An air-sweeping seawater desalination membrane distiller

Abstract

The invention discloses an air-sweeping seawater desalination membrane distiller, comprising: a central tube and a shell, and also comprising an evaporator assembly arranged in the shell for cooling hot seawater; the central tube is arranged in the middle of the shell, arranged along the axis of the shell, and both ends are respectively passed through the shell, and the tube wall of the central tube located inside the shell is made of a semi-permeable membrane; a plurality of fresh water outlets are arranged at the bottom of the shell, and a circulating air inlet, a circulating air outlet, a refrigerant inlet and a refrigerant outlet are respectively arranged on the side wall, and the refrigerant inlet and the refrigerant outlet are respectively connected to the evaporator assembly; the device has a compact structure, saves occupied space, can appropriately increase the blowing wind speed under the condition of the same energy consumption, increase the water vapor flux and the heat exchange efficiency of the evaporator assembly, make the water vapor condense faster, and improve the water production rate of the whole device.

Description

Technical Field

[0001] The invention relates to the technical field of air-sweeping membrane distillation equipment, in particular to an air-sweeping seawater desalination membrane distiller. Background Art

[0002] The structure of the existing gas-sweeping membrane distillation device is as follows: Figure 4 As shown, the membrane distillation device is divided into a hot end a2 and a cold end a3 by a semipermeable membrane a1. The bottom of the cold end is connected to a blower a4, and the top is connected to an evaporator a5 through a pipeline. The evaporator is connected to a fresh water tank a6 through a pipeline, and is provided with an inlet a7 and an outlet a8 for a condensing agent. Hot seawater enters the hot end of the membrane distillation device through a pipeline, and enters the cold end through the semipermeable membrane used for distillation. The blower continuously blows dry gas into the cold end, blowing the water vapor that has passed through the semipermeable membrane into the evaporator for cooling and condensation, and then the condensed fresh water is collected in the fresh water tank.

[0003] The above device has the defects of too long pipelines, complex equipment and high operating costs.

[0004] It can be seen that the existing technology still needs to be improved and enhanced. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide an air-swept seawater desalination membrane distiller, aiming to solve at least one of the above-mentioned problems of the air-swept membrane distiller in the prior art.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] An air-sweeping seawater desalination membrane distiller comprises: a central tube and a shell, and also comprises an evaporator assembly arranged in the shell for cooling hot seawater; the central tube is arranged in the middle of the shell, arranged along the axis of the shell, and the two ends respectively pass through the shell, and the tube wall of the central tube located inside the shell is made of a semi-permeable membrane; a plurality of fresh water outlets are arranged at the bottom of the shell, and a circulating air inlet, a circulating air outlet, a refrigerant inlet and a refrigerant outlet are respectively arranged on the side wall, and the refrigerant inlet and the refrigerant outlet are respectively connected to the evaporator assembly.

[0008] In the air-swept seawater desalination membrane distiller, the evaporator assembly includes a header fixing seat, an upper header, a lower header and a plurality of heat exchange tubes; the header fixing seats are respectively arranged at the upper and lower parts of the shell, and are used to fix the upper header and the lower header, the upper header and the lower header are respectively arranged along the circumference of the central tube, and each heat exchange tube is arranged along the axial direction of the central tube, and the two ends are respectively connected to the upper header and the lower header.

[0009] In the air-swept seawater desalination membrane distiller, the heat exchange tubes are arranged at equal intervals and circumferentially on the outside of the central tube.

[0010] In the air-sweeping seawater desalination membrane distiller, the refrigerant inlet is arranged at the lower part of the shell and communicates with the lower header, and the refrigerant outlet is arranged at the upper part of the shell and communicates with the upper header.

[0011] In the air-sweeping seawater desalination membrane distiller, the circulating air inlet is arranged at the lower part of the shell, and the circulating air outlet is arranged at the upper part of the shell.

[0012] In the air-sweeping seawater desalination membrane distiller, the circulating air inlet and the circulating air outlet are arranged between the upper header and the lower header.

[0013] In the air-sweeping seawater desalination membrane distiller, two fresh water outlets are provided, which are respectively arranged on both sides of the radial direction of the lower end of the central tube.

[0014] In the air-sweeping seawater desalination membrane distiller, the distiller further comprises an upper end cap and a lower end cap respectively arranged at the upper end and the lower end of the central tube.

[0015] Beneficial effects:

[0016] The present invention provides an air-sweeping seawater desalination membrane distiller, which integrates an evaporator assembly between a central tube for separating hot seawater and a shell, so that the structure of the device is more compact, the composition of the device is simplified, the floor space of the device is saved, and a plurality of tanks can be assembled in parallel for use as required, so that operation and maintenance are convenient; the length of the pipeline is shortened, the energy consumption is reduced, and the blowing wind speed can be appropriately increased under the condition of the same energy consumption, so that the water vapor flux and the heat exchange efficiency of the evaporator assembly are increased, so that the water vapor condenses faster, and the water production rate of the entire device is improved; the structure is also convenient for the recycling of dry air, so as to save costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a side view of the air-swept seawater desalination membrane distiller provided by the present invention.

[0018] Figure 2 It is a front view of the air-sweeping seawater desalination membrane distiller.

[0019] Figure 3 It is a front cross-sectional view of the main view of the air-swept seawater desalination membrane distiller.

[0020] Figure 4 It is a schematic diagram of the structure of a common gas-sweeping membrane distillation device in the prior art. DETAILED DESCRIPTION

[0021] The present invention provides an air-sweeping seawater desalination membrane distiller. In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] See also Figure 1-3 The present invention provides an air-sweeping seawater desalination membrane distiller, comprising: a central tube 1 and a shell 2, and also comprising an evaporator 3 component arranged in the shell 2 for cooling hot seawater; the central tube 1 is arranged in the middle of the shell 2, arranged along the axis of the shell 2, and the two ends respectively pass through the shell 2, and the tube wall of the central tube 1 located inside the shell 2 is made of a semi-permeable membrane A; a plurality of fresh water outlets 21 are arranged at the bottom of the shell 2, and a circulating air inlet 22, a circulating air outlet 23, a refrigerant inlet 24 and a refrigerant outlet 25 are respectively arranged on the side wall, and the refrigerant inlet 24 and the refrigerant outlet 25 are respectively connected to the evaporator component 3.

[0023] In actual applications, hot seawater enters the distiller from the upper port of the central tube, and water vapor enters the shell through the semipermeable membrane on the wall of the central tube. The shell serves as the cold end of the entire distiller and is used to cool the hot seawater that passes through the semipermeable membrane, causing it to condense and flow out from the fresh seawater outlet at the bottom of the shell and be collected in the fresh water tank. The evaporator assembly in the shell is used to enhance the cooling effect of the shell and accelerate the condensation efficiency of the hot seawater. The distiller integrates the evaporator assembly into the shell, making the structure of the equipment more compact, simplifying the composition of the equipment, shortening the delivery pipeline, reducing energy consumption, and improving the water production efficiency; and multiple distiller can be connected through pipelines as needed. The distiller heats the seawater through the air conditioning system and controls the evaporator assembly to cool and condense the water vapor at the cold end to complete the desalination of the entire seawater.

[0024] The evaporator assembly 3 includes a header fixing seat 31, an upper header 32, a lower header 33 and a plurality of heat exchange tubes 34; the header fixing seat 31 is respectively arranged at the upper and lower parts of the shell 2, and is used to fix the upper header 32 and the lower header 33. In this embodiment, the header fixing seat includes 4 or 6 pieces, and is symmetrically arranged up and down, while ensuring that the upper header and the lower header are fixed, the outflow of the cooled fresh water in the shell is reduced; the upper header 32 and the lower header 33 are respectively arranged along the circumference of the central tube 1, and each heat exchange tube 34 is arranged along the axial direction of the central tube 1, and the two ends are respectively connected to the upper header 32 and the lower header 33.

[0025] In actual application, the coolant flows from the lower header into the evaporator assembly, then into each heat exchange tube, and then merges into the upper header for discharge. The heat exchange tube and the central tube are arranged in the same direction, which can balance the cooling effect of the upper and lower shells and enhance the cooling effect. Preferably, fins are provided on the outer wall of the heat exchange tube to accelerate the condensation of water vapor. In this embodiment, the coolant is water, which can be recycled.

[0026] Furthermore, the heat exchange tubes 34 are arranged at equal intervals and are arranged circumferentially on the outside of the central tube 1. To balance the cooling effect of the outer circumference of the central tube, the heat exchange tubes can be arranged in number and spacing according to the actual heat exchange effect. When the heat exchange tubes are arranged in multiple layers, correspondingly, multiple upper headers and lower headers connected thereto should also be arranged. The two ends of each layer of heat exchange tubes are respectively connected to an upper header and a lower header. Each upper header is connected to each other, and the upper header located in the outermost layer is connected to the coolant outlet; each lower header is also connected to each other, and the lower header located in the outermost layer is connected to the coolant inlet. If the heat exchange tubes are arranged in multiple layers (one circumference is one layer), the heat exchange tubes in two adjacent layers are staggered to improve the heat exchange effect.

[0027] The refrigerant inlet 24 is arranged at the lower part of the shell 2 and is connected to the lower header 33. The refrigerant outlet 25 is arranged at the upper part of the shell 2 and is connected to the upper header 32. The flow directions of the coolant and the water vapor after condensation in the shell are opposite to each other, thereby improving the heat exchange effect of the coolant. Generally, the refrigerant inlet and the refrigerant outlet are staggered and respectively arranged at the radial ends of the shell, thereby extending the residence time of the refrigerant in the shell and improving its heat exchange effect.

[0028] The circulating air inlet 22 is arranged at the lower part of the housing 2, and the circulating air outlet 23 is arranged at the upper part of the housing 2. Generally, the circulating air inlet and the circulating air outlet are staggered and arranged at both ends of the housing in the radial direction, respectively, to extend the residence time of the circulating air in the housing and improve its utilization rate.

[0029] The circulating air inlet 22 and the circulating air outlet 23 are arranged between the upper header 32 and the lower header 33, so that the blown-in dry air is within the cooling range of the evaporator assembly; in this embodiment, the circulating air inlet and the coolant inlet are respectively arranged at the radial ends of the shell to enhance the cooling effect.

[0030] There are two desalinated seawater outlets 21, which are respectively arranged on both sides of the radial direction of the lower end of the central tube 1, so that the desalinated seawater after condensation on both sides of the central tube can be quickly discharged.

[0031] The distiller also includes an upper head 4 and a lower head 5 respectively arranged at the upper and lower ends of the shell 2. In this embodiment, the upper head and the lower head are hemispherical, with the arc surface facing outward, and are seamlessly connected to the shell and the upper and lower ends of the central tube respectively, to prevent the fresh seawater in the shell from escaping. The two ends of the central tube pass through the upper head and the lower head respectively, the upper end thereof serves as the inlet of hot seawater, and the lower end is used as the outlet of hot seawater. Specifically, a flow control valve is provided at the lower end of the central tube to control the flow rate of the hot seawater flowing out of the central tube to be constant, thereby stabilizing the conversion rate of seawater and the water production rate of the equipment.

[0032] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the protection scope of the claims attached to the present invention.

Claims

1. An air-sweeping seawater desalination membrane distiller, characterized in that: include: The central tube and the shell also include an evaporator assembly arranged in the shell for cooling hot seawater; the central tube is arranged in the middle of the shell, arranged along the axis of the shell, and the two ends are respectively passed through the shell, and the tube wall of the central tube located inside the shell is made of a semi-permeable membrane; a plurality of fresh seawater outlets are arranged at the bottom of the shell, and a circulating air inlet, a circulating air outlet, a refrigerant inlet and a refrigerant outlet are respectively arranged on the side wall, and the refrigerant inlet and the refrigerant outlet are respectively connected to the evaporator assembly; the evaporator assembly includes a plurality of header fixing seats, an upper header, a lower header and a plurality of heat exchange tubes; the header fixing seats are respectively arranged at the upper and lower parts of the shell, and are used to fix the upper header and the lower header, and the upper header The heat exchange tubes and the lower header are respectively arranged along the circumference of the central tube, each heat exchange tube is parallel to the axis of the central tube, and the two ends are respectively connected with the upper header and the lower header; fins are provided on the outer wall of the heat exchange tube, and the heat exchange tube is arranged in multiple layers. The two adjacent layers of heat exchange tubes are staggered, and the heat exchange tubes of each layer are arranged equidistantly and circumferentially on the outside of the central tube. The two ends of the heat exchange tubes of each layer are respectively connected to an upper header and a lower header, each upper header is connected, the upper header located at the outermost layer is connected to the refrigerant outlet, each lower header is also connected, and the lower header located at the outermost layer is connected to the refrigerant inlet; the circulating air inlet is arranged at the lower part of the shell, and the circulating air outlet is arranged at the upper part of the shell.

2. The air-sweeping seawater desalination membrane distiller according to claim 1, characterized in that: The refrigerant inlet is arranged at the lower part of the shell and communicates with the lower header, and the refrigerant outlet is arranged at the upper part of the shell and communicates with the upper header.

3. The air-sweeping seawater desalination membrane distiller according to claim 1, characterized in that: The circulating air inlet and the circulating air outlet are arranged between the upper header and the lower header.

4. The air-sweeping seawater desalination membrane distiller according to claim 1, characterized in that: There are two fresh water outlets, which are respectively arranged on both sides of the radial direction of the lower end of the central pipe.

5. The air-sweeping seawater desalination membrane distiller according to claim 1, characterized in that: The distiller also includes an upper head and a lower head which are respectively arranged at the upper end and the lower end of the central tube.

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