage tank is provided.The raw water is supplied to the evaporator before the desalination unit is operated. It is preferable to supply the concentrated raw water to the concentrated raw water storage tank by operating the pump, and to adjust the storage amount of the concentrated raw water. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram showing an example of the overall configuration of a desalination apparatus according to the present invention.

FIG. 2 is a diagram showing an example of a detailed configuration of a part of the desalination apparatus according to the present invention.

FIG. 3 is a diagram showing a detailed configuration example of a part of the desalination apparatus according to the present invention.

FIG. 4 is a diagram showing a configuration of a power supply facility of the desalination apparatus according to the present invention. Preferred embodiments of the invention

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 4 show a desalination apparatus using solar energy according to an embodiment of the present invention. That is, the present desalination apparatus according to this embodiment includes the solar heat collector 1 and the steam collector. It consists of a generator 2, a cooling tower 3, a distilled water tank 4, a concentrated water tank 5, and a vacuum device 6 such as a vacuum pump 6-2.

The solar heat collector 1 is composed of a plurality of solar heat collecting panels 1 — 1 to 16 that heat the heat medium with solar energy. The heat medium vapor heated by the solar heat collector 1 is sent to the evaporator 2 through the pipe 7, and the condensed heat medium from the evaporator 2 is stored in the buffer tank 9 through the pipe 8, and further, the buffer tank From 9, the heat medium circulating pump 26 and piping 10 return to the solar heat collector 1 and circulate. At the heat medium outlet of the solar heat collector 1, a heat medium temperature detector 31 for measuring the temperature of the heat medium (heat medium vapor) is provided.

The evaporator 2 has a degassing chamber 2-1 at the top, and a plurality of evaporators (here, eight evaporators 2 to 2 to 8 to 9) are located below it. It is configured. For example, raw water (in this case, seawater) W supplied from a water source such as a raw water tank (not shown) that can always supply raw water at or above atmospheric pressure is preheated through a raw water preheating pipe 12, and the deaeration chamber 2-1 Supplied to The raw water W overflowing the deaeration chamber 2-1 passes through an overflow pipe 13 and a predetermined amount of raw water W is stored in each of the first evaporator 2-2 to the eighth evaporator 2-9 in sequence. It is gradually concentrated and finally stored in the concentrated water tank 5 through the overflow pipe 14. Raw water W is supplied using a raw water supply pump 11. The flow rate of the supplied raw water W is controlled by a motor-operated valve (solenoid valve) V8. The raw water flow rate is detected by a raw water flow rate detector 32. In the example shown in the figure, the case where the pump 11 is used for supplying raw water is shown, but even without such a pump, the inside of the desalination apparatus is kept at atmospheric pressure by depressurizing the inside of the desalination apparatus with the vacuum apparatus. Raw water can also be supplied into the equipment.

The heat medium vapor from the solar heat collector 1 passes through the heat exchanger 2-1a disposed in the degassing chamber 211, and flows between the raw water W stored in the degassing chamber 2-1. The heat exchange is performed, and further, the heat exchange is performed between the raw water stored in the first evaporator 2-2 through the heat exchanger 2-2a disposed in the first evaporator 2-2. . The steam W a evaporated by heating the raw water in the first evaporator 2-2 is sent as a heat source to the heat exchanger 2-3 a in the second evaporator 2-3 through the steam pipe 15, and between the water and the raw water. Heat exchange takes place. Third evaporator 2-4 The steam W a evaporated by heating the raw water in the evaporator 2-8 is also sent as a heat source to the heat exchanger of the next evaporator, where it exchanges heat with the raw water, and is condensed with distilled water. Finally, it is stored in the distilled water tank 4.

The concentrated raw water in the concentrated water tank 5 is sent to the lower tank 3-1a of the condenser 3-1 of the cooling tower 3 through the concentrated raw water flow control valve V6 and the pipe 27 by the concentrated raw water discharge pump 16. It is supplied to the sprinkling nozzle 3-1 c by the concentrated raw water circulation pump 17 and is sprinkled as cooling water on the condensation (heat transfer) pipe 3-1 b. The water vapor Wa evaporated by heating the raw water in the eighth evaporator 2-9 in the final stage is sent to the condenser pipe 3-1b in the condenser 31 through the pipe 18 to be condensed with the concentrated raw water sprinkled. Heat is exchanged between the two and condensed to form distilled water, which is sent to the distilled water tank 4 through the pipe 19. The concentrated water overflowing the lower tank 3-1a is discharged through the concentrated water discharge pipe 20.

A concentrated raw water storage amount detector 34 for detecting the concentrated raw water storage amount is provided in the lower tank 3-1a of the condenser 3-1. Also, the concentrated water overflowing the lower tank 3-1a is discharged through the concentrated water discharge pipe 20.

The vacuum device 6 includes a gas-liquid separator 6-1 and a vacuum pump 5-2 connected to the gas-liquid separator 6-1. The gas-liquid separator 6-1 is connected to the pipe 21 through which the heat and soot from the solar heat collector 1 passes through the pipes 21, 22, 23. The degassing chamber 2-1 of the evaporator 2, the condenser 3-1 Connected to header 3 — 1d. As a result, the evaporating space of the evaporator 2, the condensing space communicating with the evaporating device, and the distilled water storage space can be reduced in pressure as described later in detail.

Further, the distilled water Wb in the distilled water tank 4 is supplied to a predetermined place by a distilled water pump 25. In FIG. 1, V1 to V8 are valves. These valves use electric valves that automatically close mechanically when the drive voltage drops. This is to prevent the vacuum break by mechanically closing the valve when the driving voltage using the solar cell as a power source drops, as will be described in detail later.

FIG. 4 is a diagram showing the configuration of the power supply equipment of the desalination apparatus according to the present invention and the control unit thereof. Reference numeral 41 denotes a solar cell, and a DC output generated by the solar cell 41 is input to a DC transformer 42 to be boosted. DC transformer 4 2 is connected to DC transformer 4 2-1 and constant current The constant voltage means 42-2 maintains the output voltage of the DC transformer 42 at a predetermined constant value, the amount of power generated by the solar cell 41 increases, and the DC transformer 42-1 Even if the output voltage of the power supply becomes overvoltage, it protects the subsequent electrical equipment: The output of the DC transformer 42 is input to the DC / AC converter 43 and converted to AC (three-phase AC). This AC output is supplied to the raw water supply pump 11, concentrated raw water discharge pump 16, distilled water pump 25, concentrated raw water circulation pump 17, and heat medium circulation pump 26 via drivers D 1 to D 6 The power is supplied to an AC drive electric device such as a blower fan 3-2, and is also supplied as a power source for the operation / stop control means 44.

Further, the DC output of the DC transformer 42 is supplied to DC drive electric devices such as electric valves V 1 to V 8 via drivers D 11 to D 18. Further, the DC output of the solar cell 41 is also supplied to the DC-driven electric devices 30 and 33 via the drivers D 21, D 22 ···.

Further, each driver D l '', D ll '', D 21 '' is connected to the operation Z stop control means 44 via a control line 46, and the operation Z stop control means 44 is connected to each driver D Each electric drive device can be operated and stopped via 1 · · ·, Ό 1 1 · ·, Ό 2 1 · ·. The output voltage of the solar cell 41 is detected by a voltage detector 45, and the detected output is input to the operation / stop control means 44.

As described above, the output of the solar cell 41 is input to the DC transformer 42 without passing through the battery, and the output of the DC transformer 42 is connected to the valve V 1 via the drivers D 11 to D 18. To V8, etc., and the output of the DC transformer 42 is input to the DC / AC converter 43, and the AC output is supplied to the raw water supply pump via the drivers D1 to D6. 1 1, Concentrated raw water discharge pump 16, Distilled water pump 25, Concentrated raw water circulation pump 17, Heat medium circulation pump 26, Blower fan 3-2, etc. Eliminates the need for batteries and charge controllers in the power supply equipment of the equipment.

In the above example, the heat medium circulating pump 26 is driven by the AC output from the DC / AC converter 43 via the driver D5, but is driven by the DC transformer 42. It may be a small DC pump driven by the DC output. It should be noted that other electric devices may be appropriately driven by DC or AC.

The electric valves V1 to V8 use electric valves that are mechanically closed when the amount of power generated by the solar cell 41 decreases and the voltage drops. 4 Although the power generation amount of 1 also decreases, the electric valves V1 to V8 are mechanically closed, so that the vacuum in the evaporation space and the condensing space of the evaporator 2 and the condensing space of the condenser 3-1 are broken. Never be.

In addition, the operation / stop control means 44 monitors the output of the voltage detector 45 and, when detecting that the amount of power generated by the solar cell 41 has dropped below a predetermined amount, switches the vacuum device 6 to distilled water (fresh water). ) The pump 25 and the concentrated raw water discharge pump 16 are stopped in priority. In addition, after the vacuum device 6 is stopped, if the power generation of the solar cell 41 further decreases, the distilled water pump 25 is stopped with priority given to the concentrated raw water discharge pump 16.

As described above, by stopping the vacuum device 6 prior to the distilled water pump 25 and the concentrated raw water discharge pump 16, the amount of power generated by the solar cell 41 decreases and only the electric motors are driven. When the power generation is lost, the vacuum device 6 with the least harm is preferentially stopped, and if the power generation of the solar cell 41 is still insufficient, the distilled water pump 25 with low risk of freshwater pollution is switched to freshwater. By shutting down the concentrated raw water discharge pump 16 which has a high risk of contamination, it is possible to prevent freshwater contamination.

As means for detecting the amount of power generated by the solar cell 41, in addition to a voltage detector 45 for detecting the output voltage of the solar cell 41, a pyranometer 48 or a small solar cell 47 is provided and its output is provided. May be output to the operation Z stop control means 44. The operation / stop control means 44 monitors the output of the pyranometer 48 or the small solar cell 47, and can know that the power generation of the solar cell 41 has decreased.

When the amount of power generated by the solar cell 41 decreases, the operation Z stop control means 44 stops each electric device in accordance with the priority and other predetermined orders according to the amount of decrease. Means 44 itself is configured to stop its function after all main electric devices have stopped. As a result, all the electric equipment stops and the operation stops when the operation Z stop control is no longer necessary, and the safe operation Z stop control of the desalination device becomes possible. Operation Z stop control means 4 4 is connected to heat medium temperature detector 3 1 and raw water flow rate detector 3 2, and heat medium at the outlet of solar heat collector 1 detected by heat medium temperature detector 3 1. The temperature and raw water flow rate detected by the raw water flow rate detector 32 are input.

The operation Z stop control means 4 4 monitors the temperature of the heat medium at the outlet of the solar heat collector 1 from the output of the heat medium temperature detector 31 and determines that the heat medium temperature becomes a predetermined temperature or lower than a predetermined temperature. The opening degree of the raw water flow control motor-operated valve V8 is controlled via the driver D18 to control the inflow of raw water W. As described above, by controlling the inflow of the raw water W so that the temperature of the heat medium at the outlet of the solar heat collector 1 is equal to or lower than the predetermined temperature, the heat medium of the solar heat collector 1 is controlled. It is possible to prevent the temperature and the temperature of the raw water W from increasing to a high temperature, thereby reducing the heat collection efficiency of the solar heat collector 1. Also, it is possible to prevent the inflow of the raw water w from the amount of insolation being too large, so that the temperature of the raw water w and the temperature of the heating medium become low, and the desalination ability of the device is reduced.

The operation / stop control means 4 4 monitors the inflow of the raw water W from the output of the raw water flow detector 32, and when the heat medium temperature of the solar heat collector 1 is higher than a predetermined temperature, the raw water flow detector 3 The opening of the raw water flow control motor-operated valve V8 is controlled via the driver D18 so that the inflow amount of the raw water W detected in step 2 always keeps a predetermined minimum flow rate. As described above, when the heat medium temperature is equal to or higher than the predetermined temperature, overconcentration of the raw water W can be prevented by always securing the inflow of the raw water W to a predetermined minimum flow rate.

If the flow rate of the raw water W detected by the raw water flow detector 32 is equal to or less than the predetermined value, even though the opening of the raw water flow control motor-operated valve V8 is set to the predetermined opening, the raw water W is cut off. Judge and stop the operation of the desalination plant. Specifically, the operation Z stop control means 44 sends a stop signal to the control line 46 to close the raw water flow control electric valve V8.

Before the desalination unit is operated, the operation control means 4 4 monitors the output of the concentrated raw water storage amount detector 34 and determines the storage amount of the concentrated raw water W in the lower tank 3-1 a of the condenser 3-1. If the amount is less than the amount, the raw water is supplied by the raw water supply pump 11 and the raw water flow control electric valve V8 in advance.

W is supplied to the degassing chamber 2-1 of the evaporator 2 and each evaporator, and the concentrated raw water in the concentrated water tank 5 of the evaporator 2 is supplied by the concentrated raw water discharge pump 16 and the concentrated raw water flow control valve V 6. W is supplied to the lower tank 3_1a of the condenser 3-1. As a result, when the desalination unit starts operating, the cooling water of the condenser runs short and the condensation capacity of the condenser decreases. Driving in a lowered position will no longer occur.

In addition, the operation control means 4 4 supplies the raw water supply pump 11 and the raw water supply pump 11 when the concentrated raw water W in the lower tank 3-1 a of the condenser 3-1 returns to a predetermined amount from the output of the concentrated raw water storage amount detector 34. The supply of the raw water W to the evaporator 2 is stopped by the raw water flow control electric valve V8, and the concentrated raw water W is condensed by the concentrated raw water discharge pump 16 and the concentrated raw water flow control valve V6. The lower tank of the condenser 3-1 3-1 Stop supplying to a.

As described above, when the concentrated raw water in the lower tank 3-1a of the condenser 3-1 recovers to a predetermined amount, the supply of the raw water to the evaporator 2 is stopped, and the concentrated raw water W is condensed in the condenser 3-1. Since the supply to the lower tank 3-1 a is stopped, the raw water is not supplied to the desalination unit more than necessary, and the temperature rise of the raw water heating by the heat medium from the solar heat collector 1 becomes slow. It is possible to prevent a decrease in the rate of generation of water vapor, that is, a rate of desalination due to a decrease in the temperature of raw water.

Applicability of the invention

The present invention is as described above. A desalination apparatus can be appropriately performed using a power source unique to the apparatus, and can efficiently produce fresh water even in a place where there is no other power supply facility such as a desert. Can be.

Claims

The scope of the claims

1. A desalination plant,

Solar collectors,

An evaporator that generates steam from the raw water by heating the raw water with heat from the solar collector;

A condenser for receiving water vapor generated from raw water heated in the evaporator from the evaporator and condensing it into distilled water;

A vacuum device for reducing the evaporation space in the evaporator and the condensation space in the condenser to below atmospheric pressure;

A power supply circuit including a power supply such as a solar cell that supplies power for driving an electric device such as the vacuum device in the desalination apparatus;

A control device that prioritizes and stops the power supply to the electric device when the power generation amount of the power supply falls below a predetermined amount;

A desalination apparatus comprising:

2. The desalination apparatus according to claim 1,

The electric equipment includes a freshwater discharge pump for discharging distilled water produced by a condenser, and a concentrated raw water discharge pump for discharging the concentrated raw water,

The control device has a power generation amount detection device that detects a power generation amount of a power supply,

The control device, when the power generation amount detection device detects that the power generation amount of the power supply has decreased to a predetermined amount or less, stops the vacuum device before the fresh water discharge pump and the concentrated raw water discharge pump. A desalination apparatus characterized in that:

3. The desalination apparatus according to claim 2,

When the power generation amount detection device detects that the power generation amount further decreases after the power supply to the vacuum device is stopped, the power supply to the freshwater discharge pump is performed earlier than the concentrated raw water discharge pump. A desalination apparatus characterized by being stopped.

4. The desalination apparatus according to claim 3,

The control device is configured to stop the function after the power generation amount detection device detects that the power generation amount of the power supply has decreased to a predetermined amount or less and all the electric devices have stopped functioning. And the power generation amount of the power source recovers to a predetermined amount or more. The desalination apparatus is characterized in that, when it is detected, the function of the electric device is restored before the function of the electric device is restored.

5. The desalination apparatus according to any one of claims 1 to 4,

The power supply is a solar cell, The power generation amount detection device is a pyranometer for detecting the amount of solar radiation, or a desalination characterized by a small solar cell provided separately from the solar cell

6. The desalination apparatus according to any one of claims 1 to 5,

The desalination apparatus has, as the electric device, an electric opening / closing valve used in a raw water supply / discharge line / a fresh water discharge line or the like. Desalination characterized by being a mechanically closed electric valve

7. The desalination apparatus according to claim 6,

The desalination apparatus, wherein the evaporator includes a plurality of evaporators, and the evaporators are connected in a multiple effect relationship.

8. Solar collectors,

An evaporator,

A raw water supply device for supplying raw water to the evaporator,

A heat medium circulating circuit for circulating a heat medium between the evaporator and the solar heat collector, and using the heat medium heated by the solar heat collector as a heat source of raw water in the evaporator;

A condenser for receiving water vapor generated in the evaporator from the evaporator and condensing it into distilled water;

A heating medium temperature detector that detects a temperature of a heating medium that enters the evaporator from the solar heat collector, a raw water flow controller that controls a flow rate of raw water supplied from the raw water supply device, and a raw water flow controller. A desalination system comprising a control device for controlling the flow rate of raw water supplied to the evaporator so as to control the temperature of the heat medium supplied to the evaporator to a predetermined temperature or lower than a predetermined temperature. apparatus.

9. The desalination apparatus according to claim 8,

When the temperature of the heating medium supplied to the evaporator is equal to or higher than a predetermined temperature, the control device always ensures that a flow rate of the raw water supplied to the evaporator has a predetermined minimum flow rate. A desalination apparatus characterized by controlling a raw water flow controller.

10. The desalination apparatus according to claim 9,

The raw water flow controller has an electric valve,

The control device includes a raw water flow rate detector, and the detector determines that a raw water flow rate supplied to the evaporator is equal to or less than a predetermined value even though the electric valve is at a predetermined opening. A desalination plant characterized by determining that raw water is cut off when detected, and stopping the operation of the desalination plant.

1 1. Solar collector and

A raw water supply device for supplying raw water to the evaporator,

A concentrated raw water storage tank that stores raw water that is supplied from a raw water supply device, passes through the evaporator, is heated, generates steam, and stores concentrated raw water;

A concentrated raw water storage amount detector for detecting the concentrated raw water storage amount in the concentrated raw water storage tank, wherein the condenser uses the concentrated raw water in the concentrated raw water storage tank as cooling water for the condenser. It is made to

Before the operation of the desalination device, when the concentrated raw water storage amount detected by the concentrated raw water storage amount detector is equal to or less than a predetermined amount, raw water is supplied to the evaporator in advance by the raw water supply device, and the evaporating device is A desalination apparatus, comprising: a control device for supplying the raw water passed through to the concentrated raw water storage tank so that the storage amount becomes the predetermined amount.

1 2. The desalination apparatus according to claim 11,

The concentrated raw water storage tank is provided in the condenser, and a concentrated raw water discharge pump that supplies concentrated raw water from the evaporator to the concentrated raw water storage tank is provided, and the concentrated raw water storage detected by the concentrated raw water storage amount detector is provided. The desalination apparatus, wherein when the amount is equal to or less than a predetermined amount, the control device operates the concentrated raw water discharge pump.

1 3. The solar heat collector and the raw water are heated by the heat from the solar heat collector. An evaporator for generating water vapor from the raw water, a condenser for receiving the water vapor generated from the raw water heated in the evaporator from the evaporator and condensing it into distilled water; an evaporating space in the evaporator; A vacuum device for reducing the condensing space in the condenser to an atmospheric pressure or less, and a power supply circuit including a power supply such as a solar cell for supplying electric power for driving an electric device such as the vacuum device in the desalination device. A method for controlling a desalination apparatus, comprising:

A method of controlling a desalination apparatus, wherein when the amount of power generated by a power supply decreases to a predetermined amount or less, the electric devices are stopped in a priority order.

14. The method for controlling a desalination apparatus according to claim 13,

The desalination apparatus has, as the electric equipment, a freshwater discharge pump for discharging distilled water produced by a condenser, and a concentrated raw water discharge pump for discharging the concentrated raw water. ,

A step of detecting that the power generation amount of the power supply has dropped below a predetermined amount,

Stopping the power supply to the vacuum device before the freshwater discharge pump and the concentrated raw water drainage pump;

A method for controlling a desalination apparatus, comprising:

15. In the method for controlling a desalination apparatus according to claim 14,

After the power supply to the vacuum device is stopped, when it is detected that the power generation amount further decreases, the power supply to the freshwater discharge pump is stopped before the concentrated raw water discharge pump. A method for controlling a desalination apparatus.

16. The method for controlling a desalination plant according to claim 15,

When it is detected that the power generation amount of the power supply has decreased to a predetermined amount or less, the function of the control device is stopped after all the electric devices have stopped functioning, and the power generation amount of the power supply is A method for controlling a desalination device, characterized in that when it is detected that the electric device has recovered to a predetermined amount or more, the function of the control device is restored before the function of the electric device is restored.