CN212657902U - Evaporative cooling centrifugal water chilling unit - Google Patents
Evaporative cooling centrifugal water chilling unit Download PDFInfo
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- CN212657902U CN212657902U CN202022144776.4U CN202022144776U CN212657902U CN 212657902 U CN212657902 U CN 212657902U CN 202022144776 U CN202022144776 U CN 202022144776U CN 212657902 U CN212657902 U CN 212657902U
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- 238000001816 cooling Methods 0.000 title claims abstract description 34
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title description 16
- 239000007788 liquid Substances 0.000 claims abstract description 29
- 238000004781 supercooling Methods 0.000 claims description 12
- 239000013589 supplement Substances 0.000 claims description 7
- 238000005057 refrigeration Methods 0.000 abstract description 16
- 239000003507 refrigerant Substances 0.000 description 18
- 230000005494 condensation Effects 0.000 description 8
- 238000009833 condensation Methods 0.000 description 8
- 238000001704 evaporation Methods 0.000 description 7
- 230000008020 evaporation Effects 0.000 description 7
- 239000000498 cooling water Substances 0.000 description 6
- 239000013526 supercooled liquid Substances 0.000 description 6
- 230000006835 compression Effects 0.000 description 5
- 238000007906 compression Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 238000004378 air conditioning Methods 0.000 description 4
- 239000002826 coolant Substances 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 230000001502 supplementing effect Effects 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000011552 falling film Substances 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
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Abstract
The utility model discloses an evaporative cooling centrifugal chiller, including evaporimeter, multistage centrifugal compressor, evaporative condenser, the exhaust pipe who links to each other with evaporative condenser and multistage centrifugal compressor respectively, locate check valve, economizer, reservoir, main throttle valve on the exhaust pipe, both ends respectively with the economizer with the high-pressure subcooling pipeline that the main throttle valve links to each other, the side joint is in the auxiliary throttle pipe on the high-pressure subcooling pipeline, locate the auxiliary throttle valve on the auxiliary throttle pipe, the side joint is in the heater bypass pipeline on multistage centrifugal compressor gas vent and check valve, locate heater bypass valve on the heater bypass pipeline, the side joint is in the cooling pipeline on the high-pressure subcooling pipeline; the utility model discloses a configuration economizer and multistage centrifugal compressor middling pressure gas supply pipeline realize the degree of depth subcooling to high-pressure liquid to effectively improve unit refrigeration capacity and refrigeration efficiency.
Description
Technical Field
The utility model belongs to the technical field of refrigeration machinery, especially, relate to a centrifugal cooling water set of evaporation cooling.
Background
In the field of central air conditioning, evaporative cooling is a novel cooling method: meanwhile, circulating water and air are used as cooling media, the liquid-vapor phase change latent heat of the circulating water is mainly utilized to condense high-temperature and high-pressure refrigerant gas into high-temperature liquid, and the heat-transfer-type air-conditioning system has the characteristics of high heat transfer efficiency, low condensing temperature, high refrigeration energy efficiency and the like.
Compared with the traditional water cooling mode, the evaporation cooling unit does not need a cooling tower, a cooling water pump and a special air conditioner room, so that the intermediate heat exchange link of cooling water is reduced, the condensation heat of the refrigerant is directly discharged to air and water, and the condensation temperature of the unit can be effectively reduced so as to improve the refrigeration performance coefficient of the unit. Meanwhile, the unit is provided with a cooling system, and the defects that the linkage between the compressor and the cooling tower and between the compressor and the cooling water pump is poor, the cooling tower and the cooling water pump still run fully when the compressor is unloaded or stopped, so that the running efficiency of the air conditioning system is low and the like are overcome.
Compared with an air cooling mode, the air-cooled condenser overcomes the defects of low heat transfer coefficient, large volume, high condensing temperature, low refrigeration energy efficiency and the like of the traditional air-cooled condenser, and the refrigeration energy efficiency of the unit can be generally improved by about 65 percent compared with the air cooling.
In the refrigeration and air conditioning industry, an evaporative cold screw type water chilling unit is relatively common, but the isentropic efficiency of a screw type refrigeration compressor is 10% -15% lower than that of a centrifugal type refrigeration compressor, so that the refrigeration performance coefficient of the whole machine is relatively low, and the improvement range of the refrigeration energy efficiency is more obvious without the centrifugal compressor when the condensation temperature is reduced.
The Guangdong Shenling environmental system limited company provides an evaporative condensation oil-free water chiller-heater unit and a control method thereof (CN 106440504A), and the conventional centrifugal water chiller unit generally improves the refrigeration energy efficiency by reducing the unit condensation temperature design value or improving the evaporation temperature design value. Because the condenser part of the patent adopts a combination mode of a copper fin type heat exchanger and a serpentine tube heat exchanger, and high-temperature high-pressure gas refrigerant in the copper fin type heat exchanger exchanges heat with high-temperature hot and humid air flowing through the serpentine tube heat exchanger, when the temperature difference between a condensation temperature design value and an inlet air wet bulb temperature is lower than 12 ℃, the copper fin type heat exchanger can be almost only used for precooling an overheated steam section of the high-temperature high-pressure gas refrigerant discharged by a compressor in fact, the heat exchange amount only accounts for about 6-10% of the total condensation heat amount, the effect is limited, but because air resistance exists when air flow passes through the fin type heat exchanger, the power consumption of a fan is increased on the contrary, and the refrigeration energy efficiency of a unit is. Meanwhile, the design of the unit refrigerating system cannot fully utilize the air supplement ports among the impellers of the multistage centrifugal compressor to design an air supplement and enthalpy increase loop so as to carry out deep supercooling design on high-pressure liquid, thereby obviously improving the refrigerating capacity and the refrigerating energy efficiency of the unit.
SUMMERY OF THE UTILITY MODEL
The utility model discloses an overcome prior art not enough, provide a centrifugal cooling water set of evaporation cooling of high refrigerating output and high refrigeration efficiency.
In order to achieve the above purpose, the utility model adopts the following technical scheme: an evaporation cooling centrifugal chiller unit comprises an evaporator, a multistage centrifugal compressor, an air suction pipeline, an evaporative condenser, an exhaust pipeline, a check valve, an economizer and a high-pressure liquid pipeline, wherein the two ends of the air suction pipeline are respectively connected with the evaporator and the multistage centrifugal compressor, the evaporative condenser is connected with the evaporative condenser and the multistage centrifugal compressor, the exhaust pipeline is respectively connected with the evaporative condenser and the multistage centrifugal compressor, the check valve and the economizer are arranged on the exhaust pipeline, the high-pressure liquid pipeline is respectively connected with the evaporative condenser and the economizer, the system comprises a liquid storage device, a main throttle valve, a high-pressure supercooling pipeline, an auxiliary throttle pipe, an auxiliary throttle valve, a heater bypass pipeline, a heater bypass valve and a cooling pipeline, wherein the two ends of the high-pressure supercooling pipeline are respectively connected with an economizer and the main throttle valve; the method is characterized in that: the evaporation cooling centrifugal chiller further comprises an air supplementing pipeline connected with the economizer and the multistage centrifugal compressor; the liquid reservoir is arranged on the high-pressure liquid pipeline; the main throttle valve is also communicated with the evaporator; the outlet of the auxiliary throttle valve is connected to the economizer; the outlet of the bypass valve of the heat exchanger is connected to the evaporator cylinder or the air suction pipeline; one end of the cooling pipeline is communicated with the multistage centrifugal compressor, and high-pressure supercooled liquid is introduced into heating components such as a frequency converter and the like or heating components in the multistage centrifugal compressor so as to cool the heating components. The unit adopts a multi-stage compression technology, a medium-pressure air-supplementing enthalpy-increasing technology and a high-pressure liquid deep supercooling synergistic technology.
Further, the economizer adopts a plate heat exchanger.
The evaporative condenser is different from a conventional air-cooled finned condenser or a water-cooled shell-and-tube condenser, takes air and water as cooling media, mainly utilizes the phase change evaporation of circulating water on the outer surface of a heat exchanger to condense high-temperature and high-pressure refrigerant gas in the heat exchanger into high-pressure liquid, and water vapor is discharged by the air.
The multistage centrifugal compressor can be a magnetic suspension variable-frequency centrifugal compressor, an air suspension variable-frequency centrifugal compressor, a variable-frequency direct-drive centrifugal compressor and a gear speed-increasing centrifugal compressor, and the number of the impellers is two or three. When the number of the impellers is two, low-temperature and low-pressure gas is compressed by the first-stage impeller and then is changed into high-pressure gas, and then enters the suction inlet of the second-stage impeller through the diffuser; when the number of the impellers is three, the exhaust gas of low-temperature and low-pressure gas after the compression pressure of the first-stage impeller is increased enters the suction inlet of the second-stage impeller through the diffuser, the exhaust gas after the compression of the second-stage impeller and the pressure of the exhaust gas after the continuous increase enters the third-stage impeller through the diffuser to be compressed continuously, and the air supplementing port is generally positioned at the suction inlet of the second-stage impeller or the third-stage impeller.
Further, the type of evaporator may be a flooded evaporator, a falling film evaporator, a dry evaporator, or other type of evaporator; the heat exchanger type of the evaporative condenser can be a plate type, a coil type, a plate tube type or other types; the main throttle valve and the auxiliary throttle valve can be of the type of an electronic expansion valve, an electric butterfly valve, an electric ball valve, a thermostatic expansion valve, a fixed or variable orifice plate, or a combination of the above types.
An air supplement pipeline is arranged between the economizer and the air supplement ports of the multistage centrifugal compressor, so that medium-pressure gas at the outlet of the economizer auxiliary pipeline is introduced into the air supplement ports of the multistage centrifugal compressor, and the gas is directly sucked into the suction port of the second-stage or third-stage impeller of the multistage centrifugal compressor for compression.
To sum up, the utility model has the advantages of it is following: the economizer and the medium-pressure gas supplementing pipeline of the multistage centrifugal compressor are configured, so that the high-pressure liquid is deeply supercooled, and the refrigerating capacity and the refrigerating energy efficiency of a unit are effectively improved.
Drawings
Fig. 1 is a schematic diagram of the circuit of the present invention.
Detailed Description
In order to make the technical field personnel understand the utility model discloses the scheme, will combine the drawing in the embodiment of the utility model below, to the technical scheme in the embodiment of the utility model clear, complete description.
As shown in fig. 1, an evaporative cooling centrifugal chiller includes an evaporator 1, a multistage centrifugal compressor 11, a suction line 111, an evaporative condenser 12, an exhaust line 121, a check valve 122, an economizer 2, a high-pressure liquid line 13, a reservoir 131, a main throttle valve 132, a high-pressure subcooling line 133, an auxiliary throttle pipe 141, an auxiliary throttle valve 142, a heater bypass line 123, a heater bypass valve 124, a cooling line 15, and an air make-up line 16; the two ends of a suction pipeline 111 are respectively connected with the evaporator 1 and the multistage centrifugal compressor 11, an exhaust pipeline 121 is respectively connected with the evaporative condenser 12 and the multistage centrifugal compressor 11, a check valve 122 is arranged on the exhaust pipeline 121, a high-pressure liquid pipeline 13 is respectively connected with the evaporative condenser 12 and the economizer 2, two ends of a high-pressure supercooling pipeline 133 are respectively connected with the economizer 2 and the main throttle valve 132, an auxiliary throttle pipe 141 is connected to the high-pressure supercooling pipeline 133 in a bypassing manner, an auxiliary throttle valve 142 is arranged on the auxiliary throttle pipe 141, a heater bypass pipeline 123 is connected to an exhaust port of the multistage centrifugal compressor 11 and the check valve 122 in a bypassing manner, a heater bypass valve 124 is arranged on the heater bypass pipeline 123, a cooling pipeline 15 is connected to the high-pressure supercooling pipeline 133 in a bypassing manner, and an air supplement pipeline 16 is connected with the economizer 2 and the; the reservoir 131 is arranged on the high-pressure liquid pipeline 13; the main throttle valve 132 is also in communication with the evaporator 1; the outlet of the auxiliary throttle valve 142 is connected to the economizer 2; the outlet of the heater bypass valve 124 is connected to the evaporator 1 cylinder or the suction pipeline 111; one end of the cooling pipeline 15 is communicated with the multistage centrifugal compressor; the economizer adopts a plate heat exchanger.
The specific working process is as follows:
the low-temperature and low-pressure gaseous refrigerant from the evaporator 1 enters the multistage centrifugal compressor 11 through the suction line 111, is compressed into a high-temperature and high-pressure gaseous refrigerant by the multistage centrifugal compressor 11, and then enters the evaporative condenser 12 through the check valve 122 and the discharge line 121.
The evaporative condenser 12 is internally provided with a water spraying device and a fan, circulating water is sprayed to the outside of the heat exchanger of the evaporative condenser 12 and exchanges heat with the high-temperature high-pressure gaseous refrigerant in the heat exchanger, a large amount of heat released by the high-temperature high-pressure gaseous refrigerant in the condensation process is absorbed and evaporated into water vapor, the water vapor is discharged into the atmospheric environment by the fan, the high-temperature high-pressure gaseous refrigerant is condensed into high-pressure liquid, and the high-pressure liquid enters the liquid reservoir 131 through the high-pressure liquid pipeline 13 and then enters the economizer 2. In the economizer 2, the refrigerant liquid at medium temperature and medium pressure in the gas exchange plate is cooled into high-pressure supercooled liquid, and then enters the main throttle valve 132 through the high-pressure supercooled pipeline 133 to be expanded, throttled and depressurized into low-temperature and low-pressure gas-liquid refrigerant.
The low-temperature and low-pressure gas-liquid refrigerant coming out of the main throttle valve 132 enters the evaporator 1, exchanges heat with the coolant with relatively high temperature, absorbs the heat of the coolant to cool the coolant, evaporates the coolant into low-temperature and low-pressure gas, is sucked into the multistage centrifugal compressor 11 through the suction pipeline 111, is compressed into high-temperature and high-pressure gaseous refrigerant again, and repeats the operation of the refrigeration cycle.
Part of the high-pressure supercooled liquid enters the auxiliary throttle valve 142 through the branch pipe in the high-pressure supercooling pipeline 133, is throttled and depressurized to medium-temperature medium-pressure gas-liquid refrigerant, then enters the first through hole 23 of the economizer 2, absorbs heat of the high-pressure supercooled liquid on the main side, evaporates to medium-pressure gas, and then exits from the second through hole 24 and enters the medium-pressure cavity of the multistage centrifugal compressor 11 through the gas supplementing pipeline 16.
Meanwhile, a small amount of high-pressure supercooled liquid is introduced into the multistage centrifugal compressor 11 from the cooling line 15 introduced from the high-pressure supercooled line 133, and is phase-changed into a gas-liquid mixed refrigerant of medium temperature, medium pressure, or low temperature, low pressure (depending on the internal structural design of the compressor) by an internal flow control valve member to cool the compressor motor, or the high-pressure supercooled liquid is used to cool heat generating components such as a frequency converter.
In the operation process, when the rotating speed of the multistage centrifugal compressor 11 is too low or the pressure ratio is too high, the hot gas bypass valve is opened, and the high-temperature and high-pressure gaseous refrigerant discharged by the multistage centrifugal compressor 11 is discharged into the evaporator 1 with lower pressure through the hot gas bypass pipeline, so that the abnormal conditions of surge and the like of the compressor are avoided.
Because the design of the refrigerating system adopts the multi-stage compression and air-supplying enthalpy-increasing technology, the economizer 2 and the medium-pressure air supply of the multi-stage centrifugal compressor 11 can realize deep supercooling of high-pressure liquid in front of the main throttle valve 132, and reduce the dryness and enthalpy values of low-temperature and low-pressure gas-liquid refrigerant entering the evaporator 1, thereby effectively improving the refrigerating capacity and the refrigerating energy efficiency of the unit.
The basic principles and the main features of the invention and the advantages of the invention have been shown and described above, it will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, but that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (5)
1. An evaporative cooling centrifugal chiller characterized by: the system comprises an evaporator (1), a multi-stage centrifugal compressor (11), a suction pipeline (111) with two ends respectively connected with the evaporator (1) and the multi-stage centrifugal compressor (11), an evaporative condenser (12), a gas exhaust pipeline (121) respectively connected with the evaporative condenser (12) and the multi-stage centrifugal compressor (11), a check valve (122) arranged on the gas exhaust pipeline (121), an economizer (2), a high-pressure liquid pipeline (13) respectively connected with the evaporative condenser (12) and the economizer (2), a liquid storage device (131), a main throttle valve (132), a high-pressure supercooling pipeline (133) with two ends respectively connected with the economizer (2) and the main throttle valve (132), an auxiliary throttle pipe (141) connected to the high-pressure supercooling pipeline (133) in a bypassing manner, and an auxiliary throttle valve (142) arranged on the auxiliary throttle pipe (141), A heater bypass pipeline (123) which is connected with the exhaust port and the check valve (122) of the multistage centrifugal compressor (11) in a bypassing way, a heater bypass valve (124) which is arranged on the heater bypass pipeline (123), a cooling pipeline (15) which is connected with the high-pressure supercooling pipeline (133) in a bypassing way, and an air supplement pipeline (16) which is connected with the economizer (2) and the multistage centrifugal compressor.
2. An evaporative cooling centrifugal chiller as set forth in claim 1 wherein: the liquid storage device (131) is arranged on a high-pressure liquid pipeline (13), and the main throttle valve (132) is communicated with the evaporator (1).
3. An evaporative cooling centrifugal chiller as set forth in claim 1 wherein: the outlet of the auxiliary throttle valve (142) is connected to the economizer (2); the outlet of the heat exchanger bypass valve (124) is connected to the barrel of the evaporator (1) or the air suction pipeline (111).
4. An evaporative cooling centrifugal chiller as set forth in claim 1 wherein: one end of the cooling pipeline (15) is communicated with the multistage centrifugal compressor.
5. An evaporative cooling centrifugal chiller as set forth in claim 1 wherein: the economizer (2) adopts a plate heat exchanger.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022144776.4U CN212657902U (en) | 2020-09-25 | 2020-09-25 | Evaporative cooling centrifugal water chilling unit |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202022144776.4U CN212657902U (en) | 2020-09-25 | 2020-09-25 | Evaporative cooling centrifugal water chilling unit |
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| CN212657902U true CN212657902U (en) | 2021-03-05 |
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| CN202022144776.4U Active CN212657902U (en) | 2020-09-25 | 2020-09-25 | Evaporative cooling centrifugal water chilling unit |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112050490A (en) * | 2020-09-25 | 2020-12-08 | 浙江国祥股份有限公司 | An evaporative cooling centrifugal chiller |
| CN116007214A (en) * | 2022-12-15 | 2023-04-25 | 华涧新能源科技(上海)有限公司 | Energy storage heat management system of centrifugal compressor |
| CN118482488A (en) * | 2024-05-20 | 2024-08-13 | 中国船舶集团有限公司第七一一研究所 | Liquid ammonia supercooling and propylene cold insulation coupling refrigerating system |
-
2020
- 2020-09-25 CN CN202022144776.4U patent/CN212657902U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112050490A (en) * | 2020-09-25 | 2020-12-08 | 浙江国祥股份有限公司 | An evaporative cooling centrifugal chiller |
| CN116007214A (en) * | 2022-12-15 | 2023-04-25 | 华涧新能源科技(上海)有限公司 | Energy storage heat management system of centrifugal compressor |
| CN118482488A (en) * | 2024-05-20 | 2024-08-13 | 中国船舶集团有限公司第七一一研究所 | Liquid ammonia supercooling and propylene cold insulation coupling refrigerating system |
| CN118482488B (en) * | 2024-05-20 | 2025-12-30 | 中国船舶集团有限公司第七一一研究所 | A coupled refrigeration system of liquid ammonia subcooling and propylene insulation |
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