A microchannel heat exchanger pulse flushing system and method

Abstract

The present invention discloses a pulse flushing system and method for a microchannel heat exchanger. The system belongs to a closed cleaning system. The working pressure does not need to be too high. In principle, only the resistance pressure drop of the high-pressure heat exchanger is required, which must be lower than the design pressure of the heat exchanger. The system has simple equipment, easy operation, and can be operated fully automatically. In addition, since pulse flushing is adopted instead of traditional constant flow constant pressure flushing, and the flushing process is a combination of forward flushing and reverse flushing, dirt and residues can be easily fallen off during the oscillation process, the cleaning time is short, and the effect is good.

Description

Technical Field

[0001] The invention relates to the technical field of heat exchanger cleaning, and in particular to a pulse flushing system and method for a microchannel heat exchanger. Background Art

[0002] Printed circuit heat exchanger (PCHE) belongs to the category of microchannel plate heat exchanger. PCHE has the advantages of compact structure, high temperature resistance, high pressure resistance, safety and reliability, and is widely used in refrigeration and air conditioning, petroleum and natural gas, nuclear industry, chemical industry, power industry and other fields.

[0003] However, this heat exchanger also has some defects when in use. The main problem is that the PCHE heat exchanger channel is too small and is very easy to be blocked, and once blocked, it is difficult to clean. The current cleaning method is to flush the heat exchanger with a very high-pressure cleaning liquid. The pressure is high, the flushing time is long, and the impurities in some dead zones are still difficult to clean. Therefore, it is hoped to invent a simpler cleaning device and cleaning method with a shorter cleaning time. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a microchannel heat exchanger pulse flushing system and method, which can simply and effectively clean the microchannel heat exchanger without too high pressure, short cleaning time and good effect.

[0005] In order to achieve the above object, the present invention adopts the following technical scheme:

[0006] A microchannel heat exchanger pulse flushing system, comprising a liquid storage tank 1, a high-pressure pump 2, a bypass pneumatic shut-off valve 3, a bypass pressure reducing valve 4, a high-pressure storage tank 5, a safety valve 6, a first forward flushing circuit pneumatic shut-off valve 7, a forward flushing circuit check valve 8, a first reverse flushing circuit pneumatic shut-off valve 9, a reverse flushing circuit check valve 10, a microchannel heat exchanger 11, a first reverse flushing circuit manual shut-off valve 12, a reverse flushing circuit filter 13, a second reverse flushing circuit manual shut-off valve 14, a second reverse flushing circuit pneumatic shut-off valve 15, a first forward flushing circuit manual shut-off valve 16, a forward flushing circuit filter 17, a second forward flushing circuit manual shut-off valve 18, and a second forward flushing circuit pneumatic shut-off valve 19;

[0007] The liquid outlet of the liquid storage tank 1 is connected to the inlet of the high-pressure pump 2. The outlet of the high-pressure pump 2 is divided into two paths, one of which is connected to the inlet of the bypass pneumatic shut-off valve 3. The outlet of the bypass pneumatic shut-off valve 3 is connected to the inlet of the bypass pressure reducing valve 4. The outlet of the bypass pressure reducing valve 4 is connected to the liquid return port of the liquid storage tank 1. The other outlet of the high-pressure pump 2 is connected to the inlet of the high-pressure storage tank 5. A safety valve 6 is installed on the top of the high-pressure storage tank 5. The outlet of the safety valve 6 is also connected to the liquid return port of the liquid storage tank 1. The outlet of the high-pressure storage tank 5 is divided into two paths, one of which is connected to the first forward flushing circuit. The inlet of the pneumatic shut-off valve 7 is connected, the outlet of the second forward flushing circuit pneumatic shut-off valve 7 is connected to the inlet of the forward flushing circuit check valve 8, the outlet of the forward flushing circuit check valve 8 is connected to the forward flushing inlet of the microchannel heat exchanger 11, the forward flushing outlet of the microchannel heat exchanger 11 is connected to the inlet of the first forward flushing circuit manual shut-off valve 16, the outlet of the first forward flushing circuit manual shut-off valve 16 is connected to the inlet of the forward flushing circuit filter 17, and the outlet of the forward flushing circuit filter 17 is connected to the second forward flushing circuit manual shut-off valve The inlet of the valve 18 is connected, the outlet of the second forward flushing circuit manual stop valve 18 is connected to the inlet of the second forward flushing circuit pneumatic shut-off valve 19, the outlet of the second forward flushing circuit pneumatic shut-off valve 19 is also connected to the return liquid port of the liquid storage tank 1, the other way of the outlet of the high-pressure storage tank 5 is connected to the inlet of the first reverse flushing circuit pneumatic shut-off valve 9, the outlet of the first reverse flushing circuit pneumatic shut-off valve 9 is connected to the inlet of the reverse flushing circuit check valve 10, the outlet of the reverse flushing circuit check valve 10 is connected to the reverse flushing inlet of the microchannel heat exchanger 11 The reverse flushing outlet of the microchannel heat exchanger 11 is connected to the inlet of the first reverse flushing circuit manual stop valve 12, the outlet of the first reverse flushing circuit manual stop valve 12 is connected to the inlet of the reverse flushing circuit filter 13, the outlet of the reverse flushing circuit filter 13 is connected to the second reverse flushing circuit manual stop valve 14, the outlet of the second reverse flushing circuit manual stop valve 14 is connected to the inlet of the second reverse flushing circuit pneumatic shut-off valve 15, and the outlet of the second reverse flushing circuit pneumatic shut-off valve 15 is also connected to the return liquid port of the liquid storage tank 1.

[0008] The flushing method of the microchannel heat exchanger pulse flushing system is as follows: at the beginning of flushing, the bypass pneumatic shut-off valve 3, the bypass pressure reducing valve 4, the first forward flushing circuit pneumatic shut-off valve 7, the first reverse flushing circuit manual shut-off valve 12, the second reverse flushing circuit manual shut-off valve 14, the first forward flushing circuit manual shut-off valve 16, the second forward flushing circuit manual shut-off valve 218 and the second forward flushing circuit pneumatic shut-off valve 19 are first opened, and the first reverse flushing circuit pneumatic shut-off valve 9 and the second reverse flushing circuit pneumatic shut-off valve 15 are closed; then the high-pressure pump 2 is turned on to establish flow in the system; then the first forward flushing circuit pneumatic shut-off valve 7 and the second forward flushing circuit pneumatic shut-off valve 19 are closed. The pneumatic shut-off valve 19 of the flushing circuit allows all flushing liquid to flow through the bypass; the bypass pressure reducing valve 4 is gradually adjusted to gradually increase the pressure of the high-pressure storage tank 5 until the predetermined flushing pressure is reached; then the first forward flushing circuit pneumatic shut-off valve 7 and the second forward flushing circuit pneumatic shut-off valve 19 are opened at the same time, and the bypass pneumatic shut-off valve 3 is closed at the same time, completing a forward pulse flushing; when the pressure of the high-pressure storage tank 5 drops to the set value, the first forward flushing circuit pneumatic shut-off valve 7 and the second forward flushing circuit pneumatic shut-off valve 19 are closed at the same time, and the bypass pneumatic shut-off valve 3 is opened at the same time, so that the pressure of the high-pressure storage tank 5 increases again until the predetermined flushing pressure is reached, and then the forward flushing operation is repeated;

[0009] After 3-5 times of forward flushing, start reverse flushing, and at the same time close the first forward flushing circuit pneumatic shut-off valve 7 and the second forward flushing circuit pneumatic shut-off valve 19, and at the same time open the bypass pneumatic shut-off valve 3, so that the pressure of the high-pressure storage tank 5 increases again until the predetermined flushing pressure; then open the first reverse flushing circuit pneumatic shut-off valve 9 and the second reverse flushing circuit pneumatic shut-off valve 15 at the same time, and at the same time close the bypass pneumatic shut-off valve 3 to complete a reverse pulse flushing; then continue 3-5 times of forward flushing, and then switch to reverse flushing again, until the heat exchanger cleaning meets the standards.

[0010] The present invention has the following beneficial effects:

[0011] The present invention discloses a microchannel heat exchanger pulse flushing system and method. The system belongs to a closed cleaning system. The working pressure does not need to be too high. In principle, only the resistance pressure drop of the high-pressure heat exchanger is required, which must be lower than the design pressure of the heat exchanger. The system has simple equipment, easy operation, and can be operated fully automatically. Moreover, since pulse flushing is adopted instead of the traditional constant flow constant pressure flushing, and the flushing process is a combination of forward flushing and reverse flushing, dirt and residue can be easily fallen off during the oscillation process, the cleaning time is short, and the effect is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the structure of the system of the present invention.

[0013] Among them, there are a liquid storage tank 1, a high-pressure pump 2, a bypass pneumatic shut-off valve 3, a bypass pressure reducing valve 4, a high-pressure storage tank 5, a safety valve 6, a first forward flushing circuit pneumatic shut-off valve 7, a forward flushing circuit check valve 8, a first reverse flushing circuit pneumatic shut-off valve 9, a reverse flushing circuit check valve 10, a microchannel heat exchanger 11, a first reverse flushing circuit manual shut-off valve 12, a reverse flushing circuit filter 13, a second reverse flushing circuit manual shut-off valve 14, a reverse flushing circuit pneumatic shut-off valve 15, a first forward flushing circuit manual shut-off valve 16, a forward flushing circuit filter 17, a second forward flushing circuit manual shut-off valve 18, and a second forward flushing circuit pneumatic shut-off valve 19. DETAILED DESCRIPTION

[0014] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0015] refer to Figure 1 The present invention provides a pulse flushing system for a microchannel heat exchanger, comprising a liquid storage tank 1, a high-pressure pump 2, a bypass pneumatic shut-off valve 3, a bypass pressure reducing valve 4, a high-pressure storage tank 5, a safety valve 6, a first forward flushing circuit pneumatic shut-off valve 7, a forward flushing circuit check valve 8, a first reverse flushing circuit pneumatic shut-off valve 9, a reverse flushing circuit check valve 10, a microchannel heat exchanger 11, a first reverse flushing circuit manual shut-off valve 12, a reverse flushing circuit filter 13, a second reverse flushing circuit manual shut-off valve 14, a second reverse flushing circuit pneumatic shut-off valve 15, a first forward flushing circuit manual shut-off valve 16, a forward flushing circuit filter 17, a second forward flushing circuit manual shut-off valve 18, and a second forward flushing circuit pneumatic shut-off valve 19;

[0016] The liquid outlet of the liquid storage tank 1 is connected to the inlet of the high-pressure pump 2. The outlet of the high-pressure pump 2 is divided into two paths, one of which is connected to the inlet of the bypass pneumatic shut-off valve 3. The outlet of the bypass pneumatic shut-off valve 3 is connected to the inlet of the bypass pressure reducing valve 4. The outlet of the bypass pressure reducing valve 4 is connected to the liquid return port of the liquid storage tank 1. The other outlet of the high-pressure pump 2 is connected to the inlet of the high-pressure storage tank 5. A safety valve 6 is installed on the top of the high-pressure storage tank 5. The outlet of the safety valve 6 is also connected to the liquid return port of the liquid storage tank 1. The outlet of the high-pressure storage tank 5 is divided into two paths, one of which is connected to the first forward flushing circuit. The inlet of the pneumatic shut-off valve 7 is connected, the outlet of the second forward flushing circuit pneumatic shut-off valve 7 is connected to the inlet of the forward flushing circuit check valve 8, the outlet of the forward flushing circuit check valve 8 is connected to the forward flushing inlet of the microchannel heat exchanger 11, the forward flushing outlet of the microchannel heat exchanger 11 is connected to the inlet of the first forward flushing circuit manual shut-off valve 16, the outlet of the first forward flushing circuit manual shut-off valve 16 is connected to the inlet of the forward flushing circuit filter 17, and the outlet of the forward flushing circuit filter 17 is connected to the second forward flushing circuit manual shut-off valve The inlet of the valve 18 is connected, the outlet of the second forward flushing circuit manual stop valve 18 is connected to the inlet of the second forward flushing circuit pneumatic shut-off valve 19, the outlet of the second forward flushing circuit pneumatic shut-off valve 19 is also connected to the return liquid port of the liquid storage tank 1, the other way of the outlet of the high-pressure storage tank 5 is connected to the inlet of the first reverse flushing circuit pneumatic shut-off valve 9, the outlet of the first reverse flushing circuit pneumatic shut-off valve 9 is connected to the inlet of the reverse flushing circuit check valve 10, the outlet of the reverse flushing circuit check valve 10 is connected to the reverse flushing inlet of the microchannel heat exchanger 11 The reverse flushing outlet of the microchannel heat exchanger 11 is connected to the inlet of the first reverse flushing circuit manual stop valve 12, the outlet of the first reverse flushing circuit manual stop valve 12 is connected to the inlet of the reverse flushing circuit filter 13, the outlet of the reverse flushing circuit filter 13 is connected to the second reverse flushing circuit manual stop valve 14, the outlet of the second reverse flushing circuit manual stop valve 14 is connected to the inlet of the second reverse flushing circuit pneumatic shut-off valve 15, and the outlet of the second reverse flushing circuit pneumatic shut-off valve 15 is also connected to the return liquid port of the liquid storage tank 1.

[0017] like Figure 1As shown, a flushing method for a pulse flushing system of a microchannel heat exchanger of the present invention is firstly opened at the beginning of flushing, the bypass pneumatic shut-off valve 3, the bypass pressure reducing valve 4, the first forward flushing circuit pneumatic shut-off valve 7, the first reverse flushing circuit manual shut-off valve 12, the second reverse flushing circuit manual shut-off valve 14, the first forward flushing circuit manual shut-off valve 16, the second forward flushing circuit manual shut-off valve 218 and the second forward flushing circuit pneumatic shut-off valve 19, and the first reverse flushing circuit pneumatic shut-off valve 9 and the second reverse flushing circuit pneumatic shut-off valve 15 are closed; then the high-pressure pump 2 is started to establish flow in the system; then the first forward flushing circuit pneumatic shut-off valve 7 and the second forward flushing circuit pneumatic shut-off valve 19 are closed. The pneumatic shut-off valve 19 of the forward flushing circuit allows all the flushing liquid to flow through the bypass; the bypass pressure reducing valve 4 is gradually adjusted to gradually increase the pressure of the high-pressure storage tank 5 until the predetermined flushing pressure is reached; then the first forward flushing circuit pneumatic shut-off valve 7 and the second forward flushing circuit pneumatic shut-off valve 19 are opened at the same time, and the bypass pneumatic shut-off valve 3 is closed at the same time, completing a forward pulse flushing; when the pressure of the high-pressure storage tank 5 drops to the set value, the first forward flushing circuit pneumatic shut-off valve 7 and the second forward flushing circuit pneumatic shut-off valve 19 are closed at the same time, and the bypass pneumatic shut-off valve 3 is opened at the same time, so that the pressure of the high-pressure storage tank 5 increases again until the predetermined flushing pressure is reached, and then the forward flushing operation is repeated;

[0018] After 3-5 times of forward flushing, start reverse flushing, and at the same time close the first forward flushing circuit pneumatic shut-off valve 7 and the second forward flushing circuit pneumatic shut-off valve 19, and at the same time open the bypass pneumatic shut-off valve 3, so that the pressure of the high-pressure storage tank 5 increases again until the predetermined flushing pressure; then open the first reverse flushing circuit pneumatic shut-off valve 9 and the second reverse flushing circuit pneumatic shut-off valve 15 at the same time, and at the same time close the bypass pneumatic shut-off valve 3 to complete a reverse pulse flushing; then continue 3-5 times of forward flushing, and then switch to reverse flushing again, until the heat exchanger cleaning meets the standards.

[0019] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A flushing method for a pulse flushing system of a microchannel heat exchanger, characterized in that: The system comprises a liquid storage tank (1), a high-pressure pump (2), a bypass pneumatic shut-off valve (3), a bypass pressure reducing valve (4), a high-pressure storage tank (5), a safety valve (6), a first forward flushing circuit pneumatic shut-off valve (7), a forward flushing circuit check valve (8), a first reverse flushing circuit pneumatic shut-off valve (9), a reverse flushing circuit check valve (10), a microchannel heat exchanger (11), a first reverse flushing circuit manual shut-off valve (12), a reverse flushing circuit filter (13), a second reverse flushing circuit manual shut-off valve (14), a second reverse flushing circuit pneumatic shut-off valve (15), a first forward flushing circuit manual shut-off valve (16), a forward flushing circuit filter (17), a second forward flushing circuit manual shut-off valve (18), and a second forward flushing circuit pneumatic shut-off valve (19); The liquid outlet of the liquid storage tank (1) is connected to the inlet of the high-pressure pump (2). The outlet of the high-pressure pump (2) is divided into two paths, one of which is connected to the inlet of the bypass pneumatic shut-off valve (3). The outlet of the bypass pneumatic shut-off valve (3) is connected to the inlet of the bypass pressure reducing valve (4). The outlet of the bypass pressure reducing valve (4) is connected to the liquid return port of the liquid storage tank (1). The other outlet of the high-pressure pump (2) is connected to the inlet of the high-pressure storage tank (5). A safety valve (6) is installed on the top of the high-pressure storage tank (5). The outlet of the safety valve (6) is also connected to the liquid return port of the liquid storage tank (1). The outlet of the high-pressure storage tank (5) is divided into two paths, one of which is connected to the first The inlet of a forward flushing circuit pneumatic shut-off valve (7) is connected, the outlet of a second forward flushing circuit pneumatic shut-off valve (19) is connected to the inlet of a forward flushing circuit check valve (8), the outlet of the forward flushing circuit check valve (8) is connected to the forward flushing inlet of a microchannel heat exchanger (11), the forward flushing outlet of the microchannel heat exchanger (11) is connected to the inlet of a first forward flushing circuit manual shut-off valve (16), the outlet of the first forward flushing circuit manual shut-off valve (16) is connected to the inlet of a forward flushing circuit filter (17), the outlet of the forward flushing circuit filter (17) is connected to the second forward flushing circuit manual shut-off valve (19), and the outlet of the forward flushing circuit filter (17) is connected to the inlet of a second forward flushing circuit manual shut-off valve (19). The inlet of the manual stop valve (18) is connected, the outlet of the second forward flushing circuit manual stop valve (18) is connected to the inlet of the second forward flushing circuit pneumatic shut-off valve (19), the outlet of the second forward flushing circuit pneumatic shut-off valve (19) is also connected to the liquid return port of the liquid storage tank (1), the other outlet of the high-pressure storage tank (5) is connected to the inlet of the first reverse flushing circuit pneumatic shut-off valve (9), the outlet of the first reverse flushing circuit pneumatic shut-off valve (9) is connected to the inlet of the reverse flushing circuit check valve (10), the outlet of the reverse flushing circuit check valve (10) is connected to the reverse flushing circuit of the microchannel heat exchanger (11) The backwash inlet of the microchannel heat exchanger (11) is connected to the inlet of the first backwashing circuit manual shut-off valve (12), the outlet of the first backwashing circuit manual shut-off valve (12) is connected to the inlet of the backwashing circuit filter (13), the outlet of the backwashing circuit filter (13) is connected to the second backwashing circuit manual shut-off valve (14), the outlet of the second backwashing circuit manual shut-off valve (14) is connected to the inlet of the second backwashing circuit pneumatic shut-off valve (15), and the outlet of the second backwashing circuit pneumatic shut-off valve (15) is also connected to the liquid return port of the liquid storage tank (1); The flushing method comprises: when flushing starts, firstly opening the bypass pneumatic shut-off valve (3), the bypass pressure reducing valve (4), the first forward flushing circuit pneumatic shut-off valve (7), the first reverse flushing circuit manual shut-off valve (12), the second reverse flushing circuit manual shut-off valve (14), the first forward flushing circuit manual shut-off valve (16), the second forward flushing circuit manual shut-off valve (18) and the second forward flushing circuit pneumatic shut-off valve (19), and closing the first reverse flushing circuit pneumatic shut-off valve (9) and the second reverse flushing circuit pneumatic shut-off valve (15); then starting the high-pressure pump (2) to establish flow in the system; then closing the first forward flushing circuit pneumatic shut-off valve (7) and the second forward flushing circuit pneumatic shut-off valve (19); The shut-off valve (19) allows all flushing liquid to flow through the bypass; the bypass pressure reducing valve (4) is gradually adjusted to gradually increase the pressure of the high-pressure storage tank (5) until the predetermined flushing pressure is reached; then the first forward flushing circuit pneumatic shut-off valve (7) and the second forward flushing circuit pneumatic shut-off valve (19) are opened simultaneously, and the bypass pneumatic shut-off valve (3) is closed simultaneously, completing a forward pulse flushing; when the pressure of the high-pressure storage tank (5) drops to the set value, the first forward flushing circuit pneumatic shut-off valve (7) and the second forward flushing circuit pneumatic shut-off valve (19) are closed simultaneously, and the bypass pneumatic shut-off valve (3) is opened simultaneously, so that the pressure of the high-pressure storage tank (5) is increased again until the predetermined flushing pressure is reached, and then the forward flushing operation is repeated; After 3-5 times of forward flushing, reverse flushing is started, and the first forward flushing circuit pneumatic shut-off valve (7) and the second forward flushing circuit pneumatic shut-off valve (19) are closed at the same time, and the bypass pneumatic shut-off valve (3) is opened at the same time, so that the pressure of the high-pressure storage tank (5) is increased again until the predetermined flushing pressure is reached; then the first reverse flushing circuit pneumatic shut-off valve (9) and the second reverse flushing circuit pneumatic shut-off valve (15) are opened at the same time, and the bypass pneumatic shut-off valve (3) is closed at the same time, completing a reverse pulse flushing; then 3-5 times of forward flushing are continued, and reverse flushing is switched again, until the heat exchanger cleaning meets the standard.

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