Device and method for distilling seawater under negative pressure

Abstract

The invention belongs to the technical field of seawater desalination, and discloses a negative-pressure seawater distillation device and a method thereof.The negative-pressure seawater distillation device comprises a lower shell, a water storage tank is fixedly installed below the lower shell, an upper shell is installed above the lower shell in a sealed mode through a sealing assembly, and a distillation chamber is arranged in the upper shell and the lower shell; a fresh water tank is arranged on the inner surface of the lower shell close to the upper part of the lower shell, a centrifugal fog making assembly is arranged below the fresh water tank in the distillation chamber, a water spraying head is arranged right above the centrifugal fog making assembly, a seawater conveying pipeline for conveying seawater to the water spraying head is arranged on the outer side of the lower shell, and a vacuumizing pipeline is arranged above the upper shell; according to the negative pressure distillation principle, seawater can generate a large amount of water vapor, fresh water is obtained by condensing the water vapor, the overall energy consumption is small, a large amount of high-quality pure fresh water can be produced, and the use effect is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of seawater desalination, and in particular relates to a negative pressure seawater distillation device and a method thereof. Background Art

[0002] Desalination is the production of fresh water by desalinating seawater. It is an open-source incremental technology for realizing water resource utilization. It can increase the total amount of fresh water and is not affected by time, space and climate. It can ensure a stable water supply for drinking water for coastal residents and water replenishment for industrial boilers. The desalination methods currently used include seawater freezing, electrodialysis, distillation, reverse osmosis, and ammonium carbonate ion exchange. Currently, the application of reverse osmosis membrane method and distillation method are the mainstream in the market.

[0003] Among them, the reverse osmosis membrane method uses an osmotic membrane to filter seawater to produce fresh water; however, this type of existing reverse osmosis membrane method requires the replacement of filter membranes and other materials at regular intervals, which is not only expensive but also affects the normal production of fresh water.

[0004] The distillation method uses a variety of heating methods to heat seawater to generate water vapor to obtain distilled fresh water. The structure of the distillation method is various. The Chinese patent with patent application number: CN201310300526.7 discloses a vacuum steam compression distillation seawater desalination device, including: a seawater pump, a sealed chamber, a vacuum evaporation chamber and a vacuum pump and other components; during operation, the shaft drives the vacuum evaporation chamber filled with fresh water to rotate, and then seawater is introduced into the vacuum water-free area. At the same time, working steam is introduced into the steam coil. The steam in the steam coil exchanges heat with the seawater outside it, so that the steam condenses to obtain fresh water and the seawater evaporates to obtain primary steam. The primary steam is compressed by an impeller to increase the temperature and pressure and enter the steam coil to act as working steam. Continuous steam compression distillation realizes seawater desalination.

[0005] The above-mentioned existing distillation desalination device of this type has achieved fresh water by heating seawater, but this type of existing distillation desalination device consumes a lot of energy in the process of distilling seawater, resulting in high production and use costs, and the overall structure is complex. The amount of water vapor generated in the heating process of seawater is small, resulting in low fresh water production efficiency. Summary of the invention

[0006] The main technical problem to be solved by the present invention is to provide a negative pressure distillation seawater device and method thereof, which can utilize the negative pressure distillation principle that seawater produces a large amount of water vapor, and obtain fresh water by condensing the water vapor. The overall energy consumption is small, and a large amount of high-quality pure fresh water can be produced, thereby improving the use effect.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: A negative pressure seawater distillation device comprises a lower shell, a water storage tank is fixedly installed below the lower shell, an upper shell is sealed and installed above the lower shell through a sealing assembly, a distillation chamber is arranged inside the upper shell and the lower shell, a fresh water tank is arranged on the inner surface of the lower shell near the upper position thereof, a centrifugal mist-making assembly is arranged below the fresh water tank in the distillation chamber, a water spray head is arranged directly above the centrifugal mist-making assembly, a seawater conveying pipeline for conveying seawater to the water spray head is arranged on the outer side of the lower shell, and a vacuum pipeline is arranged above the upper shell.

[0008] The following is a further optimization of the above technical solution by the present invention: The vacuum pipeline is used to evacuate the distillation chamber, and the vacuum degree in the distillation chamber is 1KPa-10KPa. The seawater delivery pipeline is used to heat the external seawater and then deliver it to the sprinkler head and spray it out. The inlet temperature of the seawater is 30℃-50℃.

[0009] Further optimization: the centrifugal mist-making assembly includes an elevated cylinder platform, which is coaxially and fixedly installed on the inner bottom surface of the water tank, a supporting sleeve is fixedly installed above the elevated cylinder platform, and a rotating shaft is coaxially installed in the supporting sleeve; the upper end of the rotating shaft extends to the top of the supporting sleeve and is fixedly installed with a centrifugal disk, the lower end of the rotating shaft passes through the elevated cylinder platform and is transmission-connected to a high-speed motor, and the high-speed motor is fixedly installed in the elevated cylinder platform.

[0010] Further optimization: the cross section of the centrifugal disk is an arc-shaped disk structure, the upper end surface of the centrifugal disk is located below the upper edge of the fresh water tank, and the high-speed rotation of the centrifugal disk is used to disperse the high-temperature seawater sprayed from the sprinkler head, so that the seawater is rapidly atomized under the action of flash evaporation, and the high-temperature seawater dispersed by the centrifugal disk is located below the fresh water tank and will not be thrown into the fresh water tank.

[0011] Further optimization: the seawater delivery pipeline includes a metal universal tube, which is fixedly installed on the elevated cylinder platform, the upper end of the metal universal tube is connected to the sprinkler head, the other end of the metal universal tube is located in the elevated cylinder platform and is connected to a water inlet pipe, and the other end of the water inlet pipe is connected to the seawater source; a first reversing valve, a flow switch and a heater are connected in series on the water inlet pipe in the direction of the seawater flow.

[0012] Further optimization: a concentrated brine tank is arranged outside the lower shell, a concentrated brine return pipeline is arranged between the concentrated brine tank and the water storage tank, a first one-way valve and a concentrated brine return pump are connected in series in sequence along the flow direction of coastal water on the concentrated brine return pipeline, and a reflux pipeline is arranged between the concentrated brine tank and the first reversing valve.

[0013] Further optimization: the lower shell is connected with a fresh water output pipeline, one end of which passes through the outer surface of the lower shell and is connected with the fresh water tank; the other end of the fresh water output pipeline is connected with a first fresh water tank, and a first fresh water pump is connected in series on the fresh water output pipeline.

[0014] Further optimization: one end of the vacuum pipeline passes through the upper shell and is connected to the distillation chamber, the other end of the vacuum pipeline is connected to the second fresh water tank, and the second one-way valve, the second reversing valve and the condenser are connected in series in the air flow direction on the vacuum pipeline; the second reversing valve is also connected to an exhaust pipe, and the other end of the exhaust pipe is connected to a switch valve; A vacuum pump is connected in parallel on the vacuum pumping pipeline between the second one-way valve and the second reversing valve, and an air outlet of the vacuum pump is communicated with an exhaust pipe between the second reversing valve and the switch valve.

[0015] Further optimization: a cooling assembly is installed on the outer surface of the upper shell, the cooling assembly includes a cooling jacket, the cooling jacket is fixedly installed on the outer surface of the upper shell, the water inlet of the cooling jacket is connected to a cooling water inlet pipe, the other end of the cooling water inlet pipe is connected to a seawater source, a cooling water pump is connected in series to the cooling water inlet pipe, and the water outlet of the cooling jacket is connected to a cooling water return pipe.

[0016] The present invention also provides a method for distilling seawater under negative pressure. Based on the above-mentioned device for distilling seawater under negative pressure, the method is carried out according to the following steps: Step 1: First, open the second reversing valve and the switch valve, and start the vacuum pump to evacuate the second fresh water tank and the distillation chamber. When the vacuum degree in the distillation chamber reaches 1KPa-10KPa, turn on the flow switch and the heater. The heater is used to heat the seawater so that the inlet temperature of the seawater is 30℃-50℃. At this time, the seawater in the seawater source is transported to the sprinkler head through the water inlet pipe and the metal universal pipe and sprayed out. Step 2: Start the high-speed motor of the centrifugal mist-making component to drive the rotating shaft to drive the centrifugal disk to rotate at high speed. The high-temperature seawater sprayed by the water spray head falls on the centrifugal disk. The centrifugal disk rotates at high speed to scatter the seawater, so that the seawater is rapidly atomized under the action of flash evaporation. At this time, the liquid seawater drips into the water storage tank, and the atomized water vapor rises. When the water vapor contacts the inner surface of the upper shell, the water vapor condenses into liquid water droplets on the inner surface of the upper shell. The liquid water droplets slide along the inner surface of the upper shell into the fresh water tank under the action of gravity; Step 3: Then close the switch valve and switch the working state of the second reversing valve, so that the gas discharged during the vacuum pumping process is transported to the condenser through the second reversing valve. At this time, the condenser is used to condense the moisture in the gas flowing through to form fresh water and transport it to the second fresh water tank; Step 4: The cooling water pump of the cooling assembly is used to suck seawater from the seawater source and transport it to the cooling jacket through the cooling water inlet pipe; the seawater flowing in the cooling jacket is used to cool the upper shell to improve the condensation effect of the upper shell on water vapor; the seawater in the cooling jacket is discharged through the cooling water return pipe; Step 5: The first fresh water pump on the fresh water output pipeline is used to pump the fresh water in the fresh water tank and transport it to the first fresh water tank; Step 6: When the seawater in the water storage tank reaches the highest liquid level, the concentrated salt return pump on the concentrated salt return pipeline is used to suck the seawater in the water storage tank and transport it to the concentrated salt water tank; Step 7: When the seawater refluxed in the concentrated brine tank can still be used, the first reversing valve is controlled to work so that the reflux pipeline is connected to the water inlet pipe. At this time, the seawater in the concentrated brine tank is transported to the water inlet pipe through the reflux pipeline, and the seawater is heated by the heater and then sprayed out through the sprinkler head; Step 8: Then collect the fresh water obtained in the first fresh water tank and the second fresh water tank.

[0017] The present invention adopts the above technical scheme, which has ingenious conception and reasonable structure. It can utilize the negative pressure distillation principle that seawater produces a large amount of water vapor, and obtain fresh water by condensing the water vapor. The overall energy consumption is small, and a large amount of high-quality pure fresh water can be produced, thereby improving the use effect.

[0018] The present invention is further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the overall structure of Example 1 of the present invention; Figure 2 for Figure 1 A partial enlarged view of the middle A; Figure 3 This is a schematic diagram of the structure of the centrifugal mist-making assembly in Example 1 of the present invention; Figure 4 This is a schematic diagram of the overall structure of Example 2 of the present invention.

[0020] In the figure: 1-upper shell; 101-fixed folding edge; 102-clamping hoop; 103-tightening bolt; 104-sealing pad; 2-lower shell; 201-fresh water tank; 202-liquid level gauge; 3-water storage tank; 4-seawater delivery pipeline; 401-water inlet pipe; 402-metal universal pipe; 403-first reversing valve; 404-flow switch; 405-heater; 406-filter; 407-return pipeline; 408-water inlet pump; 409-series pipe; 5-centrifugal mist making component; 501-heightened cylinder platform; 502-support sleeve; 503-rotating shaft; 504-high-speed motor; 505-centrifugal disc; 506-rotating seal; 507-high-speed bearing; 6-sprinkler head; 7-vacuum pipeline; 701-second fresh water tank; 702-second one-way valve; 703-second reversing valve valve; 704-condenser; 705-exhaust pipe; 706-on-off valve; 707-vacuum pump; 708-vacuum pressure gauge; 709-water inlet cooling pipe; 8-cooling assembly; 801-cooling jacket; 802-cooling water inlet pipe; 803-cooling water pump; 804-cooling return pipe; 805-spray ring pipe; 806-water collecting tank; 9-concentrated salt return pipe; 901-concentrated salt return Pump; 902-first one-way valve; 10-fresh water output pipeline; 1001-first fresh water tank; 1002-first fresh water pump; 1003-fresh water pipe; 1004-normal pressure fresh water tank; 1005-third one-way valve; 1006-second fresh water pump; 1007-fresh water delivery pipe; 1008-fourth one-way valve; 1009-third fresh water pump; 11-distillation chamber; 12-concentrated brine tank. DETAILED DESCRIPTION

[0021] Example 1: Figure 1-3 As shown: a negative pressure seawater distillation device comprises a lower shell 2, a water storage tank 3 is fixedly installed below the lower shell 2, an upper shell 1 is sealed and installed above the lower shell 2 through a sealing assembly, a distillation chamber 11 is arranged inside the upper shell 1 and the lower shell 2, a fresh water tank 201 is arranged on the inner surface of the lower shell 2 near the upper position thereof, a centrifugal mist-making assembly 5 is arranged below the fresh water tank 201 in the distillation chamber 11, a water spray head 6 is arranged directly above the centrifugal mist-making assembly 5, a seawater conveying pipeline 4 for conveying seawater to the water spray head 6 is arranged on the outer side of the lower shell 2, a vacuum pipeline 7 is arranged above the upper shell 1, and the vacuum pipeline 7 is used to vacuum the distillation chamber 11.

[0022] In the present embodiment 1, the vacuum pumping pipeline 7 is used to evacuate the distillation chamber 11 so that the vacuum degree in the distillation chamber 11 is between 1KPa and 10KPa. The seawater delivery pipeline 4 is used to heat the seawater after sucking the external seawater to 30°C-50°C, and then deliver it to the water spray head 6 for spraying after pressurization. At this time, the centrifugal mist making component 5 works to rotate its working end at a high speed, and disperses the seawater sprayed from the water spray head 6, so that the seawater is atomized to produce a large amount of water vapor. The salty seawater flows back to the water storage tank 3 under the action of gravity. At this time, the water vapor flows upward. When the water vapor contacts the inner surface of the upper shell 1, the water vapor condenses into liquid water droplets on the inner surface of the upper shell 1. The liquid water droplets slide along the inner surface of the upper shell 1 under the action of gravity into the fresh water tank 201. At this time, the fresh water tank 201 is used to temporarily store the fresh water.

[0023] In this embodiment 1, the upper shell 1 is in a conical shape and is made of stainless steel material resistant to seawater corrosion.

[0024] In this embodiment 1, the water tank 3 and the lower shell 2 are coaxially arranged, and the outer surface of the water tank 3 is a cylindrical surface; the outer surface of the lower shell 2 is a conical surface; the water tank 3 and the lower shell 2 are also made of stainless steel material resistant to seawater corrosion.

[0025] The outer surface of the lower shell 2 is provided with a heat-insulating layer, which is used to insulate the lower shell 2 and prevent the heat on the lower shell 2 from leaking out.

[0026] In this embodiment 1, the distillation chamber 11 needs to be evacuated. In order to ensure the overall structural strength of the upper shell 1, the lower shell 2 and the water tank 3, reinforcing rib components can be installed on the inner surface or outer surface of the upper shell 1, the lower shell 2 and the water tank 3. The reinforcing rib components are used to improve the overall structural strength of the negative pressure seawater distillation device to avoid deformation of the overall structure of the upper shell 1, the lower shell 2 and the water tank 3 when the vacuum is drawn.

[0027] In the present embodiment 1, the fresh water tank 201 is in the shape of an annular tank, and the fresh water tank 201 is arranged in an annular shape along the inner surface of the lower shell 2 , and the fresh water tank 201 and the distillation chamber 11 are arranged coaxially.

[0028] The sealing assembly includes a fixed folded edge 101 integrally connected to the outer surface of the upper shell 1 and the lower shell 2 on one side close to each other, a sealing gasket 104 is arranged between the side surfaces of the two fixed folded edges 101 close to each other, and the connection between the two fixed folded edges 101 is sealed by the sealing gasket 104.

[0029] The outer sides of the two fixed flanges 101 are sleeved with a clamp 102 , and the cross section of the clamp 102 is a U-shaped groove; the clamp 102 is threadedly connected with a tightening bolt 103 , and one end of the tightening bolt 103 is in contact with the corresponding fixed flange 101 .

[0030] When assembling the upper shell 1 and the lower shell 2, the fixed folded edge 101 on the upper shell 1 is connected with the fixed folded edge 101 on the lower shell 2, and a sealing gasket 104 is provided between the two fixed folded edges 101, and the sealing gasket 104 is used to seal the connection between the two fixed folded edges 101, and then the clamp 102 is sleeved on the outside of the fixed folded edge 101, and the tightening bolt 103 on the clamp 102 is tightened so that the tightening bolt 103 is in contact with the corresponding fixed folded edge 101. At this time, the two fixed folded edges 101 are sealed and fixedly connected through the cooperation of the clamp 102, the tightening bolt 103 and the sealing gasket 104.

[0031] And in the present embodiment 1, the distillation chamber 11 needs to be evacuated. At this time, as long as the two fixed folded edges 101 of the upper shell 1 and the lower shell 2 are tightly connected, the connection between the upper shell 1 and the lower shell 2 can be sealed by the negative pressure suction when the distillation chamber 11 is evacuated.

[0032] The centrifugal mist-making component 5 includes a raised cylinder platform 501, which is coaxially arranged with the distillation chamber 11 and fixedly mounted on the inner bottom surface of the water storage tank 3. A support sleeve 502 is fixedly mounted above the raised cylinder platform 501, and a rotating shaft 503 is coaxially mounted inside the support sleeve 502.

[0033] The upper end of the rotating shaft 503 extends to the top of the supporting sleeve 502 and is fixedly mounted with a centrifugal disc 505 . The lower end of the rotating shaft 503 passes through the elevated cylinder platform 501 and is transmission-connected with a high-speed motor 504 . The high-speed motor 504 is fixedly mounted in the elevated cylinder platform 501 .

[0034] The high-speed motor 504 is used to drive the rotating shaft 503 to rotate, and the rotation of the rotating shaft 503 drives the centrifugal disk 505 to rotate at a high speed.

[0035] In this embodiment 1, the cross section of the centrifugal disc 505 is an arc-shaped disc structure.

[0036] A spacing distance is set between the upper end surface of the centrifugal disc 505 and the upper edge surface of the fresh water tank 201 , and the upper end surface of the centrifugal disc 505 is located below the upper edge surface of the fresh water tank 201 .

[0037] With such a design, the high-temperature seawater sprayed by the water spray head 6 falls on the centrifugal disk 505. At this time, the high-speed motor 504 works to drive the centrifugal disk 505 to rotate at a high speed. At this time, the centrifugal disk 505 is used to disperse the high-temperature seawater, so that the high-temperature seawater generates a large amount of water vapor, and the water vapor rises and flows toward the upper chamber of the distillation chamber 11.

[0038] In addition, the upper end surface of the centrifugal disk 505 is located below the upper edge surface of the fresh water tank 201. At this time, the high-temperature seawater dispersed by the centrifugal disk 505 is located below the fresh water tank 201 and will not be thrown into the fresh water tank 201, thereby preventing salty seawater from entering the fresh water tank 201 and contaminating the fresh water, thereby improving the quality of the fresh water in the fresh water tank 201 and improving the use effect.

[0039] The high-temperature seawater sprayed by the water spray head 6 falls on the high-speed rotating centrifugal disk 505. At this time, the cooperation between the water spray head 6 and the high-speed rotating centrifugal disk 505 can disperse the high-temperature seawater, improve the evaporation efficiency of the seawater, and make the high-temperature seawater generate a large amount of water vapor.

[0040] A rotary seal 506 is sleeved on the rotating shaft 503 in the support sleeve 502, and the rotary seal 506 is used to seal the connection between the rotating shaft 503 and the support sleeve 502, thereby improving the use effect. A plurality of high-speed bearings 507 for supporting the rotating shaft 503 for rotation are also installed in the supporting sleeve 502. The cooperation between the supporting sleeve 502 and the high-speed bearings 507 is used to improve the stability of the rotating shaft 503 during high-speed rotation and improve the use effect.

[0041] The seawater delivery pipeline 4 includes a metal universal tube 402, which is fixedly mounted on the elevated cylinder platform 501, the upper end of the metal universal tube 402 is connected to the sprinkler head 6, the other end of the metal universal tube 402 is located in the elevated cylinder platform 501 and is connected to the water inlet pipe 401, and the other end of the water inlet pipe 401 is connected to the seawater source.

[0042] In addition to the present embodiment 1, the metal universal tube 402 can also be made by bending a metal tube.

[0043] The water inlet pipe 401 is connected in series with a first reversing valve 403 , a flow switch 404 , and a heater 405 in sequence along the flow direction of the coastal water.

[0044] The flow switch 404 is used to control the flow of seawater in the water inlet pipe 401, and the heater 405 is used to heat the seawater in the water inlet pipe 401 to turn the seawater into high-temperature seawater.

[0045] In this embodiment 1, the distillation chamber 11 is evacuated by the vacuum pipe 7. At this time, the distillation chamber 11 is in a vacuum state, and the vacuum negative pressure acts on the water spray head 6 to suck the seawater from the water spray head 6, thereby enabling the water inlet pipe 401 to achieve automatic transportation operation.

[0046] In this embodiment 1, a filter 406 is installed on one end of the water inlet pipe 401 that is connected to the seawater source.

[0047] A liquid level meter 202 is also installed on the outer surface of the lower shell 2 , and the liquid level meter 202 is used to detect the liquid level of the liquid seawater in the lower shell 2 .

[0048] In this embodiment 1, the flow switch 404 is an automatic switch, which is used to automatically adjust the delivery flow rate of seawater in the water inlet pipe 401. The flow switch 404 is controlled and connected to the liquid level meter 202, and the opening of the flow switch 404 is automatically controlled by the detection signal of the liquid level meter 202. When the liquid level detected by the liquid level meter 202 increases, the opening of the flow switch 404 decreases; when the liquid level detected by the liquid level meter 202 decreases, the opening of the flow switch 404 increases.

[0049] In this embodiment 1, the technology for controlling the connection between the flow switch 404 and the liquid level meter 202 is prior art and will not be described in detail here.

[0050] In addition to the present embodiment 1, the flow switch 404 may also be a manual flow switch, and the user can manually control the opening of the flow switch 404 to adjust the flow rate of seawater in the water inlet pipe 401 .

[0051] A concentrated brine tank 12 is disposed outside the lower shell 2 , a concentrated brine return pipeline 9 is disposed between the concentrated brine tank 12 and the water storage tank 3 , and a reflux pipeline 407 is disposed between the concentrated brine tank 12 and the first reversing valve 403 .

[0052] One end of the concentrated salt return pipeline 9 is connected to the water outlet of the concentrated salt water tank 12, and the other end of the concentrated salt return pipeline 9 is connected to the concentrated salt water tank 12. A first one-way valve 902 and a concentrated salt return pump 901 are connected in series in sequence along the flow direction of coastal water on the concentrated salt return pipeline 9.

[0053] The first one-way valve 902 is used to perform one-way control on the flow direction of the concentrated salt return pipeline 9 to prevent the seawater in the concentrated salt return pipeline 9 from flowing back into the water storage tank 3 .

[0054] With this design, when the seawater in the water storage tank 3 reaches the highest liquid level, the concentrated brine return pump 901 works through the concentrated brine return pipeline 9 to suck the liquid seawater in the water storage tank 3 and transport it to the concentrated brine tank 12. At this time, the concentrated brine tank 12 is used to temporarily store the concentrated brine.

[0055] In this embodiment, the first reversing valve 403 has two working positions. When the first reversing valve 403 is located at the first working position, the water inlet pipe 401 is connected to the seawater source. At this time, the water inlet pipe 401 is used to suck seawater in the seawater source and transport it to the sprinkler head 6 for spraying; when the first reversing valve 403 is located at the second working position, the water inlet pipe 401 is connected to the return pipe 407 through the first reversing valve 403. At this time, the water inlet pipe 401 is used to suck seawater in the concentrated brine tank 12 through the return pipe 407, so as to reuse the seawater in the concentrated brine tank 12.

[0056] After the seawater in the concentrated brine tank 12 is refluxed multiple times and evaporated to prepare water vapor, the water content in the concentrated brine tank 12 will be relatively reduced, thereby increasing the salt concentration of the seawater in the concentrated brine tank 12. At this time, the concentrated brine seawater in the concentrated brine tank 12 can be transported out for processing and transported to a sea salt manufacturer for preparing sea salt.

[0057] The lower shell 2 is connected with a fresh water output pipeline 10, one end of which passes through the outer surface of the lower shell 2 and is connected with the fresh water tank 201; the other end of the fresh water output pipeline 10 is connected with a first fresh water tank 1001, and the fresh water output pipeline 10 is connected in series with a first fresh water pump 1002.

[0058] The first fresh water pump 1002 is used to pump fresh water in the fresh water tank 201 through the fresh water output pipeline 10 and transport it to the first fresh water tank 1001. At this time, the first fresh water tank 1001 is used to store fresh water.

[0059] One end of the vacuum pipeline 7 passes through the upper shell 1 and is connected to the distillation chamber 11, and the other end of the vacuum pipeline 7 is connected to the second fresh water tank 701. The vacuum pipeline 7 is connected in series with a second one-way valve 702, a second reversing valve 703 and a condenser 704 in sequence along the flow direction of air.

[0060] The second reversing valve 703 is also connected to an exhaust pipe 705 , and the other end of the exhaust pipe 705 is connected to a switch valve 706 .

[0061] A vacuum pump 707 is connected in parallel on the vacuum pumping pipeline 7 between the second one-way valve 702 and the second reversing valve 703 , and an outlet end of the vacuum pump 707 is connected to an exhaust pipe 705 between the second reversing valve 703 and the switch valve 706 .

[0062] In this embodiment, the switch valve 706 has two positions, namely an open position and a closed position. When the switch valve 706 is in the closed position, the switch valve 706 is in a closed state. At this time, the switch valve 706 is used to close the exhaust end of the exhaust pipe 705; when the switch valve 706 is in the open position, the switch valve 706 is in an open state. At this time, the air exhausted by the vacuum pump 707 is discharged through the exhaust pipe 705.

[0063] In this embodiment, the second reversing valve 703 has two positions, namely, a steam delivery position and a fresh water tank vacuuming position; when the second reversing valve 703 is at the steam delivery position, the vacuum pump 707 works to vacuum the distillation chamber 11 through the vacuuming pipeline 7, and the gas extracted from the distillation chamber 11 is transported to the second fresh water tank 701 through the second one-way valve 702, the second reversing valve 703, and the condenser 704; At this time, when there is water vapor in the distillation chamber 11 , the water vapor flows into the condenser 704 along with the air flow. The condenser 704 is used to condense the water vapor to obtain fresh water, and the fresh water is transported to the second fresh water tank 701 .

[0064] When the second reversing valve 703 is at the fresh water tank vacuum pumping position, the switch valve 706 cooperates and switches to the open position; at this time, one end of the vacuum pumping pipeline 7 is connected to the distillation chamber 11, and the other end of the vacuum pumping pipeline 7 is also connected to the second fresh water tank 701. At this time, the vacuum pump 707 works through the vacuum pumping pipeline 7 to synchronously vacuum the distillation chamber 11 and the second fresh water tank 701, so that a vacuum state is also formed in the second fresh water tank 701; and the gas discharged by the vacuum pump 707 is discharged through the exhaust pipe 705.

[0065] A vacuum pressure gauge 708 is fixedly mounted on the top of the upper shell 1 , and the vacuum pressure gauge 708 is used to detect the vacuum degree in the distillation chamber 11 .

[0066] The water outlet of the second fresh water tank 701 is connected with a fresh water pipe 1003 , and the other end of the fresh water pipe 1003 is connected with a normal pressure fresh water tank 1004 . The fresh water pipe 1003 is connected in series with a third one-way valve 1005 and a second fresh water pump 1006 in the direction of water flow.

[0067] The third one-way valve 1005 is used to perform one-way control on the flow direction of the fresh water pipe 1003 to prevent the fresh water in the fresh water pipe 1003 from flowing back into the second fresh water tank 701 .

[0068] The second fresh water pump 1006 is used to pump fresh water in the second fresh water tank 701 and transport it to the normal pressure fresh water tank 1004 through the fresh water pipe 1003 .

[0069] A fresh water delivery pipe 1007 is provided between the first fresh water tank 1001 and the normal pressure fresh water tank 1004 , and both ends of the fresh water delivery pipe 1007 are respectively connected to the corresponding first fresh water tank 1001 and the normal pressure fresh water tank 1004 .

[0070] The fresh water delivery pipe 1007 is serially connected with a fourth one-way valve 1008 and a third fresh water pump 1009 in sequence along the water flow direction.

[0071] The fourth one-way valve 1008 is used to perform one-way control on the flow direction of the fresh water delivery pipe 1007 to prevent the fresh water in the fresh water delivery pipe 1007 from flowing back to the first fresh water tank 1001 .

[0072] The third fresh water pump 1009 is used to pump fresh water in the first fresh water tank 1001 and transport it to the normal pressure fresh water tank 1004 through the fresh water delivery pipe 1007 . At this time, the fresh water prepared by the negative pressure seawater distillation device is collected in the normal pressure fresh water tank 1004 .

[0073] A cooling assembly 8 is installed on the outer surface of the upper shell 1, and the cooling assembly 8 is used to cool the upper shell 1, so that the upper shell 1 can better condense the water vapor in the distillation chamber 11 that touches the inner surface of the upper shell 1, thereby improving the use effect.

[0074] The cooling assembly 8 includes a cooling jacket 801 , which is fixedly mounted on the outer surface of the upper shell 1 . A water delivery channel is provided in the cooling jacket 801 , and cooling water flows in the water delivery channel to cool the upper shell 1 .

[0075] The cooling jacket 801 is provided with a water inlet and a water outlet. The water inlet of the cooling jacket 801 is connected with a cooling water inlet pipe 802. The other end of the cooling water inlet pipe 802 is connected with a seawater source. A cooling water pump 803 is connected in series with the cooling water inlet pipe 802. The cooling water pump 803 is used to pump seawater from the seawater source and transport it to the cooling jacket 801 through the cooling water inlet pipe 802.

[0076] The water outlet of the cooling jacket 801 is connected to a cooling water return pipe 804 , and the other end of the cooling water return pipe 804 is connected to a seawater source. The seawater in the cooling jacket 801 is discharged through the cooling water return pipe 804 and flows back to the seawater source.

[0077] The present invention also provides a method for distilling seawater under negative pressure. Based on the above-mentioned device for distilling seawater under negative pressure, the method is carried out according to the following steps: Step 1, first open the second reversing valve 703 and the switch valve 706, and start the vacuum pump 707. The vacuum pump 707 is used to evacuate the second fresh water tank 701 and the distillation chamber 11. When the vacuum degree in the distillation chamber 11 reaches 1KPa-10KPa, turn on the flow switch 404 and the heater 405. The heater 405 is used to heat the seawater so that the inlet temperature of the seawater is 30°C-50°C. At this time, the seawater in the seawater source is sucked through the vacuum state in the distillation chamber 11, and the seawater is transported to the sprinkler head 6 through the water inlet pipe 401 and the metal universal pipe 402 and sprayed out.

[0078] Step 2, start the high-speed motor 504 of the centrifugal mist-making component 5. The high-speed motor 504 drives the centrifugal disk 505 to rotate at high speed through the rotating shaft 503. The high-temperature seawater sprayed by the water spray head 6 falls on the centrifugal disk 505. The centrifugal disk 505 rotates at high speed to break up the seawater, so that the seawater is rapidly atomized under the action of flash evaporation. At this time, liquid seawater drips into the water storage tank 3, and the atomized water vapor rises and flows toward the upper chamber of the distillation chamber 11. When the water vapor contacts the inner surface of the upper shell 1, the water vapor condenses into liquid water droplets on the inner surface of the upper shell 1. The liquid water droplets slide along the inner surface of the upper shell 1 under the action of gravity into the fresh water tank 201. At this time, the fresh water tank 201 is used to temporarily store the fresh water.

[0079] Step three, then close the switch valve 706, and switch the working state of the second reversing valve 703, so that the gas discharged during the vacuum pump 707 is transported to the condenser 704 through the second reversing valve 703. At this time, the condenser 704 is used to condense the moisture in the flowing gas to form fresh water and transport it to the second fresh water tank 701.

[0080] Step 4: The cooling water pump 803 of the cooling assembly 8 is used to suck seawater from the seawater source and transport it to the cooling jacket 801 through the cooling water inlet pipe 802; the seawater flowing in the cooling jacket 801 is used to cool the upper shell 1, thereby improving the condensation effect of the upper shell 1 on water vapor; the seawater in the cooling jacket 801 is discharged through the cooling return water pipe 804 and flows back to the seawater source.

[0081] Step 5: The first fresh water pump 1002 on the fresh water output pipeline 10 is used to pump the fresh water in the fresh water tank 201 and transport it to the first fresh water tank 1001. The first fresh water tank 1001 is used to temporarily store the fresh water.

[0082] Step 6: When the seawater in the water storage tank 3 reaches the highest liquid level, the concentrated brine return pump 901 on the concentrated brine return pipeline 9 is operated to pump the seawater in the water storage tank 3 and transport it to the concentrated brine tank 12.

[0083] Step 7, when the seawater refluxed in the concentrated brine tank 12 can still be used, the first reversing valve 403 is controlled to work so that the reflux pipeline 407 is connected to the water inlet pipe 401. At this time, the seawater in the concentrated brine tank 12 is transported to the water inlet pipe 401 through the reflux pipeline 407, and the heater 405 is used to heat the seawater so that the inlet temperature of the seawater is maintained at 30°C-50°C, and then the seawater is sprayed out through the sprinkler head 6.

[0084] Step 8: Then collect the fresh water obtained in the first fresh water tank 1001 and the second fresh water tank 701; start the second fresh water pump 1006 and the third fresh water pump 1009, the second fresh water pump 1006 works to suck the fresh water in the second fresh water tank 701 through the fresh water pipe 1003 and transport it to the normal pressure fresh water tank 1004, the third fresh water pump 1009 works to suck the fresh water in the first fresh water tank 1001 through the fresh water transport pipe 1007 and transport it to the normal pressure fresh water tank 1004, at this time the normal pressure fresh water tank 1004 is used to collect the produced fresh water.

[0085] Embodiment 2, as Figure 4 As shown, in this embodiment 2, the overall structure of the negative pressure distillation seawater device can also be Figure 4 As shown, the water inlet pipe 401 is located below the heater 405 and is also connected in series with a water inlet pump 408. The water inlet side of the water inlet pump 408 is connected in series with a series pipe 409. The other end of the series pipe 409 is connected to the cooling pipeline in the condenser 704. The water inlet end of the cooling pipeline in the condenser 704 is connected to the water inlet cooling pipe 709. The other end of the water inlet cooling pipe 709 is connected to the seawater source. The first reversing valve 403 is connected in series on the water inlet cooling pipe 709.

[0086] With such a design, the water inlet pump 408 is used to pump seawater from the seawater source. At this time, the seawater in the seawater source is transported to the cooling pipeline in the condenser 704 through the water inlet cooling pipe 709, and then transported to the water inlet pipe 401 through the series pipe 409 and the water inlet pump 408. At this time, the seawater flows through the cooling pipeline in the condenser 704 and exchanges heat with the water vapor flowing in the condenser 704, thereby condensing the water vapor and preliminarily heating the seawater at the same time, which is convenient for use.

[0087] The reflux pipeline 407 is arranged between the water inlet pump 408 and the water storage tank 3 , one end of the reflux pipeline 407 is connected to the drain outlet of the water storage tank 3 , and the other end of the reflux pipeline 407 is connected to the water inlet end of the water inlet pump 408 .

[0088] In this embodiment 2, the cooling component 8 can also be Figure 4As shown in the structure, the cooling assembly 8 includes a spray ring pipe 805 arranged on the outside of the upper shell 1 and close to its upper position, and a plurality of spray nozzles are arranged on one side of the spray ring pipe 805 close to the outer surface of the upper shell 1, and the water outlet end of the cooling water inlet pipe 802 is connected to the spray ring pipe 805.

[0089] A water collecting tank 806 is fixedly installed on the outer surface of the upper shell 1 near its lower position, and the water inlet end of the cooling water return pipe 804 is connected to the water collecting tank 806.

[0090] In this design, the cooling water pump 803 is used to suck the seawater in the seawater source and transport it to the spray ring pipe 805 through the cooling water inlet pipe 802. At this time, the seawater in the spray ring pipe 805 is sprayed onto the outer surface of the upper shell 1 through the spray nozzle to cool the upper shell 1. The spray water on the upper shell 1 is collected in the water collecting tank 806, and then flows back to the seawater source through the cooling return water pipe 804.

[0091] For those skilled in the art, according to the teachings of the present invention, without departing from the principles and spirit of the present invention, changes, modifications, substitutions and variations made to the implementation methods are still within the protection scope of the present invention.

Claims

1. A negative pressure seawater distillation device, comprising a lower housing (2), characterized in that: A water storage tank (3) is fixedly mounted below the lower shell (2); an upper shell (1) is sealedly mounted above the lower shell (2) via a sealing assembly; a distillation chamber (11) is arranged inside the upper shell (1) and the lower shell (2); a fresh water tank (201) is arranged on the inner surface of the lower shell (2) near the upper portion thereof; a centrifugal misting assembly (5) is arranged below the fresh water tank (201) in the distillation chamber (11); a water spray head (6) is arranged directly above the centrifugal misting assembly (5); a seawater delivery pipeline (4) for delivering seawater to the water spray head (6) is arranged on the outer side of the lower shell (2); and a vacuum extraction pipeline (7) is arranged above the upper shell (1).

2. A negative pressure seawater distillation device according to claim 1, characterized in that: The vacuum pumping pipeline (7) is used to evacuate the distillation chamber (11), and the vacuum degree in the distillation chamber (11) is (1) KPa-(10) KPa. The seawater delivery pipeline (4) is used to heat the external seawater and then deliver it to the water spray head (6) for spraying. The inlet temperature of the seawater is (30)°C-(50)°C.

3. A negative pressure seawater distillation device according to claim 2, characterized in that: The centrifugal mist-making component (5) comprises an elevated cylinder platform (501), the elevated cylinder platform (501) being coaxially and fixedly mounted on the inner bottom surface of the water storage tank (3), a support sleeve (502) being fixedly mounted above the elevated cylinder platform (501), and a rotating shaft (503) being coaxially mounted inside the supporting sleeve (502); the upper end of the rotating shaft (503) extending to the top of the supporting sleeve (502) and being fixedly mounted with a centrifugal disc (505), the lower end of the rotating shaft (503) penetrating the elevated cylinder platform (501) and being transmission-connected with a high-speed motor (504), and the high-speed motor (504) being fixedly mounted inside the elevated cylinder platform (501).

4. A negative pressure seawater distillation device according to claim 3, characterized in that: The cross section of the centrifugal disk (505) is an arc-shaped disk structure. The upper end surface of the centrifugal disk (505) is located below the upper edge surface of the fresh water tank (201). The centrifugal disk (505) rotates at a high speed to disperse the high-temperature seawater sprayed by the water spray head (6), so that the seawater is rapidly atomized under the action of flash evaporation. The high-temperature seawater dispersed by the centrifugal disk (505) is located below the fresh water tank (201) and will not be thrown into the fresh water tank (201).

5. A negative pressure seawater distillation device according to claim 4, characterized in that: The seawater delivery pipeline (4) comprises a metal universal tube (402), the metal universal tube (402) being fixedly mounted on the elevated cylinder platform (501), the upper end of the metal universal tube (402) being connected to the water spray head (6), the other end of the metal universal tube (402) being located inside the elevated cylinder platform (501) and being connected to a water inlet pipe (401), the other end of the water inlet pipe (401) being connected to a seawater source; a first reversing valve (403), a flow switch (404) and a heater (405) are sequentially connected in series on the water inlet pipe (401) along the flow direction of the seawater.

6. A negative pressure seawater distillation device according to claim 5, characterized in that: A concentrated salt water tank (12) is arranged outside the lower shell (2); a concentrated salt water return pipeline (9) is arranged between the concentrated salt water tank (12) and the water storage tank (3); a first non-return valve (902) and a concentrated salt water return pump (901) are sequentially connected in series on the concentrated salt water return pipeline (9) in the direction of coastal water flow; and a return pipeline (407) is arranged between the concentrated salt water tank (12) and the first reversing valve (403).

7. A negative pressure seawater distillation device according to claim 6, characterized in that: The lower shell (2) is connected to a fresh water output pipeline (10); one end of the fresh water output pipeline (10) passes through the outer surface of the lower shell (2) and is connected to the fresh water tank (201); the other end of the fresh water output pipeline (10) is connected to a first fresh water tank (1001); and a first fresh water pump (1002) is connected in series to the fresh water output pipeline (10).

8. The negative pressure seawater distillation device according to claim 7, characterized in that: One end of the vacuum pumping pipeline (7) passes through the upper shell (1) and is connected to the distillation chamber (11); the other end of the vacuum pumping pipeline (7) is connected to a second fresh water tank (701); a second check valve (702), a second reversing valve (703) and a condenser (704) are sequentially connected in series on the vacuum pumping pipeline (7) along the flow direction of air; the second reversing valve (703) is also connected to an exhaust pipe (705); the other end of the exhaust pipe (705) is connected to a switch valve (706); A vacuum pump (707) is connected in parallel between the second one-way valve (702) and the second reversing valve (703) on the vacuum extraction pipeline (7), and an air outlet of the vacuum pump (707) is connected to an exhaust pipe (705) between the second reversing valve (703) and the switch valve (706).

9. The negative pressure seawater distillation device according to claim 8, characterized in that: A cooling assembly (8) is installed on the outer surface of the upper shell (1), the cooling assembly (8) comprising a cooling jacket (801), the cooling jacket (801) being fixedly installed on the outer surface of the upper shell (1), the water inlet of the cooling jacket (801) being connected to a cooling water inlet pipe (802), the other end of the cooling water inlet pipe (802) being connected to a seawater source, the cooling water inlet pipe (802) being connected in series to a cooling water pump (803), and the water outlet of the cooling jacket (801) being connected to a cooling water return pipe (804).

10. A method for distilling seawater under negative pressure, based on the device for distilling seawater under negative pressure according to claim 9, characterized in that: The method proceeds as follows: Step 1: First, open the second reversing valve (703) and the switch valve (706), and start the vacuum pump (707) to evacuate the second fresh water tank (701) and the distillation chamber (11). When the vacuum degree in the distillation chamber (11) reaches (1) KPa-(10) KPa, turn on the flow switch (404) and the heater (405). The heater (405) is used to heat the seawater so that the inlet temperature of the seawater is (30)°C-(50)°C. At this time, the seawater in the seawater source is transported to the water spray head (6) through the water inlet pipe (401) and the metal universal pipe (402) and sprayed out. Step 2: starting the high-speed motor (504) of the centrifugal mist-making component (5) to drive the rotating shaft (503) to drive the centrifugal disc (505) to rotate at high speed, and the high-temperature seawater sprayed by the water spray head (6) falls on the centrifugal disc (505). The centrifugal disc (505) rotates at high speed to break up the seawater, so that the seawater is rapidly atomized under the action of flash evaporation. At this time, the liquid seawater drips into the water storage tank (3), and the atomized water vapor rises. When the water vapor contacts the inner surface of the upper shell (1), the water vapor condenses into liquid water droplets on the inner surface of the upper shell (1). The liquid water droplets slide along the inner surface of the upper shell (1) under the action of gravity into the fresh water tank (201); Step 3: Then close the switch valve (706) and switch the working state of the second reversing valve (703) so that the gas discharged during the vacuum pump (707) is transported to the condenser (704) through the second reversing valve (703). At this time, the condenser (704) is used to condense the moisture in the gas flowing through to form fresh water and transport it to the second fresh water tank (701); Step 4: The cooling water pump (803) of the cooling assembly (8) is used to pump seawater from the seawater source and transport it to the cooling jacket (801) through the cooling water inlet pipe (802); the seawater flowing in the cooling jacket (801) is used to cool the upper shell (1) to improve the condensation effect of the upper shell (1) on water vapor; the seawater in the cooling jacket (801) is discharged through the cooling water return pipe (804); Step 5: The first fresh water pump (1002) on the fresh water output pipeline (10) is used to pump the fresh water in the fresh water tank (201) and transport it to the first fresh water tank (1001); Step 6: When the seawater in the water storage tank (3) reaches the highest liquid level, the concentrated brine return pump (901) on the concentrated brine return pipeline (9) is operated to pump the seawater in the water storage tank (3) and transport it to the concentrated brine tank (12); Step 7: When the seawater refluxed from the concentrated brine tank (12) can still be used, the first reversing valve (403) is controlled to operate so that the reflux pipeline (407) is connected to the water inlet pipe (401). At this time, the seawater in the concentrated brine tank (12) is transported to the water inlet pipe (401) through the reflux pipeline (407), and the seawater is heated by the heater (405) and then sprayed out through the water spray head (6); Step 8: Then, the fresh water obtained in the first fresh water tank (1001) and the second fresh water tank (701) are collected.

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