FREEZING METHOD

• Main Author: MATSUSHITA HIROAKI
• Format: Patent
• Language: English; Japanese
• Published: 01.04.2021
• Subjects: BLASTING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; HEATING; LIGHTING; LIQUEFACTION SOLIDIFICATION OF GASES; MANUFACTURE OR STORAGE OF ICE; MECHANICAL ENGINEERING; REFRIGERATION MACHINES, PLANTS OR SYSTEMS; REFRIGERATION OR COOLING; WEAPONS

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 【課題】二酸化炭素にＨＦＯ冷媒を混合して非共沸混合冷媒とした冷凍方法を提供する。【解決手段】冷媒として二酸化炭素とノンフロン冷媒を混合した非共沸混合冷媒を用いて、冷凍回路の高圧を冷却によって３．０ＭＰａ以下とするために、ケーシングの内部に一枚の伝熱プレートを設け、その伝熱プレートによって、冷媒が流通する、同一の容量を有する一次側と二次側を形成し、前記した伝熱プレートの伝熱面積は一次側と二次側で同一とした熱交換器を直列に複数個連接して多段式蒸発減圧機構を構成し、各熱交換器の二次側流入口前には減圧弁を配し、凝縮器から前記多段式蒸発減圧機構へ冷媒が流入する前にはその多段式蒸発減圧機構の全体の圧力調整を行なう全体圧力調整弁を設けたこととする。【選択図】図１