A desalination system

Abstract

A desalination system includes a water pump for pumping saltwater from a water source. Heat exchangers are provided for heating and cooling fluids traveling through the desalination system. A swirl pump is provided for mixing heated saltwater and heated solvent together. A vortex separator is used to separate a brine / salt crystal mixture and a water / solvent solution from a heated solution. An underflow pump draws brine mixture and salt crystals from the vortex separator and a sonic chamber is used to complete salt crystallization from the brine mixture. A salt dump is provided for separation and disposal of salt. A fluid-fluid separator is used to separate the water / solvent mixture into a separated solvent and a desalinated water.

Description

TITLE

[0001] A Desalination SystemFIELD OF THE DISCLOSURE

[0002] The present application relates generally to a desalination system for desalinating saltwater.BACKGROUND

[0003] This section provides background information to facilitate a better understanding of the various aspects of the invention. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art.

[0004] Seawater desalination plays a critical role in addressing the water shortage challenges affecting approximately 40% of the World's population. There are approximately 16000 operational desalination plants, located in 177 countries, which generate an estimated 95 million m3 / day of fresh water. Reverse osmosis is the dominant technology being used in seawater desalination and is economically competitive with other technologies such as evaporation processes. There are a number of disadvantages to reverse osmosis, including degradation of coastal marine ecosystems by pumping heated brine polluted with chlorine and copper back into the ocean, high energy consumption resulting in high volumes of greenhouse gases released into the atmosphere, the removal of essential nutrients and ions from the water which can result in health problems and corrosion in water distribution pipes, and a frequent need to replace degrading membranes used in the process.

[0005] A recent advancement for the desalination of salt water is the directional solvent extraction (DSE) method. This method utilizes a solvent mixed with saline water to separate the water from salt and other impurities.BRIEF SUMMARY

[0006] There is provided a desalination system. A water pump is used to pump saltwater from a water source. A first heat exchanger has a saltwater inlet in fluid communication with the water pump, a saltwater outlet, a first solution inlet, and a first solution outlet. A second heat exchanger has a solvent inlet, a solvent outlet, a second solution inlet, and a second solution outlet. The solvent inlet is in fluid communication with a solvent source, the second solution outlet is in fluid communication with the first solution inlet of the first heat exchanger. A swirl pump is in fluid communication with the saltwater outlet of the first heat exchanger and the solvent outlet of the second heat exchanger such that a heated saltwater from the first heat exchanger and a heated solvent from the second heat exchanger are mixed together by the swirl pump to create a saltwater / solvent mixture. A third heat exchanger has a saltwater / solvent mixture inlet, a solution mixture outlet, a heated fluid inlet, and a cooled fluid outlet. The saltwater / solvent mixture inlet is in fluid communication with the swirl pump such that the saltwater / solvent mixture is heated by the third heat exchanger such that the solvent absorbs water to become a solvent / water solution, salt is crystallized, and a brine mixture is formed. A vortex separator has at least one solution vortex inlet and a waste outlet. The at least one solution vortex inlet is in fluid communication with the solution mixture outlet of the third heat exchanger. The at least one solution vortex inlets are positioned adjacent a top of the vortex separator as a tangential connection. The waste outlet is positioned at a bottom of the vortex separator. A cyclone chamber is positioned below the at least one solution vortex inlet. The cyclone chamber creates an outer vortex and an inner vortex to separate a brine mixture and a water / solvent solution from the solution. The brine mixture is moved to the outer vortex and the water / solvent solution moves to the inner vortex which rises up a center of the cyclone chamber to a vortex finder positioned at the top of the vortex separator. The vortex finder has a solution vortex outlet in fluid communication with the second solution inlet of the second heat exchanger. A portion of the water / solvent solution from the inner vortex passes through the solution vortex outlet and a portion of the water / solvent solution from the inner vortex is diverted back into the cyclone chamber to create an return vortex. The return vortex mixes with the inner vortex and rises upwards. An underflow pump is in fluid communication with the waste outlet of the vortex separator and a sonic chamber. The underflow pump draws brine mixture and salt crystals from the vortex separator into the sonic chamber. The sonic chamber has at least one ultrasonic transducer mounted on a perimeter of the sonic chamber. The at least one ultrasonic transducers producing ultrasonic sound waves which are used to complete salt crystallization from the brine mixture. The sonic chamber has asonic chamber waste outlet and a sonic chamber solution outlet, the sonic chamber waste outlet allowing for the removal of salt crystals and the brine mixture, the sonic chamber solution outlet being in fluid communication with a center of the underflow pump such that the sonic chamber solution outlet is in fluid communication with the cyclone chamber. A salt dump is provided for removal of salt through the sonic chamber waste outlet. A fluid-fluid separator has a separator solution inlet, a solvent outlet, and a water outlet. The separator solution inlet is in fluid communication with the first solution outlet of the first heat exchanger. The water / solvent solution is separated into a separated solvent and a desalinated water.

[0007] In one embodiment, a salt dump is provided. The salt dump has a salt dump inlet, a salt outlet, a drain, and a fluid source inlet. The salt dump inlet being in fluid communication with the sonic chamber outlet.

[0008] In one embodiment, the salt dump has four chambers rotatable on an axis in a first direction. Each of the four chambers is in one of four positions. In a first position, a first of the four chambers is in fluid communication with the sonic chamber outlet for collection of salt crystals, brine mixture and waste. In a second position, a second of the four chambers is in fluid communication with the drain. In a third position, a third of the four chambers is in communication with the salt outlet. In a fourth position, a fourth of the four chambers is in fluid communication with the fluid source inlet. A level switch is positioned in the chamber in the first position such that triggering of the level switch causes a 90 degree rotation of the four chambers in the first direction towards the drain.

[0009] In one embodiment, the second heat exchanger has a salt dump outlet in fluid communication with the salt dump such that fluid from the second heat exchanger flows through the salt dump outlet to the fluid source inlet to fill the fourth of the four chambers in the fourth position with fluid and vent gases within the salt dump during and after completion of a quarter turn rotation of the four chambers.

[0010] In one embodiment, there is a pair of solution mixture vortex inlets. The pair of solution mixture vortex inlets are positioned on opposed sides of an inlet chamber adjacent a top of the vortex separator.

[0011] In one embodiment, the first heat exchanger, the second heat exchanger, and the third heat exchanger are helical coil heat exchangers.

[0012] In one embodiment, the fluid-fluid separator is a parallel plate pack separator. The solvent outlet is on a first side chamber of a weir and the water outlet is on a second side chamber of the weir.

[0013] In one embodiment, the desalinated water has no more than 1 gram per liter of salt content.

[0014] In one embodiment, the underflow pump has a magnetic drive with a rotor and a stator. The rotor is connected to an impeller and rotation of the impeller causes an increase in the rotation speed of the brine mixture which causes the heavier components of the mixture to move to the perimeter of the underflow pump due to centrifugal force as the brine mixture travels through the sonic chamber. A displaced water / solvent solution travels up the center of the underflow pump towards the vortex separator. The displaced water / solvent solution is the solution that is displaced by the brine mixture travelling down the sonic chamber, this may include fluid from the fluid source inlet that travels through the salt dump.

[0015] In one embodiment, an elevated and vented chamber is positioned between and in fluid communication with the first solution outlet of the first heat exchanger and the separator solution inlet of the fluid-fluid separator.

[0016] In one embodiment, a heater is positioned upstream of the heated fluid inlet of the third heat exchanger to heat the fluid flowing through the third heat exchanger.

[0017] In one embodiment, the heated fluid inlet of the third heat exchanger and the cooled fluid outlet of the third heat exchanger are a closed loop such that a heating fluid circulates in the closed loop.BRIEF DESCRIPTION OF THE DRAWINGS

[0018] These and other features will become more apparent from the following description in which references are made to the following drawings, in which numerical references denote like parts. The drawings are for the purpose of illustration only and are not intended to in any way limit the scope of the invention to the particular embodiments shown.

[0019] FIG. 1 is a schematic view of a desalination system.

[0020] FIG. 2 is a side elevation view, in section, of the vortex separator and two heat exchangers of the desalination system.

[0021] FIG. 3 is a side elevation view, in section, of a salt dump usable in the desalination system.

[0022] FIG. 4 is a side elevation view, in section, of a parallel plate pack separator useable in the desalination system.

[0023] FIG. 5 is a side elevation view, in section, of a sonic chamber useable in the desalination system.

[0024] FIG. 6 is a top plan view, in section, of an underflow pump useable in the desalination system.

[0025] FIG. 7 is a side elevation view, in section, of the underflow pump shown in FIG. 6.

[0026] FIG. 8 is a top plan view of the sonic chamber shown in FIG. 5.

[0027] FIG. 9 is a side elevation view, in section, of a third heater exchanger useable in the desalination system.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] A desalination system, generally identified by reference numeral 10, will now be described with reference to FIG. 1 through FIG. 9.

[0029] Referring to FIG. 1, desalination system 10 is used to reduce the salt content of water. System 10 may work with saltwater having any amount of salt and reduce the salt content to such a degree that the water becomes drinkable. Saltwater from the ocean generally has a salt content of approximately 35 grams per liter with some variation. It will be understood by a person skilled in the art that drinkable water is generally considered to be water having 0.6 grams of salt per liter or less, however some variability in this amount is to be expected. System 10 preferably reduces salt content to less than 1 gram per liter.

[0030] A water pump 12 is used to pump saltwater from a water source 14, such as the ocean. Water pump 12 has flow controllers to regulate the flow rate of fluid in system 10. Other pumps will have the same or similar flow controllers to aid in the regulation of flow rate throughout system 10. Saltwater may be pretreated prior to entering system 10 or through use of specific chemical additive pumps. Pretreatment may include treatment with ozone, filtering solids, silt, scale, oil and grease, naturalorganic contamination and aquatic microorganisms, or reducing dissolved oxygen concentrations. Other pretreatments would be known to a person skilled in the art. A beach well seawater intake may filter many of contaminants as the seawater moves through the sand layers surrounding the intake and reduce the salinity of the saltwater and oxygen concentrations. Saltwater may also be drawn from other sources such as aquifers and other sources known to a person skilled in the art. Saltwater is pumped from water source 14 to a first heat exchanger 16. First heat exchanger 16 has a saltwater inlet 18, a saltwater outlet 20, a first solution inlet 22, and a first solution outlet 24. Saltwater entering through saltwater inlet 18 is heated as the saltwater flows through first heat exchanger 16 and exits through saltwater outlet 20. During start-up of system 10, saltwater may be released back to water source 14 by a three-way valve 26 to allow for the circulation of fluid through system 10 until a preferred temperature of the liquid within a vortex separator 54 has been reached. The preferred temperature may be as low as 40 degrees Celsius but should be lower than 100 degrees Celsius to prevent evaporation. The higher the preferred temperature, the more energy input is required into system 10. In the embodiment shown, first heat exchanger 16 is a helical coil heat exchanger, however it will be understood by a person skilled in the art that other types of heat exchangers may be used. A cooling tower may be installed at an inlet of water pump 12 to lower the temperature of seawater to provide additional cooling of fluid flowing in first heat exchanger 16 from first solution inlet 22 and first solution outlet 24. A desilting basin may also be provided at an inlet of water pump 12 for settling out solid particles from the saltwater before it moves through system 10.

[0031] Referring to FIG. 1, a second heat exchanger 28 has a solvent inlet 30, a solvent outlet 32, a second solution inlet 34, and a second solution outlet 36. Solvent inlet 30 is in fluid communication with a solvent source 38 which includes a pump for moving solvent into system 10 through solvent inlet 30. Second solution outlet 36 is in fluid communication with first solution inlet 22 of first heat exchanger 16. The type of solvent used may vary depending upon user preference, however in a preferred embodiment, an ionic liquid directional solvent such as the ionic liquid solvent developed by the University of Notre Dame called {emim}[Tf2N] may be used. In the embodiment shown, second heat exchanger 28 is a helical coil heat exchanger, however it will be understood by a person skilled in the art that other types of heat exchangers may be used.

[0032] A swirl pump 40 is provided in fluid communication with saltwater outlet 20 of first heat exchanger 16 and solvent outlet 32 of second heat exchanger 28. In system 10, swirl pump 40 is a rim-driven impeller with a magnetic drive, however it will be understood by a person skilled in the art that any type of pump capable of mixing fluids together may be used. When three-way valve 26 is present and during start-up of system 10, saltwater is diverted back to water source 14. Once the preferred temperature of at least 40 degrees Celsius within vortex separator 54 is reached, three-way valve 26 directs heated saltwater to swirl pump 40. Heated saltwater and heated solvent are mixed together and the fluid is rotated by swirl pump 40 to create a saltwater / solvent mixture and enhance salt crystallization and heat exchange efficiency in a third heat exchanger 42. Swirl pump 40 also creates high shear mixing of the saltwater and solvent and creates rotation of the fluid. This may improve heat transfer efficiency in third heat exchanger 42 and may provide thorough mixing to improve crystallization which takes place within third heat exchanger 42.

[0033] A third heat exchanger 42 has a saltwater / solvent mixture inlet 44, a solution mixture outlet 46, a heated fluid inlet 48, and a cooled fluid outlet 50. Saltwater / solvent mixture inlet 44 is in fluid communication with swirl pump 40 such that the saltwater / solvent mixture is heated by third heat exchanger 42 which causes solvent to absorb water and becomes a solution and salts to crystallize prior to exiting through solution mixture outlet 46. A vortex breaker, not shown, may be positioned adjacent solution mixture outlet 46 to stop fluid from rotating and, thereby, reduce turbulence of fluid entering vortex separator 54. Vortex breaker may be installed inside of an outlet pipe of third heat exchanger 42 unless a pump is used. A person of skill would understand the appropriate placements and requirements for a vortex breaker. The fluid entering through heated fluid inlet 48 may come from any suitable source. In the embodiment shown, a heater 52 is provided upstream of heated fluid inlet 48 such that fluid is heated before entering third heat exchanger 42. In addition, heated fluid inlet 48 and cooled fluid outlet 50 may be set up as a closed loop such that a heating fluid circulates from heater 52 through heated fluid inlet 48, third heat exchanger 42, cooled fluid outlet 50, and back to heater 52. A pump 136 is provided to aid in heating fluid circulation. It will be understood by a person skilled in the art that any suitable heating fluid may be used in this closed system, including but not limited to water, glycol, oil, antifreeze, or any other known heat transfer fluids known in the art. A person of skill will also understand why types of pumps or other mechanisms may be used for heating fluid circulation. In the embodiment shown, third heat exchanger 42 is a helical coil heat exchanger, however it will be understood by a person skilled in the art that other types of heat exchangers may be used. Referring to FIG.9, a pump 136, such as a centrifugal solution pump, may be used to pump fluid from third heat exchanger 42 to vortex separator 54.

[0034] A vortex separator 54 has at least one solution vortex inlet 56 and a waste outlet 58. Vortex separator 54 may be a hydrocyclone separator that has an inlet chamber 62 positioned above a cyclone chamber 66. Solution vortex inlet(s) 56 are positioned such that fluid enters into inlet chamber 62. Inlet chamber 62 helps to reduce turbulence in vortex separator 54 which in turn helps to improve separation. Inlet chamber 62 further allows a return vortex 80 to flow parallel to an outer vortex 68 which further aids in separation. In the embodiment shown, two solution vortex inlets 56 are provided. Referring to FIG. 2, solution vortex inlets 56 are positioned adjacent a top 60 of vortex separator 54. When a pair of solution vortex inlets 56 are used, solution vortex inlets 56 are placed on opposed sides of an inlet chamber 62 adjacent top 60 of vortex separator 54. Where multiple solution vortex inlets 56 are used, solution vortex inlets 56 are distributed equidistant from each other around perimeter and adjacent top 60 of vortex separator 54. It will be understood by a person skilled in the art that a single solution vortex inlet 56 or multiple solution vortex inlets 56 may be used. Solution vortex inlets 56 are in fluid communication with solution mixture outlet 46 of third heat exchanger 42. Waste outlet 58 is positioned at a bottom 64 of vortex separator 54. It is preferably that waste outlet 58 be positioned at an apex at bottom 64 of vortex separator 54. Brine mixture, salt crystals, solvent / water solution and impurities may pass through waste outlet 58. As described above, cyclone chamber 66 is positioned below solution vortex inlets 56 and inlet chamber 62 and is used to create an outer vortex 68 traveling in a downward spiral adjacent a sidewall 70 of vortex separator 54 and an inner vortex 72 which travels in an upwardly direction from bottom 64 of vortex separator 54 to top 60 of vortex separator 54.Water / solvent solution and brine / salt crystal mixture entering vortex separator 54 are separated into a brine / salt crystal mixture and a water / solvent solution. Brine / salt crystal mixture moves to an outer portion of outer vortex 68 adjacent sidewall 70 as brine / salt crystal mixture is more dense and heavier than the water / solvent solution and, as a result, moves to the portion of outer vortex 68 closest to sidewall 70 due to centrifugal force. A vortex finder 74 is positioned at top 60 of vortex separator 54. Vortex finder 74 has a solution vortex outlet 76 in fluid communication with second solution inlet 34 of second heat exchanger 28. A portion of water / solvent solution from inner vortex 72 passes through solution vortex outlet 76 and a portion of water / solvent solution from inner vortex 72 is diverted back into cyclone chamber 66 by angled walls 78 of vortex finder 74 to create a return vortex 80. Return vortex 80 will mix back with inner vortex 72 such that water / solvent solution continues to circulate within cyclone chamber 66. Vortex separator 54 may have a built-in temperature sensor, not shown,controls inputs to maintain the temperature at operating levels. However, it will be understood by a person skilled in the art that other methods of taking temperature readings may be used by operators.

[0035] Referring to FIG. 1, an underflow pump 82 is provided in fluid communication with waste outlet 58 of vortex separator 54 and a sonic chamber 84. Underflow pump 82 draws the brine mixture and salt crystals from vortex separator 54 into sonic chamber 84. Referring to FIG.5 and FIG.8, sonic chamber 84 has at least one ultrasonic transducer 86 mounted on at least a portion of the perimeter 88 of sonic chamber 84. In the embodiment shown in FIG.8, three ultrasonic transducer arrays 86 are used.Ultrasonic transducers produce ultrasonic sound waves which create micro-mixing and complete salt crystallization from the remaining brine mixture. It will be understood by a person skilled in the art that a single ultrasonic transducer array or multiple ultrasonic transducer arrays may be used. Ultrasonic sound waves may also kill bacteria and algae and destroy perfluoroalkyl and polyfluoroalkyl substances and difficult to degrade organics. The sonic chamber has a sonic chamber waste outlet 90. In the embodiment shown in FIG. 6, underflow pump 82 has a magnetic drive 92 with a rotor 94 and stator 96. Rotor 94 includes an impeller 98 which, referring to FIG. 7, causes the brine / salt crystal mixture, identified with arrows pointing downwards in FIG. 7, to move downwards from underflow pump 82 into sonic chamber 84. The speed of rotation of brine / salt crystal mixture may be increased as it flows into sonic chamber 84. A displaced fluid solution, identified with an arrow pointing upwards in FIG. 7, travels up through a center of underflow pump 82 towards vortex separator 54, shown in FIG. 2, through waste outlet 58 and merges with inner vortex 72.

[0036] Referring to FIG.l and FIG.2, the water / solvent solution from vortex separator 54 travels through solution vortex outlet 76 and second solution inlet 34 of second heat exchanger 28 where the water / solvent solution is cooled by second heat exchanger 28 before exiting through second solution outlet 36 of second heat exchanger 28. Water / solvent solution flows through first solution inlet 22 of first heat exchanger 16 where the water / solvent solution is further cooled by first heat exchanger 16 to at or close to seawater temperature. As will be understood by a person skilled in the art, water / solvent solution traveling through first heat exchanger 16 and second heat exchanger 28 are used to heat saltwater and solvent, respectively. Referring to FIG. 1, a fluid-fluid separator 100 has a separator solution inlet 102, a solvent outlet 104, and a water outlet 106. Separator solution inlet 102 is in fluid communication with first solution outlet 24 of first heat exchanger 16. The cooled water / solvent solution is separated by fluid-fluid separator 100 into a separated solvent and a desalinated water, eachof which may be collected. The separated solvent may be reused within system 10. In the embodiment shown, fluid-fluid separator 100 is a parallel plate pack separator. Parallel plate pack separators are well known in the industry and will not be discussed in detail. Referring to FIG.4, a weir 108 is positioned between the solvent outlet 104 on a first side chamber 110 and water outlet 106 on a second side chamber 112. It will be understood by a person skilled in the art that any suitable fluid-fluid separator, such as API separators may be used. In the embodiment shown in FIG. 1, solvent may be stored in a separate storage tank 144 and moved between storage tank 144 and first side chamber 110 as needed to maintain an operating level of solvent within system 10. Storage tank 144 has a pump 136 for moving solvent out of storage tank 144 as needed. Referring to FIG.4, filters and strainers, not shown, may be installed at water outlet 106 and / or solvent outlet 104. Placing filters and strainers downstream of solvent source 38 may be beneficial. A person of skill will understand the proper placements of filters and strainers within system 10 to reduce risks of reducing pressure within system 10 through improper placement. Filters may aid in capturing any solvent that makes it to water outlet 106. Captured solvent may be recycled or reused within system 10. In the embodiment shown, solvent outlet 104 is in fluid communication with solvent source 38 to allow solvent to be reused within desalination system 10. It will be understood by a person skilled in the art that solvent may be disposed of after use or reused at the discretion of an operator. A level interface between solvent and water in first side chamber 110 is controlled to add solvent when the interface drops to a predetermined level. This may be accomplished through the use of a level switch, not shown, to add solvent when the interface between solvent and water drops to a predetermined level. This may be automated by system 10, a warning may be issued to an operator, or an operator may make a determination regarding solvent level manually.

[0037] Referring to FIG. 1, an elevated and vented chamber 132 may be positioned between and in fluid communication with first solution outlet 24 of first heat exchanger 16 and separator solution inlet 102 of fluid-fluid separator 100. Vented chamber 132 has a vent 134 that allows for gases to be released prior to fluid entering fluid-fluid separator 100. By elevating chamber 132, gas is vented at the highest elevation of system 10 and is used to prevent the build-up of gas within system 10. Gas within system 10 may cause issues with liquid flow. In addition, vented chamber 132 helps to prevent siphoning of liquid from vortex separator 54 to fluid-fluid separator 100 when system 10 is shut down.

[0038] A salt dump 114 may be provided for removal of salt through sonic chamber waste outlet 90. Salt dump 114 has a salt dump inlet 116, a salt outlet 118, a drain 120, and a fluid source inlet 122. Saltdump inlet 116 is in fluid communication with sonic chamber outlet 90 to allow salt crystals and brine mixture to be collected in salt dump 114. Salt crystals exiting through salt outlet 118 may be collected in a container, bin, on a conveyor, or by any other manner known to a person skilled in the art. Fluid source inlet 122 provides solution to salt dump 114 and vent air after salt is dumped. Drain 120 allows for the drainage of brine mixture and other fluid from salt dump 114 and salt outlet 118 allows for the collection of crystallized salts and other solid waste. In the embodiment shown in FIG.3, salt dump 114 has four chambers 124A, 124B, 124C, and 124D that are rotatable around an axis 126 in a first direction. Each of the four chambers is in one of four positions. The chamber in a first position is in communication with salt dump inlet 116. The chamber in a second position is in communication with drain 120. The chamber in a third position is in communication with salt outlet 118. The chamber in a fourth position is in communication with fluid source inlet 122. In the embodiment shown, chamber 124A is in the first position and is provided in fluid communication with sonic chamber outlet 90 for collection of salt crystals, waste, and brine mixture. Chamber 124B is in the second position and is in fluid communication with drain 120. Chamber 124C is in the third position and is in communication with salt outlet 118. When salt is removed or dumped through salt outlet 118, only air remains in chamber 124C. Chamber 124D is in the fourth position and in fluid communication with fluid source inlet 122. The chamber 124A in the first position has a level switch 128 that causes a 90 degree rotation towards drain 120 when triggered. When the 90 degree rotation occurs, brine mixture and other fluid from chamber 124A is drained through drain 120 leaving salt crystals and solid waste. Salt crystals and solid waste from chamber 124B is released through salt outlet 118 such that chamber 124B is filled with air while in third position. Empty chamber 124C is filled with solution and vents air while in fourth position. In the embodiment shown in FIG. 1, fluid source inlet 122 is in fluid communication with a salt dump outlet 130 on second heat exchanger 28 such that water / solvent solution from second heat exchanger 28 travels into inlet 122 while simultaneously venting air to second heat exchanger 28 through fluid source inlet 122 and salt dump outlet 130 prior to an additional 90 degree rotation that would move chamber 124C into first position. Without fluid source inlet 122, large amounts of air could enter vortex separator 54 through salt dump 114. Large amounts of air could negatively impact the efficiency of vortex separator 54.

[0039] Additional pumps 136 may be used throughout desalination system 10 to aid in maintaining the circulation of fluids through system. A person of skill will understand that some pumps 136 may be more useful than other pumps.

[0040] System 10 operates through fluid circulating to the various components of system 10.Movement through the system can be tracked as follows:a) Salt water is pumped from water source 14 through first heat exchanger 16 where the salt water is heated by recovered heat from fluid within system 10 during operation.b) A solvent is pumped from solvent source 38 through second heat exchanger 28 where it is heated by recovered heat from fluid within system 10 during operation.c) The heated salt water and the heated solvent are combined by swirl pump 40. This initiates brine mixture separation and crystallization of saltsd) The fluid flows into third heat exchanger 42 where it is heated to a preset operating temperature, as determined by the operator, by heating fluid.e) The fluid flows into vortex separator 54 and rotates down the perimeter inside vortex separator 54. The heavier salts and brine mixture migrate to the outer wall until it reaches bottom waste outlet 58.f) The lighter solution of water and solvent forms a central vortex that rises up the center of cyclone chamber 66 while the heavier liquid brine mixture and salt crystals are drawn down by underflow pump 82. Underflow pump 82 provides added rotation and downward velocity as the brine mixture and salt crystals move into sonic chamber 84.g) Sonic chamber 84 has ultrasonic transducers 86 which produce ultrasonic sound waves for micro-mixing and completion of crystallization as salt crystals settle through waste outlet 82 and into salt dump 114, when used. Salt can be separated using salt dump 114 or any other suitable device known to a person skilled in the art.h) Water / solvent solution that is displaced by the flow of fluid from underflow pump rises up the center of sonic chamber 84 and into cyclone chamber 66 of vortex separator 54 where it is combined with inner vortex 72.i) Inner vortex 72 rises to vortex finder 74 and through solution vortex outlet 76. Fluid passing through solution vortex outlet 76 is cooled by second heat exchanger 28 and first heat exchanger 16.j) The cooled fluid flows through vented chamber 132, when used, and into a fluid-fluid separator 100 for separation of desalinated water and solvent. When a parallel palate pack separator is used, water overflows weir 108 and is collected through water outlet 106.Collected desalinated water may be further treated as needed for domestic consumption or other uses. Solvent is collected through solvent outlet 104 and may be reused.

[0041] There are a number of potential benefits to utilizing system 10 over reverse osmosis. These include:1) System 10 has lower specific energy consumption and significantly reduces greenhouse gas emissions due to the low temperature desalination, low heat loss, as well as efficient heat exchange and heat recovery, and low operating pressure. The use of solar heating could potentially provide additional energy savings.2) System 10 has a lesser impact on coastal and marine ecosystems as there is no discharge of heated brine and chemicals, such as chlorine, back to the ocean.3) System 10 produces quality fresh water that contains many seawater nutrients without the use of chemicals or the need to reintroduce nutrients after desalination.4) System 10 separates mainly salt, instead of brine, for commercial and domestic consumption and mineral extraction.5) System 10 may have a lower cost for operation and maintenance compared to other desalination plants using other methodologies.6) System 10 may operate in a low energy resource setting.7) System 10 enables small scale desalination. It is possible that system 10 could be utilized to provide fresh water for ships.

[0042] Any use herein of any terms describing an interaction between elements is not meant to limit the interaction to direct interaction between the subject elements, and may also include indirect interaction between the elements such as through secondary or intermediary structure unless specifically stated otherwise.

[0043] In this patent document, the word "comprising" is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article "a" does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements.

[0044] It will be apparent that changes may be made to the illustrative embodiments, while falling within the scope of the invention. As such, the scope of the following claims should not be limited by the preferred embodiments set forth in the examples and drawings described above, but should be given the broadest interpretation consistent with the description as a whole.

Claims

CLAIMSWhat is claimed is:

1. A desalination system, comprising:a water pump for pumping saltwater from a water source;a first heat exchanger having a saltwater inlet, a saltwater outlet, a first solution inlet and a first solution outlet, the saltwater inlet in fluid communication with the water pump;a second heat exchanger having a solvent inlet, a solvent outlet, a second solution inlet and a second solution outlet, the solvent inlet in fluid communication with a solvent source, the second solution outlet in fluid communication with the first solution inlet;a swirl pump is in fluid communication with the saltwater outlet of the first heat exchanger and the solvent outlet of the second heat exchanger such that a heated saltwater from the first heat exchanger and a heated solvent from the second heat exchanger are mixed together by the swirl pump to create a saltwater / solvent mixture;a third heat exchanger having a saltwater / solvent mixture inlet, a solution mixture outlet, a heated fluid inlet and a cooled fluid outlet, the saltwater / solvent mixture inlet being in fluid communication with the swirl pump such that the saltwater / solvent mixture is heated by the third heat exchanger such that the solvent absorbs water to become a solvent / water solution, salt is crystallized, and a brine mixture is formed;a vortex separator having an inlet chamber and a cyclone chamber, at least one solution vortex inlet and a waste outlet, the at least one solution vortex inlet being in fluid communication with the solution mixture outlet of the third heat exchanger, the at least one solution vortex inlets being positioned adjacent a top of the vortex separator as a tangential connection into the inlet chamber, the waste outlet being positioned at a bottom of the vortex separator, the cyclone chamber being positioned below the inlet chamber, the cyclone chamber creating an outer vortex and an inner vortex to separate the brine mixture and a water / solvent solution, the brine mixture being moved to the outer vortex, the water / solvent solution being moved to the inner vortex rising up a center of the cyclone chamber to a vortex finder positioned at the top of the vortex separator, the vortex finder having a solution vortex outlet in fluid communication with the second solution inlet, a portion of the water / solvent solution from the inner vortex passing through the solution vortex outlet and a portion of the water / solvent solution from the inner vortex being diverted back down the cyclone chamber to forma return vortex, the return vortex mixing with the inner vortex and rising upwards through a center of the cyclone chamber;an underflow pump in fluid communication with the waste outlet of the vortex separator and a sonic chamber, the underflow pump drawing the brine mixture and salt crystals from the vortex separator into the sonic chamber, the sonic chamber having at least one ultrasonic transducer array mounted on at least a portion of a perimeter of the sonic chamber, the at least one ultrasonic transducers producing ultrasonic sound waves, the ultrasonic sound waves completing salt crystallization of the brine mixture, the sonic chamber having a sonic chamber waste outlet and a sonic chamber solution outlet, the sonic chamber waste outlet allowing for the removal of salt crystals and the brine mixture, the sonic chamber solution outlet being in fluid communication with a center of the underflow pump such that the sonic chamber solution outlet is in fluid communication with the cyclone chamber;a salt dump for removal of salt through the sonic chamber waste outlet; anda fluid-fluid separator having a separator solution inlet, a solvent outlet and a water outlet, the separator solution inlet being in fluid communication with the first solution outlet of the first heat exchanger, the water / solvent solution being separated into a separated solvent and a desalinated water.

2. The desalination system of claim 1 wherein the salt dump has a salt dump inlet, a salt outlet, a drain and a fluid source inlet, the salt dump inlet being in fluid communication with the sonic chamber outlet.

3. The desalination system of claim 2 wherein the salt dump has four chambers rotatable on an axis in a first direction, each of the four chambers being in one of four positions, in a first position a first of the four chambers is in fluid communication with the sonic chamber outlet for collection of salt crystals and waste, in a second position a second of the four chambers is in fluid communication with the drain, in a third position a third of the four chambers is in communication with the salt outlet, and in a fourth position a fourth of the four chambers is in fluid communication with the fluid source inlet, a level switch being positioned in the chamber in the first position such that triggering of the level switch causes a 90 degree rotation of the four chambers in the first direction towards the drain.

4. The desalination system of claim 3 wherein the second heat exchanger has a salt dump outlet in fluid communication with the salt dump such that fluid from the second heat exchanger flows through thesalt dump outlet to the salt dump through the fluid source inlet to fill the fourth of the four chambers in the fourth position with fluid and vent gases within the salt dump during rotation of the four chambers.

5. The desalination system of claim 1 wherein there is a pair of solution mixture vortex inlets, the pair of solution mixture vortex inlets being positioned on opposed sides of an inlet chamber adjacent the top of the vortex separator.

6. The desalination system of claim 1 wherein the first heat exchanger, the second heat exchanger and the third heat exchanger are helical coil heat exchangers.

7. The desalination system of claim 1 wherein the fluid-fluid separator is a parallel plate pack separator, the solvent outlet being on a first side chamber of a weir and the water outlet being on a second side chamber of the weir.

8. The desalination system of claim 1 wherein the desalinated water has no more than 1 gram per liter of salt content.

9. The desalination system of claim 1 wherein the underflow pump comprises a magnetic drive having a rotor and a stator, the rotor being connected to an impeller, rotation of the impeller causing the brine mixture to move downwards and to a perimeter of the sonic chamber, a displaced solution traveling upwards through a center of the underflow pump towards the vortex separator, the displaced solution merging with the inner vortex.

10. The desalination system of claim 1 further comprising an elevated and vented chamber positioned between and in fluid communication with the first solution outlet of the first heat exchanger and the separator solution inlet of the fluid-fluid separator.

11. The desalination system of claim 1 further comprising a heater positioned upstream of the heated fluid inlet of the third heat exchanger for heating fluid flowing through the third heat exchanger.

12. The desalination system of claim 11 wherein the heated fluid inlet of the third heat exchanger and the cooled fluid outlet of the third heat exchanger are a closed loop such that a heating fluid circulates in the closed loop.

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