Air separation precooling system

Abstract

The utility model discloses an air separation precooling system which comprises a water cooling tower, an air cooling tower and a normal-temperature cooling water pump, the normal-temperature cooling water pump is communicated to the middle of the air cooling tower through a normal-temperature cooling water pipeline, and a liquid outlet in the bottom of the water cooling tower is communicated to the middle upper portion of the air cooling tower through a pipeline. An air cooling tower drainage pipeline of the air cooling tower is communicated with two air cooling tower drainage regulating valve bypass pipelines, and the two air cooling tower drainage regulating valve bypass pipelines are both connected to the mixed-flow water turbine; the mixed-flow water turbine is coaxially connected with the normal-temperature cooling water pump, and the asynchronous motor is further coaxially arranged between the mixed-flow water turbine and the normal-temperature cooling water pump. Static pressure energy at the drainage regulating valve of the air cooling tower is used for driving the normal-temperature water pump, the asynchronous motor is used for reversely generating power for other equipment of the air separation system, and electric energy consumption of the air separation system is reduced.

Description

TECHNICAL FIELD

[0001] The utility model belongs to air separation technical field, and specifically relates to air separation precooling system. BACKGROUND

[0002] Air separation precooling system is an important component in air separation system, and is used for cooling the hot air after compression in air cooling tower by cooling water, wherein the cooling water in the air cooling tower is from external cooling circulating water and refrigerated water after cooling in water cooling tower.

[0003] Air separation precooling system is mainly composed of air cooling tower, water cooling tower, refrigerated water pump, normal temperature water pump and regulating valve. Process flow is as follows: hot air after compression enters lower part of air cooling tower, passes through mass transfer unit in the air cooling tower from bottom to top, and sequentially contacts with lower normal temperature cooling water and upper low temperature refrigerated water in counter flow to carry out heat transfer and mass transfer, so as to achieve the purpose of cooling air and removing most of water-soluble harmful substances. Normal temperature cooling water is supplied by external circulating water system, and enters middle part of air cooling tower after being pressurized by normal temperature water pump; low temperature refrigerated water is supplied by external circulating water system, and enters upper part of air cooling tower after being pressurized by refrigerated water pump, after being cooled by polluted nitrogen in water cooling tower. Low temperature refrigerated water and normal temperature cooling water are discharged from bottom to external circulating water return pipe after heat exchange in air cooling tower.

[0004] Generally, pressure in the air cooling tower is high, that is, the cooling water discharged from the air cooling tower has high pressure, and the pressure of external circulating cooling water return pipe is low, so a regulating valve is arranged on the air cooling tower drainage pipe. In order to maintain stable pressure in the air cooling tower, it is necessary to maintain stable water level in the tower, so the opening of the air cooling tower drainage regulating valve is generally small, which results in great waste of static pressure energy before and after the air cooling tower drainage regulating valve. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing air separation precooling system, using static pressure energy at the air cooling tower drainage regulating valve to drive normal temperature water pump, and using reverse power generation of asynchronous motor to supply other devices in air separation system, so as to reduce power consumption of air separation system.

[0006] The utility model adopts the technical scheme that air separation precooling system, including water cooling tower, the top of water cooling tower is connected with outside circulating cooling water supply pipeline, outside circulating cooling water supply pipeline is connected with normal temperature cooling water pump still, normal temperature cooling water pump is communicated to air cooling tower middle part through normal temperature cooling water pipeline, the bottom liquid outlet of water cooling tower is communicated to air cooling tower middle upper part through pipeline, air cooling tower drainage pipeline of air cooling tower is connected with air cooling tower drainage regulating valve bypass pipeline, the other end of air cooling tower drainage regulating valve bypass pipeline is connected with mixed flow water turbine, the outlet end of mixed flow water turbine is connected with another air cooling tower drainage regulating valve bypass pipeline, and one end of another air cooling tower drainage regulating valve bypass pipeline is connected with outside circulating cooling water return pipeline.

[0007] The mixed-flow water turbine is coaxially connected with the normal-temperature cooling water pump, and an asynchronous motor is coaxially arranged between the mixed-flow water turbine and the normal-temperature cooling water pump.

[0008] The utility model discloses further characterized by,

[0009] The normal-temperature cooling water pump is connected with the asynchronous motor through a shaft coupling.

[0010] An overrunning clutch is arranged between the asynchronous motor and the mixed-flow water turbine, and the mixed-flow water turbine is connected with the asynchronous motor through the overrunning clutch.

[0011] A water turbine inlet electric regulating valve is arranged on a bypass pipeline of an air cooling tower drainage regulating valve connected with an inlet of the mixed-flow water turbine; and a water turbine outlet electric regulating valve is arranged on a bypass pipeline of an air cooling tower drainage regulating valve connected with an outlet of the mixed-flow water turbine.

[0012] One end of the air cooling tower drainage pipeline is provided with an air cooling tower drainage regulating valve, and the other end of the air cooling tower drainage regulating valve is connected with an external circulating cooling water return pipeline.

[0013] The top of the air cooling tower is provided with a cold air outlet pipeline.

[0014] The bottom liquid outlet of the water cooling tower is connected to a chilled water pump through a pipeline, and the chilled water pump is connected to the upper part of the air cooling tower through a chilled water pipeline.

[0015] A hot air pipeline is arranged on one side of the air cooling tower above the liquid level of the air cooling tower, and the inside of the hot air pipeline is compressed hot air.

[0016] The utility model has the advantages of:

[0017] The air separation precooling system of the utility model sets an asynchronous motor on one side of the normal-temperature cooling water pump, sets a mixed-flow water turbine on one side of the asynchronous motor, coaxially sets the mixed-flow water turbine, the asynchronous motor and the normal-temperature cooling water pump, recycles the static pressure energy loss at the air cooling tower drainage regulating valve by using the water turbine, drags the normal operation of the normal-temperature cooling water pump, reversely generates electricity by using the asynchronous motor to supply other electric equipment in the system, thereby reducing the electric energy consumption of the air separation system. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is the structure schematic diagram of the air separation precooling system of the utility model.

[0019] In the figure, 1. Water-cooling tower, 2. Air-cooling tower, 3. External circulating cooling water supply pipeline, 4. Chilled water pump, 5. Chilled water pipeline, 6. Normal temperature cooling water pump, 7. Asynchronous motor, 8. Normal temperature cooling water pipeline, 9. Air-cooling tower drain regulating valve, 10. Hot air pipeline, 11. Cold air outlet pipeline, 12. Air-cooling tower liquid level, 13. Francis turbine, 14. Overrunning clutch, 15. Turbine inlet electric regulating valve, 16. Turbine outlet manual valve, 17. Air-cooling tower drain pipeline, 18. External circulating cooling water return pipeline, 19. Air-cooling tower drain regulating valve bypass pipeline. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] Example 1

[0022] The utility model air separation precooling system, such as Figure 1 As shown, it includes a water-cooling tower 1, the top of the water-cooling tower 1 is connected to an external circulating cooling water supply pipe 3, the external circulating cooling water supply pipe 3 is also connected to a normal temperature cooling water pump 6, the normal temperature cooling water pump 6 is connected to the middle of the air-cooling tower 2 through the normal temperature cooling water pipe 8, the bottom liquid outlet of the water-cooling tower 1 is connected to the upper and middle part of the air-cooling tower 2 through a pipe, the air-cooling tower drainage pipe 17 of the air-cooling tower 2 is connected to an air-cooling tower drainage regulating valve bypass pipe 19, the other end of the air-cooling tower drainage regulating valve bypass pipe 19 is connected to a Francis turbine 13, the outlet end of the Francis turbine 13 is connected to another air-cooling tower drainage regulating valve bypass pipe 19, one end of the other air-cooling tower drainage regulating valve bypass pipe 19 is connected to the external circulating cooling water return pipe 18, that is, the water flow in the air-cooling tower drainage pipe 17 passes through the Francis turbine 13 and then returns to the external circulating cooling water return pipe 18;

[0023] The Francis turbine 13 is coaxially connected to the normal temperature cooling water pump 6 , and an asynchronous motor 7 is coaxially arranged between the Francis turbine 13 and the normal temperature cooling water pump 6 .

[0024] That is, this solution connects an air-cooling tower drainage regulating valve bypass pipe 19 to one side of the air-cooling tower drainage pipe 17, thereby guiding the water resources that were originally directly returned to the position of the Francis turbine 13, and then the Francis turbine 13 drives the normal temperature cooling water pump 6 and the asynchronous motor 7 to operate. The electric energy generated and stored by the asynchronous motor 7 is used for consumption by other electrical equipment in the system, thereby reducing the consumption of existing resources by this system.

[0025] Embodiment 2

[0026] The utility model discloses air separation precooling system, as shown in Figure 1 The utility model discloses air separation precooling system, as shown in

[0027] The mixed flow water turbine 13 is coaxial with the normal temperature cooling water pump 6, and an asynchronous motor 7 is coaxially arranged between the mixed flow water turbine 13 and the normal temperature cooling water pump 6.

[0028] Further, the normal temperature cooling water pump 6 is connected with the asynchronous motor 7 through a shaft coupling.

[0029] Further, a one-way clutch 14 is arranged between the asynchronous motor 7 and the mixed flow water turbine 13, and the mixed flow water turbine 13 is connected with the asynchronous motor 7 through the one-way clutch 14.

[0030] The one-way clutch 14 is a kind of one-way clutch, it allows power transmission to rotate freely in one direction, and in opposite direction, then lock and transmit torque.When the rotational speed of driving shaft is higher than driven shaft, clutch is in engagement state, and power is transmitted from driving shaft to driven shaft;When the rotational speed of driving shaft is lower than or equal to driven shaft, clutch is in separation state, and driven shaft can continue to rotate at its own speed, without being limited by driving shaft.

[0031] Embodiment 3

[0032] The utility model discloses air separation precooling system, as shown in Figure 1As shown, it includes a water-cooling tower 1, the top of the water-cooling tower 1 is connected to an external circulating cooling water supply pipe 3, the external circulating cooling water supply pipe 3 is also connected to a normal temperature cooling water pump 6, the normal temperature cooling water pump 6 is connected to the middle of the air-cooling tower 2 through the normal temperature cooling water pipe 8, the bottom liquid outlet of the water-cooling tower 1 is connected to the upper and middle part of the air-cooling tower 2 through a pipe, the air-cooling tower drainage pipe 17 of the air-cooling tower 2 is connected to an air-cooling tower drainage regulating valve bypass pipe 19, the other end of the air-cooling tower drainage regulating valve bypass pipe 19 is connected to a Francis turbine 13, the outlet end of the Francis turbine 13 is connected to another air-cooling tower drainage regulating valve bypass pipe 19, one end of the other air-cooling tower drainage regulating valve bypass pipe 19 is connected to the external circulating cooling water return pipe 18, that is, the water flow in the air-cooling tower drainage pipe 17 passes through the Francis turbine 13 and then returns to the external circulating cooling water return pipe 18;

[0033] The Francis turbine 13 is coaxially connected to the normal temperature cooling water pump 6 , and an asynchronous motor 7 is coaxially arranged between the Francis turbine 13 and the normal temperature cooling water pump 6 .

[0034] Furthermore, the normal temperature cooling water pump 6 is connected to the asynchronous motor 7 via a coupling.

[0035] Furthermore, an overrunning clutch 14 is provided between the asynchronous motor 7 and the Francis turbine 13 , and the Francis turbine 13 and the asynchronous motor 7 are connected via the overrunning clutch 14 .

[0036] Furthermore, a turbine inlet electric regulating valve 15 is provided on the air-cooling tower drainage regulating valve bypass pipe 19 connected to the inlet of the mixed flow turbine 13; a turbine outlet electric regulating valve 16 is provided on the air-cooling tower drainage regulating valve bypass pipe 19 connected to the outlet of the mixed flow turbine 13.

[0037] The asynchronous motor 7, also known as an induction motor, is an AC motor that converts electrical energy into mechanical energy. A normally operating asynchronous motor converts electrical energy into mechanical energy. However, when the asynchronous motor's rotor is driven by a prime mover (such as a steam turbine or water turbine) and the rotor speed exceeds the synchronous speed, it enters a power generation state. The present utility model utilizes this characteristic of the asynchronous motor 7 to serve as a supplemental energy source for the normal-temperature cooling water pump 6 when the Francis turbine 13 is underpowered. Furthermore, when the Francis turbine 13's output power exceeds the input power required by the normal-temperature cooling water pump 6, the excess power can be converted into electrical energy for storage.

[0038] Example 4

[0039] The utility model air separation precooling system, including water cooling tower 1, water cooling tower 1's top is connected with outside circulating cooling water water supply pipeline 3, outside circulating cooling water water supply pipeline 3 still is connected with normal temperature cooling water pump 6, normal temperature cooling water pump 6 is connected to the middle part of air cooling tower 2 through normal temperature cooling water pipeline 8, and the bottom liquid outlet of water cooling tower 1 is connected to the middle upper part of air cooling tower 2 through pipeline, and the air cooling tower drainage pipeline 17 of air cooling tower 2 is connected with one air cooling tower drainage regulating valve bypass pipeline 19, and the other end of air cooling tower drainage regulating valve bypass pipeline 19 is connected with the mixed flow water turbine 13, and the outlet end of mixed flow water turbine 13 is connected with another air cooling tower drainage regulating valve bypass pipeline 19, and one end of another air cooling tower drainage regulating valve bypass pipeline 19 is connected with external circulating cooling water return pipeline 18, that is, the water flow in air cooling tower drainage pipeline 17 returns to external circulating cooling water return pipeline 18 after passing through mixed flow water turbine 13;

[0040] Mixed flow water turbine 13 is coaxially connected with normal temperature cooling water pump 6, and asynchronous motor 7 is coaxially arranged between mixed flow water turbine 13 and normal temperature cooling water pump 6.

[0041] Further, water turbine inlet electric regulating valve 15 is arranged on air cooling tower drainage regulating valve bypass pipeline 19 connected with the inlet of mixed flow water turbine 13, and water turbine outlet electric regulating valve 16 is arranged on air cooling tower drainage regulating valve bypass pipeline 19 connected with the outlet of mixed flow water turbine 13.

[0042] Further, air cooling tower drainage regulating valve 9 is arranged at one end of air cooling tower drainage pipeline 17, and the other end of air cooling tower drainage regulating valve 9 is connected with external circulating cooling water return pipeline 18.

[0043] Embodiment 5

[0044] The utility model air separation precooling system, including water cooling tower 1, water cooling tower 1's top is connected with outside circulating cooling water water supply pipeline 3, outside circulating cooling water water supply pipeline 3 still is connected with normal temperature cooling water pump 6, normal temperature cooling water pump 6 is connected to the middle part of air cooling tower 2 through normal temperature cooling water pipeline 8, and the bottom liquid outlet of water cooling tower 1 is connected to the middle upper part of air cooling tower 2 through pipeline, and the air cooling tower drainage pipeline 17 of air cooling tower 2 is connected with one air cooling tower drainage regulating valve bypass pipeline 19, and the other end of air cooling tower drainage regulating valve bypass pipeline 19 is connected with the mixed flow water turbine 13, and the outlet end of mixed flow water turbine 13 is connected with another air cooling tower drainage regulating valve bypass pipeline 19, and one end of another air cooling tower drainage regulating valve bypass pipeline 19 is connected with external circulating cooling water return pipeline 18, that is, the water flow in air cooling tower drainage pipeline 17 returns to external circulating cooling water return pipeline 18 after passing through mixed flow water turbine 13;

[0045] The mixed-flow water turbine 13 is coaxially connected with the normal-temperature cooling water pump 6, and an asynchronous motor 7 is coaxially arranged between the mixed-flow water turbine 13 and the normal-temperature cooling water pump 6.

[0046] Further, the top of the air cooling tower 2 is provided with a cold air outlet pipeline 11.

[0047] Further, the bottom liquid outlet of the water cooling tower 1 is connected to the chilled water pump 4 through a pipeline, and the chilled water pump 4 is connected to the middle upper part of the air cooling tower 2 through a chilled water pipeline 5.

[0048] Embodiment 6

[0049] The air separation precooling system of the utility model, including water cooling tower 1, water cooling tower 1's top is connected with outside circulating cooling water supply pipeline 3, outside circulating cooling water supply pipeline 3 still is connected with normal-temperature cooling water pump 6, normal-temperature cooling water pump 6 is connected to air cooling tower 2 middle part through normal-temperature cooling water pipeline 8, water cooling tower 1's bottom liquid outlet is connected to air cooling tower 2 middle upper part through pipeline, air cooling tower 2's air cooling tower drainage pipeline 17 is connected with a air cooling tower drainage regulating valve bypass pipeline 19, air cooling tower drainage regulating valve bypass pipeline 19's other end is connected with mixed-flow water turbine 13, mixed-flow water turbine 13's export end is connected with another air cooling tower drainage regulating valve bypass pipeline 19, another air cooling tower drainage regulating valve bypass pipeline 19's one end is connected with outside circulating cooling water return pipeline 18, namely the water flow in air cooling tower drainage pipeline 17 is returned to outside circulating cooling water return pipeline 18 after passing through mixed-flow water turbine 13;

[0050] The mixed-flow water turbine 13 is coaxially connected with the normal-temperature cooling water pump 6, and an asynchronous motor 7 is coaxially arranged between the mixed-flow water turbine 13 and the normal-temperature cooling water pump 6.

[0051] Further, the top of the air cooling tower 2 is provided with a cold air outlet pipeline 11.

[0052] Further, the bottom liquid outlet of the water cooling tower 1 is connected to the chilled water pump 4 through a pipeline, and the chilled water pump 4 is connected to the middle upper part of the air cooling tower 2 through a chilled water pipeline 5.

[0053] Further, the air cooling tower 2 is provided with a hot air pipeline 10 on one side above the air cooling tower liquid level 12, and the inside of the hot air pipeline 10 is compressed hot air.

[0054] The working principle of the air separation precooling system of the utility model is as follows:

[0055] The drainage of the air cooling tower 2 enters the mixed flow water turbine 13 through a set of air cooling tower drainage regulating valve bypass pipelines 19, the water turbine converts the static pressure energy of the air cooling tower drainage into kinetic energy, and outputs to the asynchronous motor 7 and the normal temperature cooling water pump 6 through the overrunning clutch 14, drags the normal temperature cooling water pump 6 and the asynchronous motor 7, and uses the asynchronous motor 7 to generate electricity in reverse to supply other devices of the air separation system, and reduces the power consumption of the air separation system.

[0056] In normal operation, the water turbine inlet electric regulating valve 15 is opened, the air cooling tower drainage regulating valve 9 is closed in linkage, the rotating speed of the mixed flow water turbine 13 is increased, when the rotating speed of the water turbine 13 is higher than that of the asynchronous motor 7, the overrunning clutch 14 is automatically coupled, the mixed flow water turbine 13 drags the normal temperature cooling water pump 6 and the asynchronous motor 7 to operate, and uses the asynchronous motor 7 to generate electricity in reverse.

[0057] The water inflow of the mixed flow water turbine 13 is adjusted according to the opening of the water turbine inlet electric regulating valve 15 controlled by the air cooling tower liquid level 12, so as to maintain the stability of the air cooling tower liquid level 12, and thus maintain the stability of the air cooling tower 2.

[0058] When the air cooling tower drainage amount is just equal to the operating power of the normal temperature cooling water pump 6, the asynchronous motor 7 is operated in no-load, and the mixed flow water turbine 13 drags the normal temperature cooling water pump 6 to operate alone.

[0059] When the air cooling tower drainage amount is reduced, the output power of the mixed flow water turbine 13 is less than the operating power of the normal temperature cooling water pump 6, the mixed flow water turbine 13 and the asynchronous motor 7 jointly drag the normal temperature cooling water pump 6 to operate.

[0060] When the air cooling tower drainage amount is increased, the output power of the mixed flow water turbine 13 is greater than the operating power of the normal temperature cooling water pump 6, the rotating speed of the mixed flow water turbine 13 is increased, when the rotating speed is greater than the synchronous rotating speed of the dragged asynchronous motor 7, the asynchronous motor 7 changes from a motor to a generator, that is, the water turbine drags the normal temperature cooling water pump 6 to operate normally, and also drags the asynchronous motor 7 to generate electricity in reverse.

[0061] When the mixed flow water turbine 13 fails, the water turbine inlet electric regulating valve 15 is closed in linkage, the air cooling tower drainage regulating valve 9 is opened in linkage, the rotating speed of the mixed flow water turbine 13 is reduced, and the overrunning clutch 14 is automatically separated, so as to restore to the original system operation.

[0062] Finally, it should be noted that, in the description above, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the presence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0063] The various embodiments in the specification are described with progression in this fashion. The description is not an exhaustive list of every possible embodiment. Merely referencing the inclusion of one feature in a body of work does not necessarily foreclose the presence of another feature that is not explicitly described or even contemporaneously described. This description is not meant to be all-inclusive or limited to the embodiments described.

[0064] The above description of disclosed embodiments is intended to be illustrative, and not restrictive. Many embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the application should, therefore, be determined not with reference to the above description, but instead with reference to the appended claims, along with their full scope of equivalents.

Claims

1. An air separation precooling system, comprising a water cooling tower (1), wherein the top of the water cooling tower (1) is connected to an external circulating cooling water supply pipe (3), the external circulating cooling water supply pipe (3) is further connected to a normal temperature cooling water pump (6), the normal temperature cooling water pump (6) is connected to the middle of an air cooling tower (2) through a normal temperature cooling water pipe (8), and the bottom liquid outlet of the water cooling tower (1) is connected to the upper middle part of the air cooling tower (2) through a pipe, characterized in that: The air-cooling tower drainage pipe (17) of the air-cooling tower (2) is connected to an air-cooling tower drainage regulating valve bypass pipe (19), the other end of the air-cooling tower drainage regulating valve bypass pipe (19) is connected to the Francis turbine (13), the outlet end of the Francis turbine (13) is connected to another air-cooling tower drainage regulating valve bypass pipe (19), and one end of the other air-cooling tower drainage regulating valve bypass pipe (19) is connected to the external circulating cooling water return pipe (18); The Francis turbine (13) is coaxially connected to the normal temperature cooling water pump (6), and an asynchronous motor (7) is coaxially arranged between the Francis turbine (13) and the normal temperature cooling water pump (6).

2. The air separation precooling system according to claim 1, characterized in that: The normal temperature cooling water pump (6) is connected to the asynchronous motor (7) via a coupling.

3. The air separation precooling system according to claim 1, characterized in that: An overrunning clutch (14) is provided between the asynchronous motor (7) and the Francis turbine (13), and the Francis turbine (13) and the asynchronous motor (7) are connected via the overrunning clutch (14).

4. The air separation precooling system according to claim 1, characterized in that: A turbine inlet electric regulating valve (15) is provided on an air-cooling tower drainage regulating valve bypass pipe (19) connected to the inlet of the Francis turbine (13); and a turbine outlet electric regulating valve (16) is provided on an air-cooling tower drainage regulating valve bypass pipe (19) connected to the outlet of the Francis turbine (13).

5. The air separation precooling system according to claim 1, characterized in that: An air cooling tower drainage regulating valve (9) is provided at one end of the air cooling tower drainage pipe (17), and the other end of the air cooling tower drainage regulating valve (9) is connected to the external circulating cooling water return pipe (18).

6. The air separation precooling system according to claim 1, characterized in that: A cold air outlet pipe (11) is provided at the top of the air cooling tower (2).

7. The air separation precooling system according to claim 1, characterized in that: The bottom liquid outlet of the water cooling tower (1) is connected to a chilled water pump (4) through a pipeline, and the chilled water pump (4) is connected to the upper middle portion of the air cooling tower (2) through a chilled water pipeline (5).

8. The air separation precooling system according to claim 1, characterized in that: A hot air pipe (10) is provided on one side of the air cooling tower (2) above the air cooling tower liquid level (12), and the interior of the hot air pipe (10) is compressed hot air.

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