SWITCHABLE TWO-STAGE AND CASCADE MARINE ENERGY-SAVING ULTRALOW-TEMPERATURE REFRIGERATION SYSTEM

• US 20160334143A1
• Filed: 06/17/2016
• Published: 11/17/2016
• Est. Priority Date: 05/12/2015
• Status: Active Grant

• Current Assignee: Shanghai Ocean University
• Original Assignee: Shanghai Ocean University
• Inventors: Guo, Yaojun, Li, Yizhe, Xu, Minsheng, Xie, Jing, Wang, Jinfeng
• Granted Patent: US 10,107,526 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F25B 2339/047 Water-cooled condensers
• CPC Class Codes: F25B 2400/054 between the suction tube of the compressor and another part of the cycle
• CPC Class Codes: F25B 2400/13 Economisers
• CPC Class Codes: F25B 41/20 Disposition of valves, e.g. of on-off valves or flow control valves expansion valves F25B41/31
• CPC Class Codes: F25B 41/385 Dispositions with two or more expansion means arranged in parallel on a refrigerant line leading to the same evaporator
• CPC Class Codes: F25B 41/39 Dispositions with two or more expansion means arranged in series, i.e. multi-stage expansion, on a refrigerant line leading to the same evaporator
• CPC Class Codes: F25B 43/003 Filters
• CPC Class Codes: F25B 43/02 for separating lubricants from the refrigerant
• CPC Class Codes: F25B 47/022 hot gas defrosting
• CPC Class Codes: F25B 49/02 for compression type machines, plants or systems
• CPC Class Codes: F25B 5/02 arranged in parallel
• CPC Class Codes: F25B 7/00 Compression machines, plants or systems, with cascade operation, i.e. with two or more circuits, the heat from the condenser of one circuit being absorbed by the evaporator of the next circuit F25B9/00 takes precedence

Abstract

The present invention discloses a switchable two-stage and cascade marine energy-saving ultralow-temperature refrigeration system which comprises a high-temperature level refrigeration system, a low-temperature level refrigeration system, a hot fluorine defrosting system of a high-temperature level air cooler and a hot fluorine defrosting system of a low-temperature level air cooler. The hot fluorine defrosting system of the high-temperature level air cooler comprises a high-temperature level compressor of which the outlet is divided into two paths through a first oil separator; and the second path is connected with an air suction port of the high-temperature level compressor through a first solenoid valve, the high-temperature level air cooler, a third solenoid valve, a first pressure relief valve, a first gas-liquid separator, a first one-way valve and a first heat regenerator. The hot fluorine defrosting system of the low-temperature level air cooler comprises a low-temperature level compressor of which the outlet is divided into two paths through a precooler and a second oil separator; and the second path is connected with an air suction port of the low-temperature level compressor through an eighth solenoid valve, the low-temperature level air cooler, a sixth solenoid valve. a second pressure relief valve, a second gas-liquid separator, a third one-way valve and a second heat regenerator. The present invention has the obvious effects of large refrigeration section, high cooling rate, good energy-saving effect and thorough defrosting.

Claims

1. A switchable two-stage and cascade marine energy-saving ultralow-temperature refrigeration system, comprising a high-temperature level refrigeration system, a low-temperature level refrigeration system, a hot fluorine defrosting system of a high-temperature level air cooler and a hot fluorine defrosting system of a low-temperature level air cooler and characterized in that

(1) the high-temperature level refrigeration system is a stand-alone two-stage refrigeration system;

(2) the high-temperature level refrigeration system comprises a high-temperature level compressor (a first oil separator (2), a second solenoid valve (4), a water-cooling condenser (5), a liquid reservoir (6), a high-temperature level drying filter (7), a first electronic expansion valve (8), an intercooler (9), a first heat regenerator (10), a fourth solenoid valve (17), a second electronic expansion valve (16), a second one-way valve (15), a high-temperature level air cooler (41), a tenth solenoid valve (40), a sixth one-way valve (39), a fifth solenoid valve (19), a third electronic expansion valve (18), a condensation evaporator (37) and a fifth one-way valve (38) which are connected on a pipeline;

(3) an outlet of the high-temperature level compressor (1) is connected with an inlet of the first oil separator (2), the outlet of the first oil separator (2) is divided into two paths;

the first path is connected with an inlet of the water-cooling, condenser (5) through the second solenoid valve (4);

an outlet of the water-cooling condenser (5) is connected with the liquid reservoir (6);

an outlet of the liquid reservoir (6) is connected with an inlet of the high-temperature level drying filter (7);

an outlet of the high-temperature level drying filter (7) is divided into two paths;

the first path is communicated with the high-temperature level compressor (1) through the first electronic expansion valve (8) and the intercooler (9);

the second path is connected with one inlet of the first heat regenerator (10) through the intercool outlet of the first heat regenerator (10) is divided into two paths;

the first path is connected with the high-temperature level air cooler (41) through the fourth solenoid valve (17), the second electronic expansion valve (16) and the second one-way valve (15);

the high-temperature level air cooler (41) is connected with the high-temperature level compressor (1) through the tenth solenoid valve (40), the sixth one-way valve (39) and the first heat regenerator (10);

the second path is connected with a low-temperature passage of the condensation evaporator (37) through the fifth solenoid valve (19) and the third electronic expansion valve (18); and

an outlet of the low-temperature passage of the condensation evaporator (37) is connected with the high-temperature level compressor (1) through the fifth one-way valve (38) and the first heat regenerator (10);

(4) the low-temperature level refrigeration system comprises a low-temperature level compressor (32), a precooler (33), a second oil separator (35), a ninth solenoid valve (36), a condensation evaporator (37), a low-temperature level drying filter (20), a second heat regenerator (21), a liquid lens (22), a fourth electronic expansion valve (23), a fourth one-way valve (27), a low-temperature level air cooler (29), a seventh solenoid valve (30) and an expansion vessel (31) which are connected on a pipeline;

(5) an outlet of the low-temperature level compressor (32) is connected with an inlet of the second oil separator (35) through the precooler (33);

the outlet of the second oil separator (35) is divided into two paths;

the first path is connected with a high-temperature passage of the condensation evaporator (37) through the ninth solenoid valve (36);

the high-temperature passage of the condensation evaporator (37) is connected with the low-temperature level drying filter (20);

the outlet of the low-temperature level drying filter (20) is connected with one inlet of the second heat regenerator (21); and

one outlet of the second heat regenerator (21) is connected with the low-temperature level compressor (32) through the liquid lens (22), the fourth electronic expansion valve (23), the fourth one-way valve (27), the low-temperature level air cooler (29) and the seventh solenoid valve (30).

2. The switchable two-stage and cascade marine energy-saving ultralow-temperature refrigeration system according to claim 1, characterized in that the hot fluorine defrosting system of the high-temperature level air cooler comprises a high-temperature level compressor (1), a first oil separator (2), a first solenoid valve (3), a high-temperature level air cooler (41), a third solenoid valve (14), a first pressure relief valve (13), a first gas-liquid separator (12), a first one-way valve (11) and a first heat regenerator (10) which are connected on a pipeline;

the outlet of the high-temperature level compressor (1) connected with the inlet of the first oil separator (2);

the outlet of the first oil separator (2) is divided into two paths the second path is connected with the first gas-liquid separator (12) through the first solenoid valve (3), the high-temperature level air cooler (41), the third solenoid valve (14) and the first pressure relief valve (13); and

the outlet of the first gas-liquid separator (12) is connected with the high-temperature level compressor through the first one-way valve (11) and the first heat regenerator (10).

3. The switchable two-stage and cascade marine energy-saving ultralow-temperature refrigeration system according to claim 1, characterized in that the hot fluorine defrosting system of the low-temperature level air cooler comprises a low-temperature level compressor (32), a precooler (33), a second oil separator (35), an eighth solenoid valve (34), a low-temperature level air cooler (29), a sixth solenoid valve (28), a second pressure relief valve (26), a second gas-liquid separator (25), a third one-way valve (24), a second heat regenerator (21) and an expansion vessel (31) which are connected on a pipeline;

the outlet of the low-temperature level compressor (32) is connected with the inlet of the second oil separator (35) through the precooler (33);

the outlet of the second oil separator (35) is divided into two paths;

the second path is connected with the second gas-liquid separator (25) through the eighth solenoid valve (34), the low-temperature level air cooler (29), the sixth solenoid valve (28) and the second pressure relief valve (26); and

the outlet of the second gas-liquid separator (25) is connected with the low-temperature level compressor (32) through the third one-way valve (24) and the second heat regenerator (21).

4. The switchable two-stage and cascade marine energy-saving ultralow-temperature refrigeration system according to claim 1, characterized in that the high-temperature level compressor (54) and the low-temperature level compressor (43) are variable frequency screw compressors.

5. The switchable two-stage and cascade marine energy-saving ultralow-temperature refrigeration system according to claim 1, characterized in that the high-temperature level refrigeration system is the stand-alone two-stage refrigeration system and can be used as an independent refrigeration system.

6. The switchable two-stage and cascade marine energy-saving ultralow-temperature refrigeration system according to claim 1, characterized in that in the high-temperature level refrigeration system, the fifth solenoid valve (19) is started and the fourth solenoid valve (17) is closed for realizing switching from the two-stage compression refrigeration system to the cascade compression refrigeration system.

7. The switchable two-stage and cascade marine energy-saving ultralow-temperature refrigeration system according to claim 1, characterized in that the condensation evaporator (37) is a plate type heat exchanger.

8. The switchable two-stage and cascade marine energy-saving ultralow-temperature refrigeration system according to claim 1, characterized in that a refrigerant R404A is applied to the high-temperature level refrigeration system and a refrigerant R23 is applied to the low-temperature level refrigeration system.