Reduction in temperature of liquids is obtained using an intermediate refrigerant, by operating a cycle including the following phases:
• Evaporation
• Compression
• Condensation
• Expansion
The most used refrigerants are Freon or ammonia.
The refrigeration unit’s capacity depends on a series of factors such as inlet and outlet temperature of liquid being cooled, temperature and output of cooling air or condensation water.
Evaporators with scraped surface (FRIGOUNIVERSAL)
The complete unit includes:
• One or more evaporators in stainless steel, in which, flowing continuously, the liquid to cool transfers heat directly to refrigerant;
• Compressor of hermetic, semihermetic or open type;
• Condenser, water or air cooled;
• Valves, safety and control instruments, electric switch-board.
The side of tubular elements in contact with the liquid is continuously scraped by rotating blades; the refrigerant evaporates on the other side. The liquid to be cooled flows continuously in the chamber delimited by tubular elements and two head ends, one supportingt the motorization for rotation of scraping blades.
Each module is thermically insulated with Polyurethane foam.
Due to surface scraping, high performance in heat transfer and uniform cooling of liquid even at high viscosity are obtained.
Evaporators of dry expansion type
Refrigerant is normally Freon.
Evaporators of flooded type
Refrigerant is normally Ammonia.