Liquefaction system and power generation system

Patent metadata

Field	Value
Publication number	US-10097067-B2
Application number	US-201615061178-A
Country	US
Kind code	B2
Filing date	Mar 4, 2016
Priority date	Mar 9, 2015
Publication date	Oct 9, 2018
Grant date	Oct 9, 2018

Abstract

Liquefier includes first compression section which is driven by a superconducting motor and which compresses a substance in a gaseous state. Cooling circuit includes: second compression section which is driven by the motor when first compression section is being driven by the motor and which compresses a refrigerant; first heat exchange section which cools the refrigerant by causing heat exchange between a substance in a tank and the compressed refrigerant; second expansion section which brings the refrigerant down to or below a critical temperature of a superconducting material by expanding the cooled refrigerant; and second heat exchange section which imparts cold heat of the refrigerant to the substance by causing heat exchange between the substance in the tank and the refrigerant after cooling a superconducting magnet, and supplies the refrigerant brought down to or below the critical temperature by second expansion section to the motor and cools the superconducting magnet.

First claim

The invention claimed is:

1. A liquefaction system comprising:
a storage tank which stores a substance, whose boiling point is equal to or lower than room temperature, in a liquid state;
a superconducting motor which includes a superconducting magnet constituted by a superconducting material;
a liquefier which includes a first compressor that is driven by the superconducting motor and that compresses the substance in a gaseous states and a first expansion section that changes the substance from a gaseous state to a liquid state by expanding the substance compressed by the first compressor, and which generates the substance in a liquid state to be stored in the storage tank; and
a cooling circuit which includes a second compressor that is driven by the superconducting motor when the first compressor is being driven by the superconducting motor and that compresses a refrigerant, a first heat exchanger that cools the refrigerant by causing a heat exchange between the substance stored in the storage tank and the refrigerant compressed by the second compressor, a second expansion section that brings the refrigerant down to or below a critical temperature of the superconducting material by expanding the refrigerant cooled by the first heat exchanger, and a second heat exchanger that imparts cooling of the refrigerant to the substance by causing a heat exchange between the substance stored in the storage tank and the refrigerant after cooling the superconducting magnet, and which supplies the refrigerant brought down to or below the critical temperature by the second expansion section to the superconducting motor and cools the superconducting magnet down to or below the critical temperature, wherein,
the first expansion section is a first expander or a first expansion valve,
the second expansion section is a second expander or a second expansion valve.

2. The liquefaction system according to claim 1 , wherein the storage tank includes:
a first space of the tank in which the substance is stored and in which the first heat exchanger and the second heat exchanger are arranged; and
a second space of the tank in which the superconducting motor, the second compressor, and the second expansion section are arranged, the first space of the tank and the second space of the tank being fluidly sealed and airtight from each other.

3. The liquefaction system according to claim 1 , further comprising
a heat-insulating airtight container which is mounted to the storage tank on the outside of the storage tank and which houses the superconducting motor, the second compressor, and the second expansion section, wherein
the first heat exchanger and the second heat exchanger are arranged in the storage tank.

4. The liquefaction system according to claim 1 , wherein
the second compressor is a screw compressor including a compression female rotor which is a screw rotor and a compression male rotor which is a screw rotor meshing with the compression female rotor,
the second expansion section is a screw expander including an expansion female rotor which is a screw rotor and an expansion male rotor which is a screw rotor meshing with the expansion female rotor,
the compression female rotor and the expansion female rotor are coupled to each other so as to be integrally rotatable around a same shaft,
the compression male rotor and the expansion male rotor are coupled to each other so as to be integrally rotatable around a same shaft, and
the superconducting motor rotates at least one of a rotating body which includes the expansion female rotor and the compression female rotor coupled to the expansion female rotor and another rotating body which includes the expansion male rotor and the compression male rotor coupled to the expansion male rotor.

5. The liquefaction system according to claim 2 , wherein
the second compressor is a screw compressor including a compression female rotor which is a screw rotor and a compression male rotor which is a screw rotor meshing with the compression female rotor,
the second expansion section is a screw expander including an expansion female rotor which is a screw rotor and an expansion male rotor which is a screw rotor meshing with the expansion female rotor,
the compression female rotor and the expansion female rotor are coupled to each other so as to be integrally rotatable around a same shaft,
the compression male rotor and the expansion male rotor are coupled to each other so as to be integrally rotatable around a same shaft, and
the superconducting motor rotates at least one of a rotating body which includes the expansion female rotor and the compression female rotor coupled to the expansion female rotor and another rotating body which includes the expansion male rotor and the compression male rotor coupled to the expansion male rotor.

6. The liquefaction system according to claim 3 , wherein
the second compressor is a screw compressor including a compression female rotor which is a screw rotor and a compression male rotor which is a screw rotor meshing with the compression female rotor,
the second expansion section is a screw expander including an expansion female rotor which is a screw rotor and an expansion male rotor which is a screw rotor meshing with the expansion female rotor,
the compression female rotor and the expansion female rotor are coupled to each other so as to be integrally rotatable around a same shaft,
the compression male rotor and the expansion male rotor are coupled to each other so as to be integrally rotatable around a same shaft, and
the superconducting motor rotates at least one of a rotating body which includes the expansion female rotor and the compression female rotor coupled to the expansion female rotor and another rotating body which includes the expansion male rotor and the compression male rotor coupled to the expansion male rotor.

Assignees

• Kobe Steel Ltd
• Japan Superconductor Tech Inc

Inventors

• Inoue Kenichi
• Saitou Kazuyoshi
• Zaitsu Kyoji
• Inoue Koji
• Ito Satoshi

Classifications

• H02K7/1823

  structurally associated with turbines or similar engines · CPC title

• F25J1/0236

  providing refrigeration for different processes treating not the same feed stream · CPC title

• F25J1/0257

  Construction and layout of liquefaction equipments, e.g. valves, machines (F25J1/0279 takes precedence) · CPC title

• F25J1/0022

  Hydrocarbons, e.g. natural gas · CPC title

• F25J1/0261

  Details of cold box insulation, housing and internal structure (buildings forming parts of cooling plants E04H5/10) · CPC title