A brine system uses a salt-water or glycol solution as a secondary refrigerant to transfer heat between the primary refrigeration circuit and various cooling loads. The brine circulates through distribution piping without changing phase, allowing the refrigeration compressor to operate remotely in a central location. This configuration is standard in large industrial refrigeration facilities and food processing plants.
Technical Details
Calcium chloride and sodium chloride brines operate effectively to -25°C with thermal conductivity of 0.5-0.6 W/m·K and specific heat near 3.2 kJ/kg·K. Concentration levels between 20-30% by weight prevent ice formation while maintaining adequate heat transfer properties. Propylene glycol brines provide better corrosion resistance and lower toxicity. System temperatures typically maintain -15°C to -5°C brine delivery with circulation rates of 2-4 m/s in pipes sized for 0.5-1.5 m/s velocity.
Practical Applications
Brine systems serve ice rink floors, frozen food warehouses, and large-capacity blast freezers requiring precise temperature control across multiple zones. Advantages include simplified refrigerant management, reduced system charge, and flexible load distribution. Corrosion inhibitors and regular water quality monitoring prevent fouling and extend pump/heat exchanger service life to 10-15 years.