Abstract
Apparatus and methods are disclosed for separating salts, minerals, organic matter and other impurities from seawater, brackish water, wastewater or other water resources by freezing contained water in a downward vertical direction. Generally, feed water is pumped into a tank and a refrigerant contacts the upper surface of the feed water to form a layer of ice. During this process, salt and other impurities are rejected from the ice layer into the feed water below. By continuing this process, the feed water will freeze in a downward direction as the ice layer thickens. Salt and other impurities will continue to be rejected into the feed water and may be drained from the tank through a drain pipe after a block of ice is formed. Additional feed water may then be pumped into the tank to raise the block of ice for removal or ejection from the tank. The block of ice may then be melted to provide product water. Multiple tanks may be arranged in multiple levels using shared pipes and conveyor platforms to increase efficiency, scale and production.
Claims
1. An apparatus for separating salt, minerals, organic matter or other impurities from seawater, brackish water, wastewater or other water resource, comprising: at least one tank having at least one opening for supplying a refrigerant to an upper portion of said tank; at least one water intake pipe connected to said tank for supplying feed water into said tank; and at least one drain pipe connected to said tank for draining a portion of said feed water from said tank.
2. The apparatus of claim 1, wherein at least one block of ice may be raised through said opening of said tank by supplying additional feed water into said tank.
3. An apparatus for separating salt, minerals, organic matter or other impurities from seawater, brackish water, wastewater or other water resource, comprising: at least one enclosed tank having at least one panel which may be opened and closed; at least one refrigerant intake pipe connected to said enclosed tank for supplying refrigerant to an upper portion of said enclosed tank; at least one water intake pipe connected to said enclosed tank for supplying feed water into said tank; and at least one drain pipe connected to said tank for draining a portion of said feed water from said enclosed tank.
4. The apparatus of claim 3, wherein said refrigerant intake pipe may be used as a refrigerant exhaust pipe for removing said refrigerant from said enclosed tank.
5. The apparatus of claim 4, wherein at least one block of ice may be raised by supplying additional feed water into said enclosed tank.
6. The apparatus of claim 5, wherein said refrigerant may be displaced from said enclosed tank by said raising of said block of ice with said additional feed water.
7. The apparatus of claim 6, wherein said refrigerant may be used to eject said block of ice from said enclosed tank with positive pressure.
8. The apparatus of claim 3, wherein said enclosed tank has at least one insulation chamber between at least one internal wall and at least one external wall of said enclosed tank.
9. The apparatus of claim 8, further comprising an insulation intake pipe connected to said insulation chamber for supplying a fluid to control the temperature of said internal wall.
10. A method for separating salt, minerals, organic matter or other impurities from seawater, brackish water, wastewater or other water resource, comprising: supplying feed water into at least one tank; freezing said feed water in a downward vertical direction by supplying a refrigerant to the upper surface of said feed water; and draining brine from said tank after at least one block of ice is formed by said freezing of said feed water.
11. A method according to claim 10, further comprising raising said block of ice by supplying additional feed water into said tank.
12. A method according to claim 10, further comprising enclosing said tank.
13. A method according to claim 12, wherein said raising of said block of ice displaces said refrigerant from said enclosed tank.
14. A method according to claim 13, further comprising using positive pressure to eject said block of ice from said enclosed tank.
15. A method according to claim 14, wherein said positive pressure is produced by supplying said displaced refrigerant into said enclosed tank.
16. A method according to claim 12, wherein said enclosed tank further comprises at least one insulation chamber between at least one internal wall and at least one external wall of said enclosed tank and a fluid is supplied into said insulation chamber to control the temperature of said internal wall.
17. A method according to claim 16, wherein said feed water is insulated from said refrigerant along said internal wall to facilitate freezing of said feed water in a downward vertical direction.
18. A method according to claim 17, wherein said internal wall is heated by a fluid in said insulation chamber to melt at least one surface of said block of ice along said internal wall.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a schematic view of an apparatus for freezing water in a downward vertical direction.
[0018] FIG. 2 is a schematic view of the apparatus shown in FIG. 1, further showing a refrigerant supplied to the upper surface of feed water contained in the apparatus.
[0019] FIG. 3 is a schematic view of the apparatus shown in FIG. 1, further showing a block of ice formed by freezing water in a downward vertical direction.
[0020] FIG. 4 is a schematic view of the apparatus shown in FIG. 1, further showing a block of ice raised by additional feed water for removal by a mechanical device.
[0021] FIG. 5 is a schematic view of another embodiment of an apparatus for freezing water in a downward vertical direction.
[0022] FIG. 6 is a schematic view of the apparatus shown in FIG. 5, further showing a block of ice raised by additional feed water for ejection by a refrigerant with positive pressure.
[0023] FIG. 7 is a schematic view of the apparatus shown in FIG. 5, further showing an insulation chamber for insulating the feed water from the refrigerant and melting surfaces of the block of ice to facilitate vertical movement.
[0024] FIG. 8 is a simplified plan view of multiple tanks in accordance with the present invention that are adjacent to a conveyor platform for conveying blocks of ice.
[0025] FIG. 9 is a schematic view of multiple tanks in accordance with the present invention that are arranged in multiple levels for increased efficiency, scale and production.
DETAILED DESCRIPTION
[0026] Referring to FIG. 1, feed water 10 from a water resource such as seawater, brackish water or wastewater is pumped into a tank 20 through a water intake pipe 30 and discharged through a drain pipe 40. As shown in FIG. 2, a refrigerant 50 such as chilled air, nitrogen or oxygen is supplied to the upper surface of the water 10 contained in the tank 20 at an appropriate temperature to form a layer of ice 60. During this freezing process, water molecules crystallize to form a lattice structure which allows the ice layer 60 to float on top of the water 10 while rejecting salt, organic compounds, minerals or other impurities into the water 10 beneath the layer of ice 60.
[0027] Referring to FIG. 3, the temperature of the refrigerant 50 is indirectly transferred through the layer of ice 60 to continuously freeze the water 10 in a downward vertical direction until a block of ice 60a is formed. Impurities are then discharged with the remaining water 10 through the drain pipe 40. As shown in FIG. 4, feed water 10a is then pumped into the tank 20 to raise the block of ice 60a above at least one wall of the tank 20 and a mechanical device such as a push rod 70 or moveable arm is used to remove the block of ice 60a from the tank 20. The block of ice 60a is then melted to provide product water.
[0028] In an alternative embodiment, shown in FIG. 5, feed water 10 is pumped into an enclosed tank 20a through a water intake pipe 30 and discharged through a drain pipe 40. Refrigerant 50 is pumped into the enclosed tank 20a through a refrigerant intake and exhaust pipe 32, which may consist of separate pipes. As in the previous embodiment, the refrigerant 50 freezes the contained water 10 to form a block of ice 60a. After rejected impurities are discharged with the remaining water 10 through the drain pipe 40, additional feed water 10a is pumped into the enclosed tank 20a to raise the block of ice 60a, as shown in FIG. 6. During this process, the block of ice 60a displaces the refrigerant 50 out of the enclosed tank 20a and the refrigerant is removed through the refrigerant intake and exhaust pipe 32. A panel 22 of the enclosed tank 20a is then opened, for example by swinging or sliding the panel, to enable the block of ice 60a to be removed from the enclosed tank 20a. The displaced refrigerant 50 is then pumped or otherwise supplied back into the enclosed tank 20a through the refrigerant intake and exhaust pipe 32 to eject the block of ice 60a out the opening of panel 22 with positive pressure. After the block of ice 60a is completely outside the tank 20a, the panel 22 is closed. In this manner, the refrigerant 50 may be recycled or recirculated in order to reduce or minimize the amount of energy required to form multiple blocks of ice 60a. The feed water 10a may also be partially drained through the drain pipe 40 to draw additional refrigerant 50 into the tank 20a through the refrigerant intake and exhaust pipe 32 with negative pressure after the ice block 60a has been ejected.
[0029] FIG. 7 shows another embodiment of the present invention with a double-walled tank 20b having an insulation chamber 24 between internal 26 and external 28 walls of the tank 20b. A fluid 80, such as oil or air, is pumped into the insulation chamber 24 through an insulation intake pipe 34 in order to control or modify the temperature of the internal walls 26. When the temperature of the internal walls 26 is higher than the temperature of the water 10 contained inside the tank 20b, the water 10 will be insulated from the refrigerant 50 along the internal walls 26. This insulation will allow the refrigerant 50 to freeze the upper surface 60 of the water 10 in a downward vertical direction to form a block of ice 60a. After the block of ice 60a is formed, the temperature of the internal walls 26 may be increased to facilitate vertical movement of the block of ice 60a by pumping a higher temperature fluid 80a (not shown) through the insulation intake pipe 34 and purging or removing the lower temperature fluid 80 through an insulation exhaust pipe 36. The increased temperature of the internal walls 26 will facilitate vertical movement of the block of ice 60a by melting the surfaces of the block of ice 60a that contact the internal walls 26. As in the previously described embodiments, the block of ice 60a is raised by pumping additional feed water 10a into the tank 20b and then removed by opening the panel 22 and pumping the refrigerant 50 into the tank 20b to eject the block of ice 60a outside the tank 20b with positive pressure.
[0030] FIG. 8 shows a simplified plan view of multiple tanks 20b adjacent to a conveyor platform 90. The tanks 20b are positioned with their panels 22 alongside the conveyor platform 90 so that blocks of ice 60a (represented by arrows) are ejected out the opened panels 22 onto the conveyor platform 90. The blocks of ice 60a are then conveyed along the conveyor platform 90 to one or more locations where they will melt into product water. To facilitate conveyance of the blocks of ice 60a, the conveyor platform 90 may contain a liquid 100 such as freshwater to allow the blocks of ice 60a to float as they are conveyed with mechanical devices such as motorized belts or rollers, or by active flow of the liquid 100. The conveyor platform 90 may also be inclined to allow the blocks of ice 60a to float or slide down the conveyor platform 90 with gravitational force.
[0031] Multiple tanks 20b may also be arranged in multiple levels, as shown in the sectional view of FIG. 9. Conveyor platforms 90 may be provided between tanks 20b at each level and positioned beneath the panels 22 to capture the blocks of ice as they are ejected from the tanks 20b. Multiple tanks 20b may also share pipes, such as insulation exhaust pipes 36 and water drain pipes 40. Although not shown, other pipes may be shared by the tanks 20b as well.
[0032] While several embodiments of the present invention have been described above, it should be understood that other variations, modifications, equivalents and embodiments may be made or used by those skilled in the art without departing from the scope and spirit of the present invention.
