Hocheifel Pronsfeld Dairy Syndicate

Planning / Implementation / Main components

Axima Refrigeration GmbH, Lindau

Refrigerant

Ammonia (NH₃)

System start-up

2003/2004

Each year, the Germany-based Milch-Union Hocheifel eG, a dairy syndicate, processes some 830 million litres of milk into long-life dairy products like long-life milk, condensed milk and cream. To cope with the increasing volumes, the cooperative has extended its dairy facilities in recent years. Axima Refrigeration was commissioned to modernise the refrigeration facility.

Demands

Additional plants were to be added to the existing central refrigeration facility, to deliver reliable and environmentally friendly refrigeration to the production plants.

Solution

Axima Refrigeration enlarged the refrigeration facility by adding another, ammonia-run iced water tank including pre-cooling. The expansion increased the ice chiller's capacity to over twelve megawatts per hour. The iced water returned from production is cooled to 2 °C using the new iced water pre-cooling facility. The pre-cooled iced water then flows into the ice chiller, where it is cooled to 1 °C. The iced-water pumps then pump it back to the various cold consumers in production. The iced-water pre-cooling facility has the same refrigeration capacity as the central (ammonia) refrigeration unit, i.e. nearly two megawatts.

Type of facility

One-step plant

Refrigerant

NH₃

Refrigerant volume

12,000 kg

Refrigerating capacity

Central refrigeration plant: 2,000 kW
Iced water pre-cooling facility: 1,860 kW
Q0 = 3,660 kW at an evaporating temperature of -5 °C and condensation temperature of 35 °C
Iced water supply temperature 6 °C, return temperature 1 °C

Main components

4 reciprocating compressor units for the NH3 pump set up in the ice storage
2 screw compressors for the iced water pre-cooling facility
1 evaporation condenser

Special features / Comments

The iced water is cooled by means of a plate evaporator with built-over precipitator. The condenser's output is given off to the surrounding system via an evaporation condenser. The system has a control cabinet featuring Siemens S5 / S7 controls and an OP 17 console.