摘要：With the agreement of the Kigali amendment to the Montreal Protocol, the timetable for the reduction of the mandate and the limitation of 18 controlled substances are being phased in. This has brought great challenges to the transformation, upgrading and sustainable development of China’s refrigeration and air conditioning industry. It has brought great challenges to the transformation, upgrading and sustainable development of China’s refrigeration and air conditioning industry. Carbon dioxide (CO 2 )is considered to be the most suitable and potential natural working medium due to its excellent environmental properties. This paper introduces the properties of CO 2 refrigerant, NH 3 /CO 2 laminated refrigeration system, CO 2 secondary refrigerant refrigeration system and CO 2 trans-critical refrigeration cycle system, and analyzes three representative processes of CO 2 refrigeration system.
