JPH091127A - Device for forming fresh water from sea water - Google Patents

Abstract

PURPOSE: To make it possible to economically form fresh water from sea water by maintaining the temp. in an evaporating column at about a temp. below the freezing point, evaporating the sea water, guiding the steam to the lower part of an ice making column, bringing the steam into contact with the surface of the fresh water to allow ice to grow, thawing the ice and taking out the water as the fresh water. CONSTITUTION: While the sea water is injected into a sea water tank 3 by using a water feed pump 4, the fresh water 15 is injected from a water take-out port 7 into the ice making column 1. A vacuum pump 5 is then started to evacuate the inside of the ice making column 1 and the evaporating column 2 and to lower the temp. in the columns. The sea water is passed to a water flow pipe 8 having a check valve 16 and is risen up to the upper part in the evaporating column 2. The fresh water 15 begins to freeze when the temp. below the freezing point is attained in the ice making column 1 and therefore, the hot water or steam is passed into a heater 18 or heat exchanger 13 and the vapor held near the temp. below the freezing point is guided to the lower part of the ice making column 1 and is brought into contact with the surface of the fresh water 25 to allow the ice to grow. The temp. is risen up to the temp. above the freezing point to thaw the ice when the prescribed amt. of the ice is formed. The water is then taken as the fresh water out of the water take-out port 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for separately producing salt or concentrated salt water and water or ice as fresh water from an aqueous solution containing salt as a main component.

[0002]

2. Description of the Related Art Conventionally, a method of collecting salt from seawater has been known as a salt production method. In the old days, the sun salt production method and the salt field salt production method utilizing natural evaporation by the sun have been used for the purpose of separating and producing salt. There is.

The above-mentioned conventional method for directly collecting salt from seawater without utilizing natural evaporation includes a pressure type or a vacuum type as a method for directly heating and concentrating with steam. I am trying.

Recently, an ion-exchange electric field tank system is often used as a method for separating water and salts, and a large number of ion-exchange membranes are used to convert cations and anions in seawater into electricity. This is a method using a method of physically separating.

[0005]

SUMMARY OF THE INVENTION In the conventional sun salt making method and salt field salt making method, or in the method of directly heating and concentrating with steam, the purpose is to separate and produce salt, and fresh water is not separated. .

The ion exchange electric field tank system which has been attempted recently is intended to separate water and salt, but it requires a large amount of electric power, the process is large and complicated, and the ion exchange resin is expensive and economical. Was not good.

It is an object of the present invention to solve the above-mentioned conventional drawbacks and to provide an economical apparatus for producing fresh water from seawater, which has a simple structure and a simple structure in which water and salt are separated from seawater at the same time. And

[0008]

In the apparatus for producing fresh water from seawater according to the present invention, an ice making tower forming a heat-insulating hermetic container and an evaporating tower forming a heat-sealing hermetic container adjacent to the ice-making tower are respectively placed upright. Installed and connected steam pipes and connecting pipes from the upper part of the evaporation tower to the lower part and the upper part of the ice making tower, respectively, and extend the lower part of the evaporation tower to form a salt reservoir, and the lower part to take out salt or concentrated salt water. , A seawater tank having an overflow pipe for replenishing seawater with a water supply pump or the like adjacent to the evaporation tower, is connected to the lower part of the evaporation tower using a water pipe, and a check valve is attached to the water passage, and the evaporation tower is attached. Built-in heater or heat exchanger with hot water inlet and hot water outlet,
If necessary, a splash entrainment prevention net is built in above the evaporation tower,
It is characterized in that an outlet for fresh water or ice is provided in the lower part of the ice making tower, and a vacuum pump connected to an intake pipe is installed in the upper part of the ice making tower.

[0009]

According to the present invention, seawater as a source water is poured into the seawater tank in the above-mentioned seawater-to-freshwater generator by using the water supply pump, and the surplus water is naturally discharged from the overflow pipe.
Then, using a water outlet inside the ice making tower, fresh water was back-injected to the height of the water outlet as seed water for ice making, the water outlet and the salt outlet were closed, the vacuum pump was started, and the heat-insulated hermetic container was closed. The inside of the ice-making tower and the evaporation tower to be formed is evacuated and the atmospheric pressure decreases, and the temperature also decreases due to the evaporative cooling action of fresh water and seawater, respectively, and the seawater in the seawater tank has a check valve to prevent backflow. The inside of the evaporation tower rises through and is stopped by a check valve before passing the steam pipe, and when the temperature becomes below freezing point, fresh water as seed water for ice making begins to ice, and at this point hot water or steam is passed through the heater or heat exchanger. When the temperature inside the steam tower is kept below the freezing point, seawater does not freeze due to the freezing point drop of an aqueous solution containing a non-volatile solute like seawater, but due to the boiling point drop due to the low pressure of water When it is used as water, when it is used as water, it is emitted to the lower part of the ice making tower through the steam pipe and the connecting pipe and comes into contact with the fresh water surface to grow ice, which has a pumping function. When the temperature is raised above the freezing point using the heater or heat exchanger, and when the ice inside the ice making tower is completely melted, the vacuum pump is stopped and water is taken out from the water outlet and used as ice. Can be taken out immediately by stopping the vacuum pump, and the seawater concentrated in the lower part of the steam tower produces precipitated salt, which is collected in the salt pool, and can be taken out from the outlet as salt or concentrated salt water.
An apparatus for producing fresh water from seawater can be provided.

[0010]

An embodiment of the present invention will be described below. FIG. 1 shows a schematic view of a device for producing fresh water from seawater according to the present invention. An ice making tower (1) that forms a heat-insulating sealed container in the longitudinal direction is installed upright, and an evaporation tower (2) that forms a heat-insulating sealed container of approximately the same height is installed upright next to it, and the upper part of the evaporation tower is installed. To the lower part and the upper part of the ice-making tower, respectively, connecting a steam pipe (9) and a connecting pipe (10), and extending the lower part of the evaporation tower to form a salt reservoir, a valve and the like, and a salt outlet (6),
A seawater tank (3) having an overflow pipe (17) for replenishing seawater by a water supply pump (4) adjacent to the evaporation tower is connected to the lower part of the evaporation tower by using a water passage pipe (8) and connected to the water passage pipe. A check valve (16) was attached, and a heater (1
8) Or a built-in heat exchanger (13) having a hot water inlet (11) and a hot water outlet (12), and if necessary, a splash entrainment prevention net formed of glass fiber bundles or the like to prevent boiling splash liquid ( 14) is built in the upper part of the evaporation tower, a water outlet (7) having a valve and the like is provided in the lower part of the ice making tower, and a vacuum pump (5) connected to an intake pipe is installed in the upper part of the ice making tower. It is characterized by being

[0011]

As described above, seawater as a source water is poured into the seawater tank (3) by using the freshwater generator from the seawater according to the present invention and the surplus water is overflow pipe. (17) to allow natural outflow, and then, using the water outlet (7) inside the ice making tower, back-inject fresh water (15) as seed water for ice making up to the height of the water outlet, and then the water outlet and salt Close the outlet (6) and vacuum pump (5)
The inside of the ice making tower (1) and the evaporation tower (2) is exhausted and the atmospheric pressure drops, and the temperature also drops due to the evaporative cooling action, and the seawater in the seawater tank has a check valve (16). The vapor pipe (9) rises inside the evaporation tower through the water passage pipe (8).
When the temperature falls below the freezing point, the fresh water as the seed water for ice making begins to ice, and at this point, the hot water inlet (1) is connected to the heater (18) or the heat exchanger (13).
1) and hot water outlet (12) are used to pass hot water or steam to keep the internal temperature of the steam tower below the freezing point, the steam is guided to the lower part of the ice making tower through the steam pipe and the connecting pipe (10). Ice that grows in contact with fresh water and has a pumping function, has a pumping capacity lower than when pumping only with a vacuum pump, and is highly effective both structurally and economically. A fresh water generator can be provided.

When a predetermined amount of ice is generated inside the ice making tower (1) using the apparatus for producing fresh water from seawater according to the present invention,
When it is used as water, the temperature inside the steam tower is set to the heater (1
8) or using a heat exchanger (13) to raise the temperature above the freezing point, and when all the ice inside the ice making tower has melted, stop the vacuum pump and take in water from the water outlet (7) and use it as fresh water. It also has the effect that the vacuum pump can be stopped immediately and ice can be used.

An apparatus for producing fresh water from seawater according to the present invention is
Not only water as fresh water but also ice, and at the same time can be separated and produced as salt or concentrated salt water, it is a single closed system device with a simple structure, so the process is simple and there are few failures, and the water supply pump (4) Also, it is possible to provide an economical seawater-to-freshwater generator that requires only the power of the vacuum pump (5) having a low exhaust capacity.

[Brief description of the drawings]

FIG. 1 is a schematic view of an apparatus for producing fresh water from seawater, showing an embodiment of the present invention.

[Explanation of symbols]

 1 Ice Tower 2 Steam Tower 3 Sea Water Tank 4 Water Pump 5 Vacuum Pump 6 Salt Outlet 7 Water Outlet 8 Water Pipe 9 Steam Pipe 10 Connecting Pipe 11 Hot Water Inlet 12 Hot Water Outlet 13 Heat Exchanger 14 Splash Prevention Network 15 Fresh Water 16 Check valve 17 Overflow pipe 18 Heater

Claims (1)

[Claims] 1. An ice-making tower and an evaporation tower forming a heat-insulated sealed container are installed adjacent to each other, and a vapor pipe and a connecting pipe are connected from the upper part of the evaporation tower to the lower part and the upper part of the ice-making tower, respectively, The lower part is extended to form a salt reservoir, and the lower part is used as an outlet for salt or concentrated salt water, and a seawater tank adjacent to the evaporation tower for supplying seawater by a water supply pump or the like is connected to the lower part of the evaporation tower using a water pipe. A valve is attached to the water passage, a heater or a heat exchanger having a hot water inlet and a hot water outlet is built in the inside of the evaporation tower, and if necessary, a splash entrainment prevention net is built in the upper part of the evaporation tower, and the ice making tower A water or ice outlet is provided at the bottom, and a vacuum pump connected to an intake pipe is installed at the top of the ice making tower. It is possible to separate fresh water or ice and salt or concentrated brine. A device for producing fresh water from seawater.