JP2012189314A - Refrigeration equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide refrigeration equipment, in which the entire compressor mass flow can be used in substantially any temperature level without requiring usage of an auxiliary cryogen.SOLUTION: The refrigeration equipment includes: at least one compressor operating to compress a cryogen that circulates in a cold cyclic path; a plurality of heat exchangers HX1, HX2, HX3, HX4, HX5 and HX6; and expansion devices TU1 and TU2 that operate at different temperature levels from each other. In the expansion devices, at least temporarily, at least one partial stream of the cryogen is expanded to generate cold. The refrigeration equipment is further provided with at least one additional expansion device TU3. The additional expansion device TU3 is embedded in the cold cyclic path in such a manner that the cryogen circulating in the cold cyclic path is, at least temporarily after cooling a cooling target, at least partially expanded in the additional expansion device TU3 to generate cold.

Description

The present invention is a refrigeration facility for cooling an object to be cooled,
-A cold circuit is provided,
-At least one compressor is provided which serves to compress the cryogen circulating in the cold circuit;
-A plurality of heat exchangers are provided, in which the cryogen is cooled relative to the cryogen itself;
-At least two expansion devices operating at different temperature levels are provided, in which at least a partial flow of the cryogen is expanded at least temporarily to generate cold.
Relating to the type of refrigeration equipment.

  The invention further relates to a method for operating a refrigeration facility.

  A refrigeration installation of the type mentioned at the outset and a method for operating the refrigeration installation mentioned at the outset are known, for example, from the unpublished German patent application 102011009655.

  Such a type of refrigeration equipment is usually used for cooling or heating a cryogenic load (kryogen. Last), for example a superconducting magnet, to be cooled. For this, the Claude-Prozess is used. Cooling is usually done from ambient temperature to a temperature of 5K. The Claude process is designed for the specified cooling temperature. When cooling at another temperature level is required, such as during controlled cooling or heating of a superconducting electromagnet, there is sufficient flow cross-section, especially inside the expansion stage that generates cold. Yes. This results in the existing compressor mass flow being only partially available in these expansion stages. That is, facility drive output is provided for cold generation only at a limited scale during such times.

  In order to avoid this problem, the already realized solution is that the compressor mass flow is supplemented with a supplemental cryogen (usually liquid nitrogen) before the unavailable compressor mass flow assists in cooling the object to be cooled. Is cooled via an additional heat exchanger and temperature controlled over the mixing section. However, a disadvantage in this case is that the use of the full compressor mass flow is only possible due to the additional auxiliary cryogen consumption.

German Patent Application No. 102011009965

  The problem of the present invention is to improve the refrigeration system of the type mentioned at the outset so that the full compressor mass flow can be used at almost any temperature level without the need for supplemental cryogens to be used. It is to provide refrigeration equipment.

  It is a further object of the present invention to provide a method for operating such a refrigeration facility.

  In order to solve this problem, in the configuration of the refrigeration equipment of the present invention, at least one other expansion device (third expansion device) is provided, and the other expansion device circulates in the cold circuit. The cryogen is incorporated in the cold circuit so that it is at least temporarily expanded at least partially in the separate expansion device after the cooling of the object to be cooled to generate cold.

  Furthermore, in order to solve the above problems, the method for operating the refrigeration equipment of the present invention is such that the compressor mass flow is cooled during the cooling process and / or the heating process. The three expansion devices are distributed so as to work for cooling the cooling target.

  The refrigeration facility according to the present invention allows the use of full compressor mass flow at almost any temperature level, without the need for supplemental cryogens to be used.

1 is a circuit diagram showing an embodiment of a refrigeration facility according to the present invention.

  In the following, embodiments for carrying out the invention will be described in detail with reference to the drawings.

  The refrigeration equipment shown in FIG. 1 includes a plurality of heat exchanges, that is, first to sixth heat exchangers HX1, HX2, HX3, HX4, HX5, HX6, a separator D, and a plurality of control valves, that is, a first heat exchanger. To ninth control valve V1, V2, V3, V4, V5, V6, V7, V8, V9 and three expansion devices, that is, three expansion devices TU1, TU2, TU3. Below, the cooling process and heating process of the cryogenic cooling object to be cooled by the refrigeration equipment according to the present invention will be described in detail.

  At the start of the cooling process, the temperature of the cryogenic cooling object to be cooled is about 300K. A cryogen compressed to a desired circulation pressure by a compressor (not shown) is supplied to the first heat exchanger HX1 via the pipe line 1. In the state where the seventh control valve V7 is opened, the partial flow of the cryogen is supplied to the cooling target (load) to be cooled through the pipeline sections 1, 2, and 3. The heated cryogen is withdrawn from the object to be cooled through the pipeline 4 in the state in which the ninth control valve V9 is opened, and after the cooling in the second heat exchanger HX2, the pipeline sections 4 ', 20, It is supplied to the third expansion device TU3 via 21 and is expanded in the third expansion device TU3 to generate cold.

  Subsequently, the expanded cryogen partial flow passes through the pipe sections 22, 23, 6 to the fourth heat exchanger HX4, the third heat exchanger HX3, the second heat exchanger HX2, and the first heat exchanger. After passing through HX1, it is again guided to the front (upstream side) of the compressor or compression unit of the refrigeration equipment according to the present invention.

  The partial flow of the cryogen supplied to the object to be cooled is supplied to the second expansion device TU2 via the pipe line 13 with the second control valve V2 opened, and the second expansion device TU2 expands. Then, cold is generated, and subsequently mixed with the cryogen flow drawn from the object to be cooled in the pipe section 4 ′ via the pipe sections 14 and 15. The third heat exchanger HX3 has a bypass line 12, and a fourth control valve V4 is arranged in the bypass line 12. The inlet temperature of the second expansion device TU2 can be controlled in a closed loop manner by the second and fourth control valves V2, V4.

  The cryogen flow that has not been supplied to the third expansion device TU3 is expanded to a low pressure via the pipe line 5 in which the fifth control valve V5 is arranged, or mixed into the cryogen flow in the pipe line 6. Is done. As the return temperature decreases, the flow rate through the fifth control valve V5 gradually decreases and finally decreases completely.

  At the same time, a first expansion device TU1 is connected, and this first expansion device TU1 is amplified and output loaded as the return temperature decreases. For this purpose, a part of the compressed cryogen flow is supplied to the first expansion device TU1 via the line 10 in which the first control valve V1 is arranged, and after the expansion is performed, the pipe It mixes with the cryogen flow supplied to the 3rd expansion apparatus TU3 via the path | route 11.

  During this cooling phase, a permanently small amount of cryogen partial flow is passed through the sixth heat exchanger HX6 and the fifth through the sixth control valve V6 and the eighth control valve V8, which are slightly opened. The sixth heat exchanger HX6 and the fifth heat exchanger HX5 are simultaneously cooled together.

  The object to be cooled can be cooled to a temperature of about 100K by the process or process described above. In order to continue cooling to a temperature of about 30 K, the seventh control valve V7 and the ninth control valve V9 are closed, and the sixth control valve V6 and the eighth control valve V8 are further opened. Is done.

  The cryogen supplied to the object to be cooled is then divided into two partial streams. The first cryogen partial stream is guided via the first expansion device TU1, and thus supplied to the object to be cooled via the duct sections 10, 11, 20, 15, 40, while the second cryogen part is supplied to it. The flow is supplied to the object to be cooled via the second expansion device TU2 and thus via the pipeline sections 2, 13, 14, 40. During the cooling process, the mass flow supplied to the third expansion device TU3 is gradually reduced, and finally the third expansion device TU3 is connected to the upstream side of the third expansion device TU3. Mass flow is supplied only from one expansion device TU1.

  In order to achieve the last stage of the cooling process (in this case, cooling of the object to be cooled to a temperature of about 5K takes place), the third expansion device TU3 is increasingly tightened as the return temperature decreases. Yuki is finally stopped. The compressor mass flow then flows to the object to be cooled only in parallel in this case, but only via the first and second expansion devices TU1, TU2 working at different temperature levels. The cryogen flow returning from the object to be cooled is discharged into the phase separator D through the eighth control valve V8. Due to the Joule-Thomson-Effekt effect occurring at this temperature, the cryogen stream is once again cooled and partially liquefied. The liquefied cryogen is guided through the sixth heat exchanger HX6 via the line section 32 and evaporated in countercurrent form, and the vapor component from the phase separator D is directly passed through the line section 31. To the fifth heat exchanger HX5.

  During the heating process, the previously described method sequence is carried out in reverse order.

  As can be seen from the method implementation described above, the total compressor mass flow is provided for complete cooling at both the cooling and heating stages.

  Compared to a refrigeration facility, for example as described in the German patent application 102011009655 mentioned at the outset, the refrigeration facility according to the invention comprises at least three additional process lines, including the associated valve. have. This allows distribution of the remaining compressor mass flow. This distribution allows the entire compressor mass flow to be utilized for cooling the cryogenic cooling object at any point in time.

  When using a refrigeration facility according to the present invention, or using a method that can be realized by the refrigeration facility according to the present invention, the entire compressor mass flow can be utilized for cold generation. Thereby, the refrigeration equipment according to the present invention achieves maximum efficiency during operation, that is, during the cooling process and heating process of the cryogenic cooling object. This can obviate the use of additional supplemental cryogens that were previously required.

HX1, HX2, HX3, HX4, HX5, HX6 Heat exchanger D Separator V1, V2, V3, V4, V5, V6, V7, V8, V9 Control valve TU1, TU2, TU3 Expansion device

Claims (3)

A refrigeration facility for cooling an object to be cooled,
-A cold circuit is provided,
-At least one compressor is provided which serves to compress the cryogen circulating in the cold circuit;
-A plurality of heat exchangers (HX1, HX2, HX3, HX4, HX5, HX6) are provided, in which the cryogen is cooled against the cryogen itself;
-Two expansion devices (TU1, TU2) operating at different temperature levels are provided, in which at least a partial flow of the cryogen is expanded at least temporarily in the expansion devices to generate cold. ,
In the type of refrigeration equipment,
At least one other expansion device (TU3) is provided, and the other expansion device (TU3) is at least temporarily at least partially after the cooling agent circulating in the cold circuit is cooled to be cooled. A refrigeration facility for cooling an object to be cooled, which is incorporated in a cold circuit so as to be expanded in the expansion device (TU3) and generate cold.   2. A method for operating a refrigeration facility as claimed in claim 1, wherein the compressor mass flow during the cooling and / or heating process is such that the entire compressor mass flow is at substantially any time for cooling the object to be cooled. A method for operating a refrigeration facility, characterized in that it is distributed to the three expansion devices (TU1, TU2, TU3) so as to work.   Use of a refrigeration facility according to claim 1, characterized in that the refrigeration facility serves for cooling a cryogenic cooling object, preferably a superconducting electromagnet.

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