Title:
FREEZING METHOD
Document Type and Number:
Japanese Patent JP2021050841
Kind Code:
A
Abstract:
To provide a freezing method in which an HFO refrigerant is mixed with carbon dioxide to obtain a non-azeotropic mixed refrigerant.SOLUTION: In order to reduce the high pressure of a refrigeration circuit to 3.0 MPa or less by cooling by using a non-azeotropic mixed refrigerant that is a mixture of carbon dioxide and a non-fluorocarbon refrigerant as a refrigerant, a single heat transfer plate is provided inside a casing. The heat transfer plate forms a primary side and a secondary side with the same capacity through which the refrigerant flows, and a plurality of heat exchangers having the same heat transfer area on the primary side and the secondary side are connected in series, thereby forming a multi-stage evaporation/decompression mechanism. A pressure reducing valve is arranged in front of a secondary side inlet of each heat exchanger, and provided is an overall pressure adjustment valve that adjusts the overall pressure of the multi-stage evaporation/decompression mechanism before the refrigerant flows from a condenser to the multi-stage evaporation/decompression mechanism.SELECTED DRAWING: Figure 1
Inventors:
MATSUSHITA HIROAKI
Application Number:
JP2019172569A
Publication Date:
April 01, 2021
Filing Date:
September 24, 2019
Export Citation:
Assignee:
MAC KK
International Classes:
F25B1/00; F25B6/04
Domestic Patent References:
| JP2007187370A | 2007-07-26 | |||
| JPS56155277U | 1981-11-19 | |||
| JPH06331223A | 1994-11-29 | |||
| JPH07504490A | 1995-05-18 | |||
| JP2017138046A | 2017-08-10 |
Foreign References:
| WO2016013077A1 | 2016-01-28 | |||
| FR959329A | 1950-03-29 |
Attorney, Agent or Firm:
Akiyoshi Sato