Prosper de Mulder

Planning / Implementation / Main components

Star Refrigeration Ltd.

Refrigerant

Carbon dioxide (CO₂), secondary refrigerant Ammonia (NH₃)

System start-up

2003

Prosper de Mulder, the UK's largest pet food processor, had a requirement for an efficient plate freezing system to replace the old R-22 system for their pet food production facility in Doncaster, England.

Demands

Replacement of the old refrigeration plant which used R-22 with a non ozone depleting refrigerant which would not be subject to impending F-gas regulations.

Solution

Installation of an environmentally friendly and highly efficient plate freezer system using carbon dioxide as the refrigerant with ammonia condensers.

Type of facility

Vertical plate freezer system

Refrigerant

CO₂

Secondary Refrigerant

NH₃

No. of refrigeration compressors

2

Refrigerant temperature

CO₂ -50 ºC, NH3 -40 ºC

Refrigerating capacity

1,000 kW

Main components

Screw compressors, surge drum/pump set, 16 plate freezers

Special features / Comments

The main environmental benefit is the low energy consump-tion of this system. The combination of CO2 with pressurized liquid defrost for a plate freezing system is a world first. Freezing times are 75 % of the traditional system and the system is running more efficiently at far lower temperatures without causing excessive power consumption.