Secondary heat exchange device based on MVR evaporation system

Abstract

The utility model relates to the technical field of evaporation system heat exchange equipment, and discloses a secondary heat exchange device based on an MVR evaporation system. The secondary heat exchange device applied to the MVR evaporation system comprises a primary heat exchanger, a secondary heat exchanger A, a secondary heat exchanger B and switch valves arranged in front of and behind the heat exchangers. The two-stage heat exchanger solves the problems that a flow channel is narrow due to the compact structure of a heat exchanger, separated solids are gradually increased after long-time work, a plate heat exchanger is blocked, and a system is shut down in a severe case, and the two-stage heat exchanger can operate more stably and is smaller in blocking probability in the field of wastewater treatment; according to the two-stage heat exchanger, more equipment investment is saved, replacement of quick-wear parts is reduced, when blockage occurs, the number of heat exchange plates needing to be cleaned is smaller, and blockage clearing is faster. The heat exchanger is compact in structure and more in flow channels, the plate heat exchanger cannot be blocked or cause system shutdown after long-time work, and operation is more stable.

Description

Technical Field

[0001] The utility model relates to the technical field of heat exchange equipment for evaporation systems, in particular to a two-stage heat exchange device based on an MVR evaporation system. Background Art

[0002] The heat exchanger is used for heat exchange between the inlet and outlet water of the MVR evaporation system. Generally, a plate heat exchanger with high heat transfer efficiency is used. The purpose is to reduce the outlet water temperature while increasing the inlet water temperature to achieve the purpose of recovering the outlet water heat. At present, most of the inlet and outlet water heat exchangers of the MVR evaporation system adopt a single-stage design or a single-stage 1-for-1 design. In the field of wastewater treatment, the wastewater contains soluble solids. The materials are heat exchanged through the heat exchanger. Since the solubility of some materials at different temperatures is different, some solids in the wastewater will precipitate during the temperature increase. The plate heat exchanger has a compact structure and a narrow flow channel. After working for a long time, the precipitated solids gradually increase, causing the plate exchange to be blocked, and in severe cases, the system will shut down. Utility Model Content

[0003] In view of the above problems, the utility model proposes a two-stage heat exchange device based on an MVR evaporation system to solve the problem that the compact structure of the heat exchanger leads to narrow flow channels, and after long-term operation, the precipitated solids gradually increase, causing plate exchange blockage, and in severe cases causing system shutdown; To achieve the above purpose, the utility model provides a two-stage heat exchange device based on an MVR evaporation system, including:

[0004] A primary heat exchanger, a secondary heat exchanger A and a secondary heat exchanger B;

[0005] The cold side inlet of the primary heat exchanger is connected to the T10 feed pipe, and the cold side outlet is connected to the T11 feed main pipe. The T11 feed main pipe is divided into T11 feed pipe A and T11 feed pipe B. T11 feed pipe A is connected to the cold side feed port of the secondary heat exchanger A. The cold side outlet of the secondary heat exchanger A is connected to T12 feed pipe A. T11 feed pipe B is connected to the cold side feed port of the secondary heat exchanger B. The cold side outlet of the secondary heat exchanger B is connected to T12 feed pipe B. T12 feed pipe A and T12 feed pipe B are connected to the T12 feed main pipe after being combined. The T12 feed main pipe is connected to the MVR evaporation system.

[0006] The MVR evaporation system is connected to the T20 hot water main pipe. The T20 hot water main pipe is divided into T20 hot water pipe A and T20 hot water pipe B. T20 hot water pipe A is connected to the hot side feed port of the secondary heat exchanger A, and T20 hot water pipe B is connected to the hot side feed port of the secondary heat exchanger B. The hot side discharge port of the secondary heat exchanger A is connected to T21 hot water pipe A, and the hot side discharge port of the secondary heat exchanger B is connected to T21 hot water pipe B. T21 hot water pipe A and T21 hot water pipe B are connected to the T21 hot water main pipe after being collected. The T21 hot water main pipe is connected to the hot side feed port of the primary heat exchanger, and the hot side discharge port of the primary heat exchanger is connected to the T22 drain pipe.

[0007] Preferably, a feed flow meter is installed on the T10 feed pipe.

[0008] Preferably, an A feed valve is provided on the T11 feed pipe A, a B feed valve is provided on the T11 feed pipe B, an A discharge valve is provided on the T12 feed pipe A, and a B discharge valve is provided on the T12 feed pipe B.

[0009] Preferably, a first A hot water valve is arranged on the T20 hot water pipe A, a first B hot water valve is arranged on the T20 hot water pipe B, a second A hot water valve is arranged on the T21 hot water pipe A, and a second B hot water valve is arranged on the T21 hot water pipe B.

[0010] Preferably, the cleaning tank is connected to the cleaning agent pipe, and the cleaning tank is replenished with cleaning agent through the cleaning agent pipe.

[0011] Preferably, a cleaning flow meter is provided on the second cleaning pipe.

[0012] Preferably, a first A cleaning valve is arranged on the A inlet cleaning pipe, a first B cleaning valve is arranged on the B inlet cleaning pipe, a second A cleaning valve is arranged on the A return cleaning pipe, and a first B cleaning valve is arranged on the B return cleaning pipe.

[0013] Preferably, the secondary heat exchange device also includes: a first cleaning pipe is connected to the bottom of the cleaning tank, the first cleaning pipe is connected to the inlet of the cleaning pump, the outlet of the cleaning pump is connected to the second cleaning pipe, the second cleaning pipe is divided into an A inlet cleaning pipe and a B inlet cleaning pipe, the A inlet cleaning pipe is connected to the T11 feed pipe A, and the connection point is located on the pipeline between the A feed valve and the secondary heat exchanger A, the B inlet cleaning pipe is connected to the T11 feed pipe B, and the connection point is located on the pipeline between the B feed valve and the secondary heat exchanger B, the A return cleaning pipe is connected to the T12 feed pipe A between the cold side discharge port of the secondary heat exchanger A and the A discharge valve, the B return cleaning pipe is connected to the T12 feed pipe B between the cold side discharge port of the secondary heat exchanger B and the B discharge valve, the A return cleaning pipe and the B return cleaning pipe are connected to the total return cleaning pipe, and the total return cleaning pipe is connected to the cleaning tank.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] The patented two-stage heat exchanger can operate more stably in the field of wastewater treatment, with a lower chance of blockage; it saves more equipment investment and replacement of wearing parts, and when blocked, fewer heat exchange plates need to be cleaned, and the blockage is cleared faster. The heat exchanger has a compact structure and more flow channels. After working for a long time, the plate exchange will not be blocked or cause the system to shut down, and the operation is more stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the two-stage heat exchange device.

[0017] Figure 2 Schematic diagram of the heat exchanger.

[0018] In the figure: 11, feed flow meter; 12, primary heat exchanger; 13, secondary heat exchanger A; 14, secondary heat exchanger B; 15, MVR evaporation system; 16, cleaning flow meter; 17, cleaning tank; 18, cleaning pump;

[0019] 21. T10 feed pipe; 22. T11 main feed pipe; 23. T11 feed pipe A; 24. T11 feed pipe B; 25. T12 feed pipe A; 26. T12 feed pipe B; 27. T12 main feed pipe;

[0020] 31. T20 hot water main; 32. T20 hot water pipe A; 33. T20 hot water pipe B; 34. T21 hot water pipe A; 35. T21 hot water pipe B; 36. T21 hot water main; 37. T22 drainage pipe;

[0021] 40, cleaning agent pipe; 41, first cleaning pipe; 42, second cleaning pipe; 43, A inlet cleaning pipe; 44, B inlet cleaning pipe; 45, B return cleaning pipe; 46, A return cleaning pipe; 47, total return cleaning pipe;

[0022] 51. First A cleaning valve; 52. First B cleaning valve; 53. Second A cleaning valve; 54. Second B cleaning valve; 61. A feed valve; 62. B feed valve; 63. A discharge valve; 64. B discharge valve; 71. First A hot water valve; 72. First B hot water valve; 73. Second A hot water valve; 74. Second B hot water valve; 81. Cold side feed port of heat exchanger; 82. Cold side discharge port of heat exchanger; 83. Hot side discharge port of heat exchanger; 84. Hot side feed port of heat exchanger. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, which are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation of the present utility model. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances. The following is an explanation of the embodiments of the present utility model based on the overall structure of the present utility model.

[0025] See also Figure 1-Figure 2 The utility model provides a technical solution: a two-stage heat exchange device based on an MVR evaporation system, comprising: a primary heat exchanger 12, a secondary heat exchanger A13, a secondary heat exchanger B14, and switch valves arranged before and after the heat exchanger.

[0026] Connection of feed pipeline: The material with temperature T10 first enters T10 feed pipe 21, on which feed flow meter 11 is installed, and then connected to the cold side inlet of primary heat exchanger 12, and the cold side outlet of primary heat exchanger 12 is connected to T11 feed main pipe 22, and T11 feed main pipe 22 is further divided into two pipes, one of which is T11 feed pipe A23 connected to the cold side feed port of secondary heat exchanger A13, and the other is T11 feed pipe B24 connected to the cold side feed port of secondary heat exchanger B14, and the secondary heat exchanger The cold side outlet of the heat exchanger A13 is connected to the T12 feed pipe A25, and the cold side outlet of the secondary heat exchanger B14 is connected to the T12 feed pipe B26. After the T12 feed pipe A25 is connected to the T12 feed pipe B26, it enters the MVR evaporation system 15 through the T12 feed main pipe 27. The T11 feed pipe A23 is equipped with an A feed valve 61, the T11 feed pipe B24 is equipped with a B feed valve 62, the T12 feed pipe A25 is equipped with an A discharge valve 63, and the T12 feed pipe B26 is equipped with a B discharge valve 64.

[0027] Connection of hot water pipeline: The hot water discharged from the MVR evaporation system 15 first enters the T20 hot water main pipe 31, and the T20 hot water main pipe 31 is further divided into two pipes, one of which is the T20 hot water pipe A32 entering the hot side feed port of the secondary heat exchanger A13, and the other is the T20 hot water pipe B33 entering the hot side feed port of the secondary heat exchanger B14. The hot side discharge port of the secondary heat exchanger A13 is connected to the T21 hot water pipe A34, and the hot side discharge port of the secondary heat exchanger B14 is connected to the T21 hot water pipe B35. , T21 hot water pipe A34 and T21 hot water pipe B35 are connected to T21 hot water main pipe 36, T21 hot water main pipe 36 is connected to the hot side feed port of the first-level heat exchanger 12, the hot side discharge port of the first-level heat exchanger 12 is connected to T22 drain pipe 37, the T20 hot water pipe A32 is equipped with a first A hot water valve 71, the T20 hot water pipe B33 is equipped with a first B hot water valve 72, the T21 hot water pipe A34 is equipped with a second A hot water valve 73, and the T21 hot water pipe B35 is equipped with a second B hot water valve 74.

[0028] Connection of cleaning pipeline: The cleaning tank 17 is replenished with cleaning agent through the cleaning agent pipe 40. The bottom of the cleaning tank 17 is connected to the inlet of the cleaning pump 18 through the first cleaning pipe 41. The outlet of the cleaning pump 18 is connected to the second cleaning pipe 42. The second cleaning pipe 42 is equipped with a cleaning flow meter 16. The second cleaning pipe 42 is divided into two pipes, one of which is an A cleaning pipe 43 connected to the T11 feed pipe A23, and the connection point is located on the pipe between the A feed valve 61 and the secondary heat exchanger A13. The other B cleaning pipe 44 is connected to the T11 feed pipe B24, and the connection point is located between the B feed valve 62 and the secondary heat exchanger B14 On the pipeline, the A return cleaning pipe 46 is connected to the T12 feed pipe A25 between the cold side discharge port of the secondary heat exchanger A13 and the A discharge valve 63, and the B return cleaning pipe 45 is connected to the T12 feed pipe B26 between the cold side discharge port of the secondary heat exchanger B14 and the B discharge valve 64. The A return cleaning pipe 46 and the B return cleaning pipe 45 are connected to the total return cleaning pipe 47 and then connected to the cleaning tank 17. The A inlet cleaning pipe 43 is equipped with a first A cleaning valve 51, the B inlet cleaning pipe 44 is equipped with a first B cleaning valve 52, the A return cleaning pipe 46 is equipped with a second A cleaning valve 53, and the B return cleaning pipe 45 is equipped with a first B cleaning valve 52.

[0029] The primary heat exchanger 12 , the secondary heat exchanger A13 , and the secondary heat exchanger B14 are all composed of: a heat exchanger cold side feed inlet 81 , a heat exchanger cold side discharge inlet 82 , a heat exchanger hot side discharge inlet 83 , and a heat exchanger hot side feed inlet 84 .

[0030] Working process of the secondary heat exchanger:

[0031] After the material with a temperature of T10 passes through the feed flow meter 11, it is transported to the primary heat exchanger 12, and heat exchanges with the hot water of the discharge system. After the temperature rises to the set temperature T11, it is discharged from the cold side of the primary heat exchanger 12, enters the cold side feed port of the secondary heat exchanger, and heat exchanges with the hot water discharged from the MVR evaporation system 15. After the temperature rises to the set temperature T12, it is discharged from the cold side discharge port of the secondary heat exchanger and enters the MVR evaporation system 15. The hot water produced from the MVR evaporation system 15 has a temperature of T20, enters the hot side feed port of the secondary heat exchanger, and after heat exchange with the feed of the secondary heat exchanger, the temperature drops to T21, and is discharged from the hot side discharge port of the secondary heat exchanger, enters the hot side feed port of the primary heat exchanger 12, and then heat exchanges with the feed of the primary heat exchanger 12. After the temperature drops to T22, it is discharged.

[0032] The secondary heat exchanger adopts a 1-in-1 configuration. When the secondary heat exchanger A13 is working, the A feed valve 61, the A discharge valve 63, the first A hot water valve 71, and the second A hot water valve 73 are in the open state, and the first A cleaning valve 51, the second A cleaning valve 53, the B feed valve 62, the B discharge valve 64, the first B hot water valve 72, and the second B hot water valve 74 are in the closed state. When the secondary heat exchanger B14 is working, the B feed valve 62, the B discharge valve 64, the first B hot water valve 72, and the second B hot water valve 74 are in the open state, and the first B cleaning valve 52, the second B cleaning valve 54, the A feed valve 61, the A discharge valve 63, the B discharge valve 64, the first A hot water valve 71, and the second A hot water valve 73 are in the closed state.

[0033] Timing of switching the secondary heat exchanger: According to the parameters fed back by the feed flow meter 11, when the set value is reached, it is determined that the currently working heat exchanger is blocked and can be switched to another heat exchanger; optionally, the switching timing can also be determined based on the pressure difference set before and after the secondary heat exchanger; optionally, the switching timing can also be determined based on the temperature meter parameters set on the pipes before and after the secondary heat exchanger.

[0034] When the secondary heat exchanger A13 is working, the secondary heat exchanger B14 can start online chemical cleaning, open the first B cleaning valve 52 and the second B cleaning valve 54, and start the cleaning pump 18 to perform cyclic cleaning of the secondary heat exchanger B14. Similarly, when the secondary heat exchanger B14 is working, the secondary heat exchanger A13 can start online chemical cleaning, open the first A cleaning valve 51 and the second A cleaning valve 53, and start the cleaning pump 18 to perform cyclic cleaning of the secondary heat exchanger A13. Determination of the cleaning effect of the heat exchanger: According to the parameters fed back by the cleaning flow meter 16, when the set value is reached, it is determined that the heat exchanger currently being cleaned is unobstructed; the cleaning effect can also be determined according to the pressure difference set before and after the secondary heat exchanger.

[0035] Compared with conventional single-stage heat exchangers, this two-stage heat exchanger can operate more stably in the field of wastewater treatment, with a lower chance of clogging; this two-stage heat exchanger saves more equipment investment and replacement of wearing parts, and when blocked, fewer heat exchange plates need to be cleaned, and the blockage is cleared faster. The heat exchanger has a compact structure and more flow channels. After working for a long time, the plate exchange will not be blocked or cause the system to shut down, and the operation is more stable.

[0036] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the appended claims rather than the above description. Therefore, it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention, and any figure marks in the claims should not be regarded as limiting the claims involved.

Claims

1. A two-stage heat exchange device based on an MVR evaporation system, characterized in that: include: a primary heat exchanger (12), a secondary heat exchanger A (13) and a secondary heat exchanger B (14); The cold side inlet of the primary heat exchanger (12) is connected to the T10 feed pipe (21), and the cold side outlet is connected to the T11 feed main pipe (22). The T11 feed main pipe (22) is divided into a T11 feed pipe A (23) and a T11 feed pipe B (24). The T11 feed pipe A (23) is connected to the cold side feed port of the secondary heat exchanger A (13). The cold side outlet of the secondary heat exchanger A (13) is connected to the T12 feed port. The feed pipe A (25) and the T11 feed pipe B (24) are connected to the cold side feed port of the secondary heat exchanger B (14); the cold side discharge port of the secondary heat exchanger B (14) is connected to the T12 feed pipe B (26); the T12 feed pipe A (25) and the T12 feed pipe B (26) are connected to the T12 feed main pipe (27); and the T12 feed main pipe (27) is connected to the MVR evaporation system (15); The MVR evaporation system (15) is connected to a T20 hot water main (31). The T20 hot water main (31) is divided into a T20 hot water pipe A (32) and a T20 hot water pipe B (33). The T20 hot water pipe A (32) is connected to a hot side feed port of a secondary heat exchanger A (13). The T20 hot water pipe B (33) is connected to a hot side feed port of a secondary heat exchanger B (14). The hot side discharge port of the secondary heat exchanger A (13) is connected to a T21 hot water pipe A (34). The hot side discharge port of the secondary heat exchanger B (14) is connected to a T21 hot water pipe B (35). The T21 hot water pipe A (34) and the T21 hot water pipe B (35) are connected to a T21 hot water main (36) after being collected. The T21 hot water main (36) is connected to a hot side feed port of a primary heat exchanger (12). The hot side discharge port of the primary heat exchanger (12) is connected to a T22 drain pipe (37).

2. The two-stage heat exchange device based on the MVR evaporation system according to claim 1 is characterized in that: The secondary heat exchange device further comprises a cleaning tank (17), the bottom of which is connected to a first cleaning pipe (41), the first cleaning pipe (41) is connected to the inlet of a cleaning pump (18), the outlet of the cleaning pump (18) is connected to a second cleaning pipe (42), the second cleaning pipe (42) is divided into an A inlet cleaning pipe (43) and a B inlet cleaning pipe (44), the A inlet cleaning pipe (43) is connected to a T11 feed pipe A (23), the connection point of which is located on the pipeline between an A feed valve (61) and the secondary heat exchanger A (13), the B inlet cleaning pipe (44) is connected to a T11 feed pipe B (24), The connection point is located on the pipeline between the B feed valve (62) and the secondary heat exchanger B (14); the A return cleaning pipe (46) is connected to the T12 feed pipe A (25) between the cold side discharge port of the secondary heat exchanger A (13) and the A discharge valve (63); the B return cleaning pipe (45) is connected to the T12 feed pipe B (26) between the cold side discharge port of the secondary heat exchanger B (14) and the B discharge valve (64); the A return cleaning pipe (46) and the B return cleaning pipe (45) are connected to the main return cleaning pipe (47); and the main return cleaning pipe (47) is connected to the cleaning tank (17).

3. The two-stage heat exchange device based on the MVR evaporation system according to claim 1 is characterized in that: A feed flow meter (11) is installed on the T10 feed pipe (21).

4. The two-stage heat exchange device based on the MVR evaporation system according to claim 1 is characterized in that: The T11 feed pipe A (23) is provided with an A feed valve (61), the T11 feed pipe B (24) is provided with a B feed valve (62), the T12 feed pipe A (25) is provided with an A discharge valve (63), and the T12 feed pipe B (26) is provided with a B discharge valve (64).

5. The two-stage heat exchange device based on the MVR evaporation system according to claim 1 is characterized in that: The T20 hot water pipe A (32) is provided with a first A hot water valve (71), the T20 hot water pipe B (33) is provided with a first B hot water valve (72), the T21 hot water pipe A (34) is provided with a second A hot water valve (73), and the T21 hot water pipe B (35) is provided with a second B hot water valve (74).

6. The two-stage heat exchange device based on the MVR evaporation system according to claim 2 is characterized in that: The cleaning tank (17) is connected to a cleaning agent pipe (40), and the cleaning tank (17) is replenished with cleaning agent through the cleaning agent pipe (40).

7. The two-stage heat exchange device based on the MVR evaporation system according to claim 2 is characterized in that: A cleaning flow meter (16) is provided on the second cleaning pipe (42).

8. The two-stage heat exchange device based on the MVR evaporation system according to claim 2 is characterized in that: The A inlet cleaning pipe (43) is provided with a first A cleaning valve (51), the B inlet cleaning pipe (44) is provided with a first B cleaning valve (52), the A return cleaning pipe (46) is provided with a second A cleaning valve (53), and the B return cleaning pipe (45) is provided with a first B cleaning valve (52).

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