Case study
Lekkerland
Deep-freeze warehouses and refrigerated storage facilities
Key information
Client:
Lekkerland
Supplier:
SSP Kälteplaner AG
Type of facility:
Cascade system
System start-up:
2008
Lekkerland is a wholesale company for food, beverages, tobacco, telecommunication and other non-food products. The wholesaler has installed deep-freeze warehouses and refrigerated storage facilities at all three German sites in Oberhausen, Stapelfeld and Allershausen. In spite of the higher investment costs involved, Lekkerland has opted for ammonia and carbon dioxide as natural refrigerants.
Requirement
The objective was to ensure environment-friendly refrigeration on the basis of a comprehensive concept for the three deep-freeze warehouses and refrigerated storage facilities using the same technical systems.
Solution
SSP Kälteplaner has planned an installation working with the natural refrigerant ammonia for normal refrigeration and carbon dioxide for deep-freeze refrigeration. The ammonia gases compressed by two screw compressors are condensed with air-cooled condensers. A secondary refrigerant system is used for the refrigerated storage facilities, operating with a water/glycol mixture at a flow temperature of -8°C. The refrigerated stores are cooled to 0°C and the loading zones to 5°C. Frequency converters are fitted to the screw compressors of the ammonia system.
Technical data
Cooling capacity:
600 kW
Refrigerant volume:
350 kg CO2
Secondary refrigerant:
Water/glycol mixture
Main components:
2 screw compressors (NH3 speed-controlled), 2 piston compressors (CO2), no-frost refrigerator, evaporator in deep-freeze warehouse with defrost flaps
Special features:
The glycol no-frost refrigerators are defrosted with power pack defrost stations which heat the secondary refrigerant. The waste heat from the oil coolers is used for heating.
