Three-fluid four-tube-pass shell-and-tube heat exchanger

Abstract

The three-fluid four-tube-pass shell-and-tube heat exchanger comprises an outer shell, and heat exchange tubes are jointly installed on end plates at the two ends of the outer shell in a penetrating mode. A front cover shell and a rear cover shell are installed at the two ends of the outer shell, the portion between the front cover shell and an end plate is divided into two upper small spaces and a lower large space through a pass dividing plate, and a refrigerant inlet and a circulating water inlet are formed right opposite to the small spaces respectively. The space between the rear housing and the end plate is divided into two small spaces which are arranged up and down on one side and a large space on the other side by a pass dividing plate, and a refrigerant outlet and a circulating water outlet are respectively formed right opposite to the small spaces; the circulating water inlet and the circulating water outlet directly face front and back and are communicated with two ends of the same heat exchange tube; a refrigerant enters the small space of the front cover shell from the refrigerant inlet, flows to the large space of the rear cover shell through the heat exchange pipe, then turns back to flow to the large space of the front cover shell through the heat exchange pipe and finally flows out of the refrigerant outlet of the rear cover shell, and a four-tube-pass heat exchange structure is formed in combination with flowing from the circulating water inlet to the circulating water outlet. The heat exchange system is greatly simplified, the occupied area is reduced, and the heat exchange effect is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of shell and tube heat exchangers, in particular to a three-fluid four-pass shell and tube heat exchanger. Background Art

[0002] Low-temperature crystallization skid-mounted equipment utilizing a heat pump system meets the market's urgent need for efficient, energy-saving, and convenient wastewater treatment equipment. In low-temperature heat pump crystallization equipment, the cooling of secondary steam typically requires heat exchange with the refrigerant in a dry evaporator and then with circulating water in an auxiliary cooler to ensure complete cooling.

[0003] like Figure 1 As shown, in the existing secondary steam cooling in the separator 100, the heat exchanger usually adopts a shell and tube heat exchanger with two fluids, including a main heat exchanger 300 for heat exchange between refrigerant and steam, and an auxiliary heat exchanger 200 for heat exchange between circulating water and steam; the secondary steam comes out from the steam outlet 101 of the separator 100, enters the main heat exchanger 300 for heat exchange and cooling, and then the condensed water flows out from the corresponding main outlet 400. The main heat exchanger 300 is equipped with a refrigerant inlet and outlet 301 for the inlet and outlet flow of the refrigerant; when necessary, the valve connecting the separator 100 to the auxiliary heat exchanger 200 is opened, and the secondary steam flowing out from the steam outlet 101 of the separator 100 enters the auxiliary heat exchanger 200 for heat exchange and cooling, and then the condensed water flows out from the corresponding main outlet 400. The auxiliary heat exchanger 200 is equipped with a circulating water inlet and outlet 201 for the inlet and outlet flow of circulating water.

[0004] The existing cooling methods have the following problems:

[0005] Complex equipment: Multiple heat exchangers need to be connected in series, which increases the complexity of the equipment and the floor space required;

[0006] Energy loss: When switching between multiple heat exchangers to transfer heat, energy is lost, reducing the overall efficiency of the system. Summary of the Invention

[0007] To solve the above problems, the present application provides a three-fluid four-pass shell and tube heat exchanger with a rational structure, thereby greatly simplifying the heat exchange system, reducing the floor space, and ensuring the heat exchange effect.

[0008] The technical solutions adopted in the present invention are as follows:

[0009] A three-fluid four-pass shell and tube heat exchanger comprises an outer shell of a cylindrical structure, end plates are respectively installed at both ends of the outer shell, and a plurality of heat exchange tubes are installed between the end plates at both ends; a front cover shell and a rear cover shell are respectively installed at both ends of the outer shell, the space between the front cover shell and the corresponding end plates is divided into two small spaces above and a large space below by a dividing plate, and a refrigerant inlet and a circulating water inlet are respectively installed on the front cover shell opposite the two small spaces; the space between the rear cover shell and the corresponding end plates is divided into two small spaces arranged up and down on one side and a large space on the other side by a dividing plate, and a refrigerant outlet and a circulating water outlet are respectively installed on the rear cover shell opposite the two small spaces; the small spaces corresponding to the circulating water inlet and the circulating water outlet are opposite to and connected to the two ends of the same heat exchange tube.

[0010] As a further improvement of the above technical solution:

[0011] The splitter plate includes a long plate along the chord direction of the end plate and a short plate extending from the long plate toward the edge of the end plate; the long plate of the splitter plate located between the front cover and the corresponding end plate is arranged horizontally, and the long plate of the splitter plate located between the rear cover and the corresponding end plate is arranged vertically.

[0012] The range dividing plate is in a T-shaped structure, and the intersection of the long plate and the short plate of the range dividing plate is directly opposite to the center of the end plate.

[0013] The heat exchange tubes are evenly divided into four areas along the plane direction of the end plate according to four quadrants. The small space corresponds to the heat exchange tubes in a single area, and the large space corresponds to the heat exchange tubes in two adjacent areas.

[0014] It also includes a steam inlet and a condensed water outlet installed on the circumferential wall of the outer shell. The steam inlet is arranged close to the refrigerant outlet and the circulating water outlet, and the condensed water outlet is arranged close to the refrigerant inlet and the circulating water inlet.

[0015] A plurality of baffles are installed at intervals along the axial direction inside the outer shell between the steam inlet and the condensed water outlet, and staggered channels are formed between the edges of adjacent baffles and the inner wall of the outer shell.

[0016] The deflector is an arched structure arranged along the cross-section of the outer shell and fitted with an arc edge, and a channel is formed between the chord of the arched structure and the inner wall of the outer shell.

[0017] The top and bottom ends of the baffle are respectively concave to form V-shaped grooves.

[0018] A plurality of support rods are installed together on the plurality of baffles, and the ends of the support rods are installed on the end plates.

[0019] The edges of the front cover shell and the rear cover shell are respectively extended to form flanges that fit with the corresponding end plates, and the side surfaces of the end plates are provided with limiting grooves for the front cover shell and the rear cover shell to fit; the bottom surface of the outer shell is provided with support legs at intervals along the axial direction.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] When the present invention is used, the refrigerant enters the small space of the front housing from the refrigerant inlet, flows to the large space of the rear housing through the heat exchange tube, then returns and flows to the large space of the front housing through the heat exchange tube, and finally flows out from the refrigerant outlet of the rear housing. Combined with the flow from the circulating water inlet to the outlet, a four-pipe-pass heat exchange structure is formed, which greatly simplifies the heat exchange system, reduces the floor space, and ensures the heat exchange effect.

[0022] The present invention also includes the following advantages:

[0023] Integrating the heat exchange process of refrigerant, circulating water and steam into one shell ensures heat exchange efficiency while effectively reducing the number of heat exchangers and improving overall utilization efficiency.

[0024] The combination of the splitter plate and the heat exchange tubes strictly isolates the refrigerant and circulating water, allowing them to flow independently in the heat exchanger and efficiently exchange heat with the steam inside the outer shell. This effectively optimizes the overall thermal performance of the heat exchanger, improves and ensures heat exchange efficiency, and avoids cross contamination between fluids. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the layout diagram of the existing cooling equipment used for the secondary steam of the separator.

[0026] Figure 2 This is a layout diagram of the separator secondary steam cooling using a three-fluid four-pass shell and tube heat exchanger.

[0027] Figure 3 This is the external structural diagram of the three-fluid four-pass shell and tube heat exchanger of the present invention.

[0028] Figure 4 This is a structural diagram of the three-fluid four-pass shell and tube heat exchanger of the present invention (the front and rear covers are omitted).

[0029] Figure 5 for Figure 4 Schematic diagram from another perspective.

[0030] Figure 6 This is a schematic diagram of the layout of heat exchange tubes and baffles between the two end plates of the present invention.

[0031] Figure 7 Schematic diagram of the layout of the baffles of the present invention.

[0032] Among them: 100, separator; 101, steam outlet; 200, auxiliary heat exchanger; 201, circulating water inlet and outlet; 300, main heat exchanger; 301, refrigerant inlet and outlet; 400, main outlet; 500, three-fluid heat exchanger;

[0033] 1. Outer shell; 21. Steam inlet; 22. Condensate outlet; 3. Front cover; 41. Refrigerant inlet; 42. Refrigerant outlet; 51. Circulating water inlet; 52. Circulating water outlet; 6. Support legs; 7. Rear cover; 8. Range plate; 9. End plate; 10. Baffle; 11. Support rod;

[0034] 71. Limiting slot;

[0035] 90. Heat exchange tube;

[0036] 1001. Groove. DETAILED DESCRIPTION

[0037] The specific embodiments of the present invention will be described below with reference to the accompanying drawings.

[0038] like Figure 2 As shown, the steam outlet 101 of the separator 100 is connected to the three-fluid heat exchanger 500. By using the three-fluid heat exchanger 500, the connection and use of the existing two sets of shell and tube heat exchangers are replaced, which effectively simplifies the cooling system structure of the cooling separator 100 and reduces the floor space.

[0039] like Figure 3 、 Figure 4 and Figure 5 As shown, a three-fluid four-pass shell and tube heat exchanger of the present embodiment includes an outer shell 1 of a cylindrical structure, with end plates 9 respectively installed at both ends of the outer shell 1, and a plurality of heat exchange tubes 90 are installed between the end plates 9 at both ends; a front cover 3 and a rear cover 7 are respectively installed at both ends of the outer shell 1, and the space between the front cover 3 and the corresponding end plate 9 is divided into two small spaces above and a large space below by a dividing plate 8, and a refrigerant inlet 41 and a circulating water inlet 51 are respectively installed on the front cover 3 opposite to the two small spaces; the space between the rear cover 7 and the corresponding end plate 9 is divided into two small spaces arranged up and down on one side and a large space on the other side by the dividing plate 8, and a refrigerant outlet 42 and a circulating water outlet 52 are respectively installed on the rear cover 7 opposite the two small spaces; the small spaces corresponding to the circulating water inlet 51 and the circulating water outlet 52 are opposite to and connected to the two ends of the same heat exchange tube 90.

[0040] In this embodiment, when in use, the refrigerant enters the corresponding small space in the front cover shell 3 from the refrigerant inlet 41, flows to the large space in the rear cover shell 7 through the corresponding heat exchange tube 90, then returns and flows to the large space in the front cover shell 3 through the heat exchange tube 90, and finally flows out from the refrigerant outlet 42 of the rear cover shell 7. Combined with the flow of circulating water from the circulating water inlet 51 to the circulating water outlet 52, a four-pass heat exchange structure is formed.

[0041] In this embodiment, the partition plate 8 is combined with the heat exchange tube 90 to strictly isolate the refrigerant and the circulating water, and each of them flows independently and fully in the heat exchanger, and efficiently exchanges heat with the steam inside the outer shell 1, thereby realizing heat exchange between the three fluids in the same shell, effectively optimizing the overall thermal performance of the heat exchanger, improving and ensuring the heat exchange efficiency, and avoiding cross contamination between the fluids.

[0042] In actual use, the steam in the outer shell 1 can be cooled by heat exchange through refrigerant or circulating water, either alone or in combination.

[0043] The separator plate 8 includes a long plate along the chord direction of the end plate 9 and a short plate extending from the long plate toward the edge of the end plate 9; the long plate of the separator plate 8 located between the front cover shell 3 and the corresponding end plate 9 is arranged horizontally, and the long plate of the separator plate 8 located between the rear cover shell 7 and the corresponding end plate 9 is arranged vertically, so that the large space in the front cover shell 3 and the large space in the rear cover shell 7 are arranged horizontally and vertically respectively, and combined with the corresponding heat exchange tubes 90, a communicating flow channel space for the flow of refrigerant is formed, which effectively realizes and ensures the circulation and return flow of the refrigerant between the front cover shell 3 and the rear cover shell 7.

[0044] At the same time, through the arrangement of the front and rear dividing plates 8, corresponding small spaces are formed in the front and rear, which are connected through the corresponding heat exchange pipes 90 to form a flow channel space for the circulation water.

[0045] The dividing plate 8 is in a T-shaped structure, and the intersection of the long plate and the short plate of the dividing plate 8 is exactly opposite to the center of the end plate 9.

[0046] In this embodiment, the T-shaped partition plate 8 composed of long plates and short plates can conveniently and quickly divide the inner space of the front cover 3 and the rear cover 7 into two corresponding small spaces and one large space.

[0047] In this embodiment, the edge of the dividing plate 8 is in contact with the end plate 9 and the corresponding front cover 3 or rear cover 7 to achieve mutual isolation between the divided spaces.

[0048] The heat exchange tubes 90 are evenly divided into four areas along the plane direction of the end plate 9 according to the four quadrants. The small space corresponds to the heat exchange tubes 90 in a single area, and the large space corresponds to the heat exchange tubes 90 in two adjacent areas; it helps to ensure the stability of the fluid flow in each pipe pass, especially to ensure the smooth, smooth and stable return circulation of the refrigerant in the three pipe passes.

[0049] It also includes a steam inlet 21 and a condensed water outlet 22 installed on the circumferential wall of the outer shell 1. The steam inlet 21 is arranged close to the refrigerant outlet 42 and the circulating water outlet 52, and the condensed water outlet 22 is arranged close to the refrigerant inlet 41 and the circulating water inlet 51, thereby forming countercurrent heat exchange, effectively ensuring that steam heat exchange forms condensed water and flows out from the condensed water outlet 22.

[0050] like Figure 6 and Figure 7 As shown, a plurality of baffles 10 are installed at axial intervals inside the outer shell 1 between the steam inlet 21 and the condensate outlet 22, and staggered channels are formed between the edges of adjacent baffles 10 and the inner wall of the outer shell 1, thereby effectively improving and ensuring sufficient heat exchange of steam during flow, and helping to enhance the heat exchange effect between secondary steam and refrigerant and circulating water.

[0051] In this embodiment, the baffle 10 is provided with a plurality of holes for the heat exchange tubes 90 to pass through.

[0052] The baffle 10 is an arched structure arranged along the cross-sectional direction of the outer shell 1 and fitted with an arc edge. A channel is formed between the chord of the arched structure and the inner wall surface of the outer shell 1; thus, an S-shaped circulation channel is formed between the baffle 10 arranged staggered by the chord and the inner wall surface of the outer shell 1.

[0053] In this embodiment, the cross section of the channel between the chord of the bow structure and the outer shell 1 is smaller than the area of the baffle 10 , thereby promoting the flow of steam from the steam inlet 21 to the condensate outlet 22 .

[0054] The top and bottom ends of the baffle 10 are respectively concave to form a V-shaped groove 1001, which promotes the flow of steam and enables the condensed water to flow toward the condensed water outlet 22 and out.

[0055] The multiple baffles 10 are commonly installed with multiple support rods 11, and the ends of the support rods 11 are installed on the end plates 9, so that the baffles 10 are installed in the outer shell 1 and the structural reliability is guaranteed.

[0056] The edges of the front cover shell 3 and the rear cover shell 7 are respectively extended to form flanges that fit with the corresponding end plates 9. The side of the end plate 9 is provided with a limiting groove 71 for the front cover shell 3 and the rear cover shell 7 to ensure the reliability of the installation structure; the bottom surface of the outer shell 1 is equipped with support legs 6 along the axial interval.

[0057] In this embodiment, the heat exchange process of the refrigerant, circulating water and steam is integrated into one shell, which ensures the heat exchange efficiency while effectively reducing the number of heat exchangers and improving the overall utilization efficiency.

[0058] The use of the present invention is as follows:

[0059] Secondary steam enters the outer shell 1 of the three-fluid heat exchanger 500 from above through the steam inlet 21, and flows in the outer shell 1 due to the guidance of the baffle 10. The steam exchanges heat with the refrigerant in the heat exchange tube 90 inside the outer shell 1. The secondary steam releases heat to form condensed water and flows out from the condensed water outlet 22 at the lower part of the outer shell 1, and the refrigerant absorbs heat; when the refrigerant inlet pressure rises to the set value, the butterfly valve corresponding to the circulating water inlet 51 automatically opens, so that the secondary steam inside the outer shell 1 can exchange heat with the refrigerant and circulating water in the corresponding heat exchange tube 90 respectively, and the circulating water absorbs part of the heat of the secondary steam, thereby effectively helping to reduce the evaporation temperature of the heat pump system and ensure stable operation of the system.

[0060] In actual use, the refrigerant enters the corresponding small space from the refrigerant inlet 41 on the front cover shell 3, flows to the large space of the rear cover shell 7 through the corresponding heat exchange tube 90, and turns back through the heat exchange tube 90 to flow back to the large space of the front cover shell 3, and then turns back again through the heat exchange tube 90 to flow to the corresponding small space in the rear cover shell 7, and flows out from the refrigerant outlet 42, realizing the three-pass return flow of the refrigerant inside the outer shell 1.

[0061] In actual use, circulating water enters the corresponding small space from the circulating water inlet 51 on the front housing 3 , flows to the corresponding small space of the rear housing 7 through the corresponding heat exchange pipe 90 , and flows out from the circulating water outlet 52 .

[0062] The present invention realizes three-fluid four-pipe heat exchange, greatly simplifies the heat exchange system, reduces the floor space, and ensures the heat exchange effect.

[0063] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0064] The above description is an explanation of the present invention, not a limitation of the present invention. The scope of the present invention is defined in the claims. Any modifications may be made within the scope of protection of the present invention.

Claims

1. A three-fluid four-pass shell and tube heat exchanger, comprising an outer shell (1) of a cylindrical structure, characterized in that: End plates (9) are respectively installed at both ends of the outer shell (1), and a plurality of heat exchange tubes (90) are installed between the end plates (9); a front cover (3) and a rear cover (7) are respectively installed at both ends of the outer shell (1), and the space between the front cover (3) and the corresponding end plate (9) is divided into two small spaces at the top and a large space at the bottom by a partition plate (8), and a refrigerant inlet (41) and a circulating water inlet (51) are respectively installed on the front cover (3) facing the two small spaces; the space between the rear cover (7) and the corresponding end plate (9) is divided into two small spaces arranged up and down on one side and a large space on the other side by a partition plate (8), and a refrigerant outlet (42) and a circulating water outlet (52) are respectively installed on the rear cover (7) facing the two small spaces; the small spaces corresponding to the circulating water inlet (51) and the circulating water outlet (52) are respectively opposite to and connected to the two ends of the same heat exchange tube (90).

2. The three-fluid four-pass shell and tube heat exchanger according to claim 1, characterized in that: The split plate (8) includes a long plate along the chord direction of the end plate (9) and a short plate extending from the long plate toward the edge of the end plate (9); the long plate of the split plate (8) located between the front cover (3) and the corresponding end plate (9) is arranged horizontally, and the long plate of the split plate (8) located between the rear cover (7) and the corresponding end plate (9) is arranged vertically.

3. The three-fluid four-pass shell and tube heat exchanger according to claim 2, characterized in that: The dividing plate (8) is in a T-shaped structure, and the intersection of the long plate and the short plate of the dividing plate (8) is exactly opposite to the center of the end plate (9).

4. The three-fluid four-pass shell and tube heat exchanger according to claim 1, characterized in that: The heat exchange tubes (90) are evenly divided into four areas along the plane direction of the end plate (9) according to four quadrants, the small space corresponds to the heat exchange tubes (90) in a single area, and the large space corresponds to the heat exchange tubes (90) in two adjacent areas.

5. The three-fluid four-pass shell and tube heat exchanger according to claim 1, characterized in that: It also includes a steam inlet (21) and a condensed water outlet (22) installed on the circumferential wall of the outer shell (1), the steam inlet (21) is arranged close to the refrigerant outlet (42) and the circulating water outlet (52), and the condensed water outlet (22) is arranged close to the refrigerant inlet (41) and the circulating water inlet (51).

6. A three-fluid four-pass shell and tube heat exchanger according to claim 5, characterized in that: A plurality of baffles (10) are installed at intervals along the axial direction inside the outer shell (1) between the steam inlet (21) and the condensed water outlet (22), and staggered channels are formed between the edges of adjacent baffles (10) and the inner wall surface of the outer shell (1).

7. The three-fluid four-pass shell and tube heat exchanger according to claim 6, characterized in that: The baffle (10) is an arched structure arranged along the cross-sectional direction of the outer shell (1) and fitted with an arcuate edge, and a channel is formed between the chord of the arched structure and the inner wall surface of the outer shell (1).

8. The three-fluid four-pass shell and tube heat exchanger according to claim 6, characterized in that: The top and bottom ends of the baffle (10) are respectively concave to form grooves (1001) with a V-shaped structure.

9. The three-fluid four-pass shell and tube heat exchanger according to claim 6, characterized in that: A plurality of baffles (10) are commonly mounted with a plurality of support rods (11), and ends of the support rods (11) are mounted on the end plates (9).

10. The three-fluid four-pass shell and tube heat exchanger according to claim 1, characterized in that: The edges of the front cover (3) and the rear cover (7) are extended to form flanges that fit with the corresponding end plates (9), and the side surfaces of the end plates (9) are provided with limiting grooves (71) for fitting the front cover (3) and the rear cover (7); and the bottom surface of the outer shell (1) is provided with supporting legs (6) at intervals along the axial direction.

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