Absorption unit adopting falling film regenerator

Abstract

The utility model belongs to the technical field of heat exchange equipment, and particularly relates to an absorption type device adopting a falling film regenerator. Comprising an absorber, an evaporator, a condenser, a low-temperature regenerator, a high-temperature regenerator, a low-temperature heat exchanger, a high-temperature heat exchanger, a refrigerant condensate heat recovery device, a low-temperature heat regenerator, a drainage device, a high-temperature heat regenerator, a dilute solution pump, a concentrated solution pump and a refrigerant pump, and the high-temperature regenerator and the low-temperature regenerator adopt solution falling film structure units. The heat exchange efficiency of solution and steam is effectively improved, heat of heat source steam is fully recycled, the low-temperature regenerator is of a falling film heat exchange structure, the refrigerant water storage amount in a heat transfer pipe of the low-temperature regenerator is reduced, the refrigerant evaporation efficiency in the high-temperature regenerator is improved, the solution filling amount in the regenerator is effectively reduced, and the unit cost is greatly reduced; and high-temperature heat return and low-temperature heat return are adopted to recover steam condensate heat, efficient recovery of heat source steam heat is achieved, and the use safety of the unit is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of heat exchange equipment, and specifically relates to an absorption unit adopting a falling film regenerator. Background Art

[0002] The high-temperature regenerator of the steam-type lithium bromide absorption unit usually adopts a solution-immersed structure to exchange heat with the heat source. The regenerator immersed heat exchange structure cannot efficiently recover the heat of the heat source steam. The immersed regenerator needs to be filled with a large amount of solution, which causes an increase in the cost of the unit. How to improve the heat exchange efficiency of the steam-type lithium bromide absorption unit, reduce the solution filling amount, and solve the problem of unit crystallization has become an urgent issue to be solved. Utility Model Content

[0003] In order to solve the above problems, the utility model provides an absorption unit adopting a falling film regenerator. The high-temperature regenerator of the absorption unit adopts a falling film heat exchange structure, which effectively improves the heat exchange efficiency between the solution and the steam, reduces the heat exchange loss, and fully recovers the heat of the heat source steam. The low-temperature regenerator adopts a falling film heat exchange structure to reduce the amount of refrigerant water in the heat transfer tube of the low-temperature regenerator, improve the evaporation efficiency of the refrigerant in the high-temperature regenerator, effectively reduce the solution filling amount in the regenerator, and greatly reduce the cost of the unit. High-temperature heat return and low-temperature heat return are used to recover the heat of steam condensation water, thereby realizing efficient recovery of the heat of the heat source steam. An electromagnetic valve for bypassing the intermediate concentration solution and a solution circulation pump for self-circulation of the high-temperature regenerator solution are additionally provided. The liquid level in the high-temperature regenerator is detected in real time by a liquid level detection device, and the start and stop of the dilute solution pump, the solution circulation pump, the electromagnetic valve, and the opening of the steam control valve are controlled. Crystallization will not occur even under the most unfavorable working conditions, thereby improving the safety of the unit.

[0004] The technical solution adopted by the utility model to achieve the above-mentioned purpose is: an absorption unit adopting a falling film regenerator, characterized in that it includes an absorber, an evaporator, a condenser, a low-temperature regenerator, a high-temperature regenerator, a low-temperature heat exchanger, a high-temperature heat exchanger, a refrigerant condensate heat recovery device, a low-temperature heat return, a hydrophobic device, a high-temperature heat return, a dilute solution pump, a concentrated solution pump, and a refrigerant pump, and the high-temperature regenerator and the low-temperature regenerator adopt a solution falling film structure.

[0005] The absorber and evaporator are arranged in a cylinder, the condenser and the low-temperature regenerator are arranged in a cylinder, a dilute solution pump is arranged below the cylinder where the absorber and the evaporator are arranged, a dilute solution pipeline B and a dilute solution pipeline C are arranged in parallel on the dilute solution pipeline A connected to the outlet of the dilute solution pump, a refrigerant condensate heat recovery device, a low-temperature heat return, and a high-temperature heat return are arranged in series in sequence on the dilute solution pipeline B, a low-temperature heat exchanger and a high-temperature heat exchanger are arranged in series in sequence on the dilute solution pipeline C, the ends of the converging pipelines of the dilute solution pipelines B and C are connected to the dilute solution pipeline D, the end of the dilute solution pipeline D is connected to the high-temperature regenerator, and the high-temperature regenerator passes through the intermediate concentration solution Pipeline A is connected to the high-temperature heat exchanger, and the high-temperature heat exchanger is connected to the low-temperature regenerator through the intermediate concentration solution pipeline B. The low-temperature regenerator is connected to the low-temperature heat exchanger through the concentrated solution pipeline A. A concentrated solution pump is arranged on the concentrated solution pipeline A. The low-temperature heat exchanger is connected to the absorber through the concentrated solution pipeline B. The high-temperature regenerator and the low-temperature regenerator are connected through the refrigerant steam pipeline. The low-temperature regenerator is connected to the refrigerant condensate heat recovery device through the refrigerant steam condensate pipeline A. The refrigerant condensate heat recovery device is connected to the condenser through the refrigerant steam condensate pipeline B. A refrigerant pump is arranged on the refrigerant water pipeline B below the absorber and the evaporator cylinder, and the condenser and the evaporator are connected through the refrigerant water pipeline A.

[0006] The evaporator is connected to the cold water inlet pipeline and the cold water outlet pipeline respectively, the condenser is connected to the cooling water inlet pipeline, the absorber is connected to the cooling water outlet pipeline, and the condenser and the absorber are connected through the cooling water pipeline.

[0007] The high-temperature regenerator is connected to the steam inlet pipeline, a steam control valve is arranged on the steam inlet pipeline, the high-temperature regenerator is connected to the high-temperature heat return through the steam condensate pipeline A, the high-temperature heat return and the low-temperature heat return are connected through the steam condensate pipeline B, a drain device is arranged on the steam condensate pipeline B, and the low-temperature heat return is connected to the steam condensate outlet pipeline.

[0008] The dilute solution pump is provided with a frequency converter, and the high-temperature regenerator is provided with a liquid level detection device and a high-temperature sensor.

[0009] An intermediate concentration solution pipeline C is arranged between the intermediate concentration solution pipeline A and the intermediate concentration solution pipeline B, a solenoid valve is arranged on the intermediate concentration solution pipeline C, an intermediate concentration solution bypass pipeline is arranged between the intermediate concentration solution pipeline A and the dilute solution pipeline D, and a solution circulation pump is arranged on the intermediate concentration solution bypass pipeline.

[0010] A one-way valve A is arranged on the dilute solution pipeline D, and a one-way valve B is arranged on the intermediate concentration solution bypass pipeline.

[0011] The high-temperature regenerator and the low-temperature regenerator adopt a steam single-pass or steam multi-pass structure.

[0012] The absorption unit adopts one of the cooling water countercurrent series process, the cooling water forward series process or the cooling water parallel process.

[0013] The beneficial effects of the utility model are:

[0014] 1. The high-temperature regenerator adopts a falling film heat exchange structure, which effectively improves the heat exchange efficiency between the solution and steam, reduces heat exchange losses, and fully recovers the heat of the heat source steam. The low-temperature regenerator adopts a falling film heat exchange structure to reduce the amount of refrigerant water in the heat transfer tube of the low-temperature regenerator, improves the evaporation efficiency of the refrigerant in the high-temperature regenerator, and is beneficial to reducing the heat transfer area of ​​the high-temperature regenerator. It also adopts high-temperature heat return and low-temperature heat return in two stages to recover the heat of steam condensation, thereby realizing efficient recovery of the heat of the heat source steam.

[0015] 2. The high-temperature regenerator and the low-temperature regenerator adopt a solution falling film structure, which effectively reduces the solution filling amount in the regenerator and greatly reduces the unit cost.

[0016] 3. An additional solenoid valve for bypassing the intermediate concentration solution and a solution circulation pump for self-circulation of the high-temperature regenerator solution are installed. The liquid level in the high-temperature regenerator is detected in real time through the liquid level detection device, and the start and stop of the dilute solution pump, solution circulation pump, solenoid valve and the opening of the steam control valve are controlled. Crystallization will not occur even under the most unfavorable operating conditions, thereby improving the safety of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of an absorption unit using a falling film regenerator in the utility model;

[0018] In the figure: 1-absorber, 2-evaporator, 3-condenser, 4-low temperature regenerator, 5-high temperature regenerator, 6-low temperature heat exchanger, 7-high temperature heat exchanger, 8-refrigerant condensate heat recovery device, 9-low temperature heat return, 10-drain device, 11-high temperature heat return, 12-dilute solution pump, 13-concentrated solution pump, 14-refrigerant pump, 15-steam control valve, 16-cooling water inlet pipeline, 17-cooling water outlet pipeline, 18-cooling water pipeline, 19-cold water inlet pipeline, 20-cold water outlet pipeline, 21-steam inlet pipeline, 22-steam condensate outlet pipeline, 23-steam condensate pipeline A, 24-steam condensate pipeline B, 25-dilute solution Pipeline A, 26-dilute solution pipeline B, 27-dilute solution pipeline C, 28-dilute solution pipeline D, 29-intermediate concentration solution pipeline A, 30-intermediate concentration solution pipeline B, 31-intermediate concentration solution pipeline C, 32-intermediate concentration solution bypass pipeline, 33-concentrated solution pipeline A, 34-concentrated solution pipeline B, 35-concentrated solution overflow pipeline, 36-refrigerant steam pipeline, 37-refrigerant steam condensate pipeline A, 38-refrigerant steam condensate pipeline B, 39-refrigerant water pipeline A, 40-refrigerant water pipeline B, 41-solution circulation pump, 42-solvent valve, 43-frequency converter, 44-high re-temperature sensor, 45-liquid level detection device, 46-check valve A, 47-check valve B. DETAILED DESCRIPTION

[0019] The utility model is further described below in conjunction with the accompanying drawings: Example

[0020] like Figure 1 An absorption unit using a falling film regenerator is shown, comprising an absorber 1, an evaporator 2, a condenser 3, a low-temperature regenerator 4, a high-temperature regenerator 5, a low-temperature heat exchanger 6, a high-temperature heat exchanger 7, a refrigerant condensate heat recovery device 8, a low-temperature heat return 9, a hydrophobic device 10, a high-temperature heat return 11, a dilute solution pump 12, a concentrated solution pump 13, and a refrigerant pump 14. The high-temperature regenerator 5 and the low-temperature regenerator 4 adopt a solution falling film structure. The high-temperature regenerator 5 adopts a falling film heat exchange structure, which effectively improves the heat exchange efficiency between the solution and the steam, reduces the heat exchange loss, and fully recovers the heat of the heat source steam. The low-temperature regenerator 4 adopts a falling film heat exchange structure, which reduces the amount of refrigerant water stored in the heat transfer tube of the low-temperature regenerator 4, improves the evaporation efficiency of the refrigerant in the high-temperature regenerator 5, and is beneficial to reducing the heat transfer area of ​​the high-temperature regenerator 5. The falling film heat exchange structure effectively reduces the solution filling amount in the high-temperature regenerator 5 and the low-temperature regenerator 4, and the unit cost is greatly reduced.

[0021] The absorber 1 and the evaporator 2 are arranged in a cylinder, the condenser 3 and the low-temperature regenerator 4 are arranged in a cylinder, a dilute solution pump 12 is arranged below the cylinder where the absorber 1 and the evaporator 2 are arranged, a dilute solution pipeline B26 and a dilute solution pipeline C27 are arranged in parallel on the dilute solution pipeline A25 connected to the outlet of the dilute solution pump 12, a refrigerant condensate heat recovery device 8, a low-temperature heat return 9, and a high-temperature heat return 11 are arranged in series on the dilute solution pipeline B26 in sequence, a low-temperature heat exchanger 6 and a high-temperature heat exchanger 7 are arranged in series on the dilute solution pipeline C27 in sequence, the ends of the converging pipelines of the dilute solution pipelines B26 and C27 are connected to the dilute solution pipeline D28, the end of the dilute solution pipeline D28 is connected to the high-temperature regenerator 5, the high-temperature regenerator 5 is connected to the high-temperature heat exchanger 7 through the intermediate concentration solution pipeline A29, and the high-temperature The heat exchanger 7 is connected to the low-temperature regenerator 4 through the intermediate concentration solution pipeline B30, the low-temperature regenerator 4 is connected to the low-temperature heat exchanger 6 through the concentrated solution pipeline A33, the concentrated solution pipeline A33 is provided with a concentrated solution pump 13, the low-temperature heat exchanger 6 is connected to the absorber 1 through the concentrated solution pipeline B34, the concentrated solution overflow pipeline 35 is connected between the concentrated solution pipeline A33 and the concentrated solution pipeline B34, the high-temperature regenerator 5 and the low-temperature regenerator 4 are connected through the refrigerant steam pipeline 36, the low-temperature regenerator 4 is connected to the refrigerant condensate heat recovery device 8 through the refrigerant steam condensate pipeline A37, and the refrigerant condensate heat recovery device 8 is connected to the condenser 3 through the refrigerant steam condensate pipeline B38; a refrigerant pump 14 is provided on the refrigerant water pipeline B40 below the cylinder of the absorber 1 and the evaporator 2, and the condenser 3 and the evaporator 2 are connected through the refrigerant water pipeline A39. Absorber 1, low-temperature regenerator 4, high-temperature regenerator 5, low-temperature heat exchanger 6, high-temperature heat exchanger 7, refrigerant condensate heat recovery device 8, low-temperature heat return 9, high-temperature heat return 11, dilute solution pump 12, and concentrated solution pump 13 form a solution cycle, that is, the dilute solution from absorber 1 is sent to the dilute solution pipeline A25 through the dilute solution pump 12 and then divided into two paths. One path passes through the dilute solution pipeline B26 and passes through the refrigerant condensate heat recovery device 8, low-temperature heat return 9, and high-temperature heat return 11 in turn. The other path passes through the dilute solution pipeline C27 and passes through the low-temperature heat exchanger 6 and the high-temperature heat exchanger 7 in turn. After the dilute solutions converge, they enter the high-temperature regenerator 5 through the dilute solution pipeline D28 for heating. The intermediate concentration solution is concentrated to form an intermediate concentration solution, which enters the high-temperature heat exchanger 7 through the intermediate concentration solution pipeline A29 to cool down, and then enters the low-temperature regenerator 4 through the intermediate concentration solution pipeline B30, and is heated and concentrated by the refrigerant steam from the high-temperature regenerator 5 through the refrigerant steam pipeline 36 to enter the low-temperature regenerator 4 to form a concentrated solution. The concentrated solution passes through the concentrated solution pump 13 and passes through the low-temperature heat exchanger 6 for heat exchange, and the temperature is reduced. It returns to the absorber 1 through the concentrated solution pipeline B34 and drips on the cooling water pipe, absorbs the refrigerant steam from the evaporator 2, and becomes a dilute solution. At the same time, the refrigerant water drips on the cold water pipe of the evaporator 2 to cool the cold water entering the evaporator 2, thereby realizing refrigeration.

[0022] The evaporator 2 is connected to a cold water inlet pipeline 19 and a cold water outlet pipeline 20 respectively, the condenser 3 is connected to a cooling water inlet pipeline 16, the absorber 1 is connected to a cooling water outlet pipeline 17, and the condenser 3 and the absorber 1 are connected via a cooling water pipeline 18.

[0023] The high-temperature regenerator 5 is connected to the steam inlet pipeline 21, on which a steam control valve 15 is arranged. The high-temperature regenerator 5 is connected to the high-temperature heat return 11 through a steam condensate pipeline A23, and the high-temperature heat return 11 and the low-temperature heat return 9 are connected through a steam condensate pipeline B24. A drain device 10 is arranged on the steam condensate pipeline B24, and the low-temperature heat return 9 is connected to a steam condensate outlet pipeline 22. The heat source steam enters the high-temperature regenerator 5 through the steam inlet pipeline 21 to heat the dilute solution, and the heat source steam enters the high-temperature heat return 11 for primary cooling after being converted into steam condensate. After passing through the drain device 10 for gas-liquid separation, the steam is cooled twice in the low-temperature heat return 9, and finally is discharged from the unit through the steam condensate outlet pipeline 22. The high-temperature heat return 11 and the low-temperature heat return 9 are used to recover the steam condensate heat in two stages, thereby realizing efficient recovery of the heat source steam heat.

[0024] The dilute solution pump 12 is provided with a frequency converter 43, and the high-temperature regenerator 5 is provided with a liquid level detection device 45 and a high re-temperature sensor 44. The frequency conversion and start-stop control of the dilute solution pump 12 are performed based on the comparison between the detection temperature of the high re-temperature sensor 44 and the set temperature of the high-temperature regenerator 5 and the liquid level fed back by the liquid level detection device 45, thereby improving the liquid level stability in the high-temperature regenerator 5. As the detection temperature of the high re-temperature sensor 44 increases, the frequency corresponding to the frequency converter 43 increases accordingly. When the detection temperature of the high re-temperature sensor 44 reaches the set temperature, the frequency converter 43 reaches the maximum frequency.

[0025] An intermediate concentration solution pipeline C31 is arranged between the intermediate concentration solution pipeline A29 and the intermediate concentration solution pipeline B30, and a solenoid valve 42 is arranged on the intermediate concentration solution pipeline C31. An intermediate concentration solution bypass pipeline 32 is arranged between the intermediate concentration solution pipeline A29 and the dilute solution pipeline D28, and a solution circulation pump 41 is arranged on the intermediate concentration solution bypass pipeline 32.

[0026] When the liquid level fed back by the liquid level detection device 45 reaches the first set liquid level, the frequency converter 43 provided on the dilute solution pump 12 runs at a reduced frequency, and the steam control valve 15 is reduced to a 50% opening; when the liquid level fed back by the liquid level detection device 45 reaches the second set liquid level, the dilute solution pump 12 stops running, the solution circulation pump 41 starts running, the steam control valve 15 is closed, the solenoid valve 42 is opened, and the intermediate concentration solution stored in the high temperature regenerator 5 is transported to the low temperature regenerator 4 along the intermediate concentration solution pipeline C31, and the liquid level of the high temperature regenerator 5 decreases accordingly ... When the liquid level drops to the first set liquid level, the dilute solution pump 12 starts running, the solution circulation pump 41 stops running, the steam control valve 15 opens, and the solenoid valve 42 closes. The above control method effectively avoids the liquid level in the high-temperature regenerator 5 from rising and the liquid level in the absorber 1 from falling. The intermediate concentration solution stored in the high-temperature regenerator 5 takes a long time to return. When the heat source steam input is large and the dilute solution pump 12 stops running, crystallization occurs in the falling film high-temperature regenerator 5, the intermediate concentration solution pipeline A29, and the high-temperature heat exchanger 7. Crystallization will not occur in the unit even under the most unfavorable operating conditions, thereby improving the safety of the unit.

[0027] A one-way valve A46 is provided on the dilute solution pipeline D28, and a one-way valve B47 is provided on the intermediate concentration solution bypass pipeline 32, which effectively prevents the solution from flowing in reverse and causing poor solution circulation.

[0028] The high temperature regenerator 5 and the low temperature regenerator 4 are not limited to a single steam flow path, but may also adopt a multi-steam flow path structure.

[0029] The absorption unit is not limited to the cooling water countercurrent series process, but can also adopt the cooling water forward series process or the cooling water parallel process.

[0030] The above-mentioned embodiments are only preferred embodiments of the present invention, but not all feasible embodiments of the present invention. For those skilled in the art, any obvious changes made to the present invention without departing from the principle and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. An absorption unit using a falling film regenerator, characterized in that: The invention comprises an absorber (1), an evaporator (2), a condenser (3), a low-temperature regenerator (4), a high-temperature regenerator (5), a low-temperature heat exchanger (6), a high-temperature heat exchanger (7), a refrigerant condensate heat recovery device (8), a low-temperature heat return (9), a water discharge device (10), a high-temperature heat return (11), a dilute solution pump (12), a concentrated solution pump (13), and a refrigerant pump (14), wherein the high-temperature regenerator (5) and the low-temperature regenerator (4) adopt a solution falling film structure; The absorber (1) and the evaporator (2) are arranged in a cylinder, the condenser (3) and the low-temperature regenerator (4) are arranged in a cylinder, a dilute solution pump (12) is arranged below the cylinder where the absorber (1) and the evaporator (2) are arranged, a dilute solution pipeline B (26) and a dilute solution pipeline C (27) are arranged in parallel on a dilute solution pipeline A (25) connected to the outlet of the dilute solution pump (12), a refrigerant condensate heat recovery device (8), a low-temperature heat return (9), and a high-temperature heat return (11) are arranged in series on the dilute solution pipeline B (26), a low-temperature heat exchanger (6) and a high-temperature heat exchanger (7) are arranged in series on the dilute solution pipeline C (27), the ends of the converging pipelines of the dilute solution pipelines B (26) and C (27) are connected to a dilute solution pipeline D (28), the ends of the dilute solution pipeline D (28) are connected to a high-temperature regenerator (5), and the high-temperature regenerator (5) is connected to the intermediate concentration solution pipeline A (29). The high-temperature heat exchanger (7) is connected to the low-temperature regenerator (4) through an intermediate concentration solution pipeline B (30), the low-temperature regenerator (4) is connected to the low-temperature heat exchanger (6) through a concentrated solution pipeline A (33), a concentrated solution pump (13) is provided on the concentrated solution pipeline A (33), the low-temperature heat exchanger (6) is connected to the absorber (1) through a concentrated solution pipeline B (34), and a refrigerant vapor is provided between the high-temperature regenerator (5) and the low-temperature regenerator (4). The low-temperature regenerator (4) is connected to the refrigerant condensate heat recovery device (8) through the refrigerant steam condensate pipeline A (37), and the refrigerant condensate heat recovery device (8) is connected to the condenser (3) through the refrigerant steam condensate pipeline B (38); a refrigerant pump (14) is provided on the refrigerant water pipeline B (40) below the cylinder of the absorber (1) and the evaporator (2), and the condenser (3) and the evaporator (2) are connected through the refrigerant water pipeline A (39).

2. The absorption unit using a falling film regenerator according to claim 1, characterized in that: The evaporator (2) is connected to a cold water inlet pipeline (19) and a cold water outlet pipeline (20) respectively, the condenser (3) is connected to a cooling water inlet pipeline (16), the absorber (1) is connected to a cooling water outlet pipeline (17), and the condenser (3) and the absorber (1) are connected via a cooling water pipeline (18).

3. The absorption unit using a falling film regenerator according to claim 1, characterized in that: The high-temperature regenerator (5) is connected to a steam inlet pipeline (21), a steam control valve (15) is arranged on the steam inlet pipeline (21), the high-temperature regenerator (5) is connected to the high-temperature heat return (11) via a steam condensate pipeline A (23), the high-temperature heat return (11) and the low-temperature heat return (9) are connected via a steam condensate pipeline B (24), a drain device (10) is arranged on the steam condensate pipeline B (24), and the low-temperature heat return (9) is connected to a steam condensate outlet pipeline (22).

4. The absorption unit using a falling film regenerator according to claim 1, characterized in that: The dilute solution pump (12) is provided with a frequency converter (43), and the high-temperature regenerator (5) is provided with a liquid level detection device (45) and a high-temperature regenerator temperature sensor (44).

5. The absorption unit using a falling film regenerator according to claim 1, characterized in that: An intermediate concentration solution pipeline C (31) is provided between the intermediate concentration solution pipeline A (29) and the intermediate concentration solution pipeline B (30), and a solenoid valve (42) is provided on the intermediate concentration solution pipeline C (31). An intermediate concentration solution bypass pipeline (32) is provided between the intermediate concentration solution pipeline A (29) and the dilute solution pipeline D (28), and a solution circulation pump (41) is provided on the intermediate concentration solution bypass pipeline (32).

6. The absorption unit using a falling film regenerator according to claim 1, characterized in that: A one-way valve A (46) is provided on the dilute solution pipeline D (28), and a one-way valve B (47) is provided on the intermediate concentration solution bypass pipeline (32).

7. An absorption unit using a falling film regenerator according to any one of claims 1 to 6, characterized in that: The high-temperature regenerator (5) and the low-temperature regenerator (4) adopt a steam single-pass or steam multi-pass structure.

8. An absorption unit using a falling film regenerator according to any one of claims 1 to 6, characterized in that: The absorption unit adopts one of the cooling water countercurrent series process, the cooling water forward series process or the cooling water parallel process.

Images