Anti-surge refrigerating unit assembly
By using a combination of anti-surge cooler and anti-surge valve in the refrigeration unit, the surge problem of centrifugal compressors was solved, and the long-term stable operation and safety and reliability of the refrigeration unit were achieved.
Patent Information
- Application Number
- CN202520335119.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-28
- Publication Date
- 2026-02-24
- Estimated Expiration
- 2035-02-28
AI Technical Summary
Centrifugal compressors in refrigeration units are prone to surge, which can lead to unstable operation of the unit or even damage to the compressor. Existing methods have hidden dangers and poor stability.
A combination of anti-surge cooler and anti-surge valve is adopted to prevent liquefaction by cooling the gaseous refrigerant to above the saturation temperature, and to eliminate the refrigerant injector and use a static cooler to ensure stability.
It effectively prevents surge, ensures long-term stable operation of the refrigeration unit, avoids tripping caused by excessively high liquid level or temperature in the inlet separator, and improves safety and reliability.
Smart Images
Figure CN223939669U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of refrigeration unit technology, specifically relating to an anti-surge refrigeration unit assembly. Background Technology
[0002] Refrigeration units, such as ammonia compressors and propylene compressors, are core equipment in refrigeration systems, and their stable operation is crucial for the long-term operation of the entire unit. Centrifugal compressors are a common type of refrigeration unit, characterized by their small size, high efficiency, and relatively stable operation. However, they are inherently prone to surge, which is highly dangerous, affecting the normal operation of the unit and even damaging the compressor. The root cause of surge is insufficient gas flow, with the compressor inlet gas volume lower than the required surge flow. To increase the compressor inlet flow, one method is to install a bypass line to return some of the gas from the compressor outlet to the compressor inlet, thus preventing surge. In practice, this method has certain risks. To prevent the compressor from overheating due to inlet temperature, cooling measures need to be implemented in the surge circuit. Common processes include an aftercooler + ejector process or a separate ejector process. During low-load start-up or ejector failure, this can cause high liquid levels or temperatures in the inlet separators of various sections of the refrigeration unit, leading to tripping, poor stability, and in severe cases, damage to the refrigeration unit. Summary of the Invention
[0003] The purpose of this utility model is to solve the above-mentioned technical problems and provide an anti-surge refrigeration unit assembly that effectively ensures the normal operation of the compressor.
[0004] To achieve the above objectives, this utility model provides an anti-surge refrigeration unit assembly, including an inlet separator, a refrigeration unit, an anti-surge cooler, an outlet condenser, a receiving tank, and an anti-surge valve. The outlet of the inlet separator is connected to the inlet of the refrigeration unit. One gas outlet of the refrigeration unit is connected to the inlet of the receiving tank via the outlet condenser. The venting gas from the receiving tank is discharged from the top of the receiving tank, and the refrigerant flows out from the bottom of the receiving tank to the refrigerant user. The other gas outlet of the refrigeration unit is connected to the inlet of the inlet separator via the anti-surge valve and the anti-surge cooler in sequence.
[0005] Furthermore, there are two inlet separators, and correspondingly, there are two anti-surge coolers and two anti-surge valves, namely, a first-stage inlet separator, a second-stage inlet separator, an anti-surge valve #1, an anti-surge valve #2, an anti-surge cooler #1, and an anti-surge cooler #2. The first-stage inlet separator corresponds to the anti-surge valve #1 and the anti-surge cooler #1, and the second-stage inlet separator corresponds to the anti-surge valve #2 and the anti-surge cooler #2.
[0006] Furthermore, the anti-surge cooler operates at a low pressure of 0.2–0.5 MPaG.
[0007] Furthermore, the circulating cooling water temperature of the anti-surge cooler is 28–33°C.
[0008] Compared with the prior art, the beneficial effects of this utility model are as follows: the anti-surge valve of this utility model is connected to an anti-surge cooler to cool the gaseous refrigerant to the required temperature. The cooling temperature is higher than the saturation temperature of the refrigerant under the operating pressure, so it will not liquefy. At the same time, there is no need to set up a refrigerant injector in the process. Compared with the refrigerant injector, the cooler is a static device with good stability. It essentially avoids the occurrence of tripping, is safe and reliable, has a simple process, and the refrigeration unit can operate stably for a long time. Attached Figure Description
[0009] Figure 1 This is a schematic diagram of the anti-surge refrigeration unit assembly of this utility model. Detailed Implementation
[0010] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0011] like Figure 1 The anti-surge refrigeration unit assembly shown includes an inlet separator, a refrigeration unit 3, an anti-surge cooler, an outlet condenser 6, a receiving tank 7, and an anti-surge valve. The outlet of the inlet separator is connected to the inlet of the refrigeration unit 3. One gas outlet of the refrigeration unit 3 is connected to the inlet of the receiving tank 7 via the outlet condenser 6. The vent gas of the receiving tank 7 is discharged from the top of the receiving tank 7, and the refrigerant flows out from the bottom of the receiving tank 7. The other gas outlet of the refrigeration unit 3 is connected to the inlet of the inlet separator via the anti-surge valve and the anti-surge cooler in sequence.
[0012] In this embodiment, there are two inlet separators, and correspondingly, there are two anti-surge coolers and two anti-surge valves, namely, a first-stage inlet separator 1, a second-stage inlet separator 2, an anti-surge valve a# 1, an anti-surge valve b# 2, an anti-surge cooler 4# 1, and an anti-surge cooler 5# 2. The first-stage inlet separator 1 corresponds to the anti-surge valve a# 1 and the anti-surge cooler 4#, and the second-stage inlet separator 2 corresponds to the anti-surge valve b# 2 and the anti-surge cooler 5# 2.
[0013] The refrigerant user returns the vaporized refrigerant to the first-stage inlet separator 1 and the second-stage inlet separator 2 of the refrigeration unit 3. The gas phase from the outlet of the first-stage inlet separator 1 and the second-stage inlet separator 2 enters the first-stage inlet and the second-stage inlet of the refrigeration unit 3, respectively. After being compressed by the refrigeration unit 3, the gas is condensed into a liquid phase by the outlet condenser 6 and flows into the receiving tank 7. The vent gas is discharged from the top of the receiving tank 7, and the refrigerant flows out of the refrigerant user from the bottom of the receiving tank 7. In order to ensure the inlet flow of the refrigeration unit 3, a portion of the gas from the outlet of the refrigeration unit 3 returns to the inlet of the refrigeration unit 3. There are two return paths. One path controls the flow through the #1 anti-surge valve a, passes through the #1 anti-surge cooler 4 and is cooled by circulating water before entering the first-stage inlet separator 1, and returns to the first-stage inlet of the refrigeration unit 3 from the top of the first-stage inlet separator 1. The other path controls the flow through the #2 anti-surge valve b, passes through the #2 anti-surge cooler 5 and is cooled by circulating water before entering the second-stage inlet separator 2, and returns to the second-stage inlet of the refrigeration unit 3 from the top of the second-stage inlet separator 2.
[0014] This invention relates to an anti-surge valve connected to an anti-surge cooler, which cools the gaseous refrigerant to the required temperature. The cooled temperature is higher than the saturation temperature of the refrigerant under the operating pressure, preventing liquefaction. The process eliminates the need for a refrigerant injector. Compared to a refrigerant injector, the cooler is a static device with better stability. This invention is simple and reliable to operate. The anti-surge cooler operates at a low pressure of 0.2–0.5 MPaG, with the circulating cooling water temperature generally in the range of 28–33°C. The gaseous refrigerant is cooled by the circulating water at the aforementioned operating pressure, keeping its temperature above the dew point, preventing liquefaction and avoiding the possibility of the compressor tripping due to excessively high liquid levels in the inlet separators. In contrast, a surge system with an aftercooler and refrigerant injection is prone to tripping under low-load conditions or injector failure due to excessively high liquid levels or inlet temperatures in the inlet separators. This invention fundamentally avoids these situations, ensuring safety, reliability, and a simple process, allowing the refrigeration unit to operate stably for extended periods.
Claims
1. A surge-resistant refrigeration unit assembly, characterized in that: The system includes an inlet separator, a refrigeration unit (3), an anti-surge cooler, an outlet condenser (6), a receiving tank (7), and an anti-surge valve. The outlet of the inlet separator is connected to the inlet of the refrigeration unit (3). One gas outlet of the refrigeration unit (3) is connected to the inlet of the receiving tank (7) via the outlet condenser (6). The venting gas of the receiving tank (7) is discharged from the top of the receiving tank (7), and the refrigerant flows out from the bottom of the receiving tank (7). The other gas outlet of the refrigeration unit (3) is connected to the inlet of the inlet separator via the anti-surge valve and the anti-surge cooler.
2. The anti-surge refrigeration unit assembly according to claim 1, characterized in that: There are two inlet separators, and correspondingly, there are two anti-surge coolers and two anti-surge valves, namely, a first-stage inlet separator (1), a second-stage inlet separator (2), an anti-surge valve (a) #1, an anti-surge valve (b) #2, an anti-surge cooler (4) #1, and an anti-surge cooler (5). The first-stage inlet separator (1) corresponds to the anti-surge valve (a) #1 and the anti-surge cooler (4), and the second-stage inlet separator (2) corresponds to the anti-surge valve (b) #2 and the anti-surge cooler (5).
3. The anti-surge refrigeration unit assembly according to claim 1, characterized in that: The anti-surge cooler operates at a low pressure of 0.2–0.5 MPaG.
4. The anti-surge refrigeration unit assembly according to claim 1, characterized in that: The circulating cooling water temperature of the anti-surge cooler is 28–33°C.