Classification by Refrigerant Type
Ammonia Refrigeration: Offers high cooling capacity and low operating costs; capable of operating at very low temperatures. Commonly used in large-scale freezing and quick-freezing facilities; requires strict leak prevention measures.
Freon Refrigeration: Features high automation and minimal temperature fluctuations; leaks have little impact on stored products. Suitable for small-to-medium cold storage, controlled-atmosphere storage, and various air-cooled cold storage facilities.
CO₂/Mixed Refrigerant: Highly eco-friendly; uses natural refrigerants with no risk of greenhouse gas emissions. Ideal for large-scale, low-temperature cold storage facilities prioritizing green, low-carbon operations.
Classification by Cooling Method
Direct Cooling: The evaporator is installed directly inside the storage room; the evaporating refrigerant absorbs heat directly from the space. Offers rapid cooling and a simple system design; the most widely used method.
Indirect Cooling: Heat transfer is mediated by a secondary coolant (such as brine or water). The system operates stably and provides thermal storage capabilities; suitable for specialized cold storage requiring precise temperature stability.
Air-cooled/Water-cooled/Evaporative-cooled: Air-cooled systems are easy to install and require no additional water resources; water-cooled systems offer uniform and stable cooling; evaporative-cooled systems combine the advantages of both, offering higher heat exchange efficiency.
Classification by System Principle
Vapor Compression: Currently the most widely used mainstream refrigeration method. It relies on a compressor to raise refrigerant pressure and complete the cycle; common compressor types include reciprocating (piston), screw, and scroll models.
Absorption: Relies on an absorber-generator assembly to complete the refrigeration cycle. Common types include ammonia-water and lithium bromide systems; capable of utilizing waste heat for operation, thereby reducing energy consumption.