Star builds Kuehne+Nagel coldstore

Milton Keynes, UK: Kuehne+Nagel has installed  an environmentally-efficient chill store cooling system at its chilled storage facility at its Brinklow site, near Milton Keynes that handles food and drink logistics for a UK supermarket.

Star Refrigeration, which has worked on other Kuehne+Nagel  projects, worked in partnership with the main contractor, to design and build the refrigeration plant for the new chill store.

The high-efficiency refrigeration plant incorporates two of Star’s Azanechillers.  The compact ammonia packaged chillers supply cooling to the 5,000sq metre chamber for chilled goods and a 4,000sq metre produce chamber for fresh fruit and vegetables.  Each temperature controlled chamber has a throughput of around 30 tonnes per hour.

Kuehne+Nagel's refrigeration plant incorporates two Star Azanechillers

Star combined the new Azanechiller system with an existing refrigeration plant to give Kuehne+Nagel the flexibility to operate the two chambers within the new chill store at different temperatures.  The existing plant allows the fresh produce chamber to operate at +9ºC, with the new Azanechiller system enabling an operating temperature of +2ºCelsius in the chilled goods chamber.

“Working to a strict time schedule, Star pre-commissioned and performance tested the Azanechiller system at its Glasgow manufacturing facility to reduce installation time on site at Brinklow.  Group company Star M&E Solutions was awarded the role of mechanical and electrical contractor, including main low voltage panel works, lighting for the two chambers, fire alarm and alterations to the ventilation system,” Star says.

The Kuehne+Nagel system features two air-cooled Azanechillers with ammonia as primary and glycol as secondary refrigerant.  Each unit has a cooling capacity of 400kW and features a low ammonia charge of less than 0.45kg/kW.  The Azanechillers are located externally, mounted on concrete plinths adjacent to the existing plant room.

As an environmentally conscious natural refrigerant with zero global warming and ozone depletion potential, ammonia overcomes concerns over HFCs.  Waste heat from the Azanechillers is recovered for defrosting the evaporators in the new and existing refrigeration plant.

The Azanechiller refrigeration package, suits temperature-controlled storage as well as food processing, building services and process cooling, Star says.  “Only an electrical supply and flow/return pipework is required to provide cooling.  This reduces site installation and commissioning time, whilst also avoiding the need for a plant room,” Star says.

Azanechiller was developed by Star for environmentally conscious end users.  Azanechiller typically offers a 30% increase in performance compared with standard HFC chillers.  Its packaged design and careful component selection result in an ultra low refrigerant charge, with all ammonia contained within the chiller and sited outside the warehouse or production facility.

“Azanechiller features high quality, industrial components to offer unrivalled performance, reliability and low maintenance.  Each unit includes two screw compressors, low noise drive motors, Star’s low charge low pressure receiver and semi-welded PHE evaporator.  Star’s Telstar computerised control system ensures optimum performance, with HMI touch screen interface and optional broadband connection for offsite remote monitoring,” the company says.

Azanechiller is available as an air-cooled or water-cooled unit with cooling capacity from 200kW to 850kW.  Air-cooled Azanechillers feature high efficiency EC condenser fan technology.  Water-cooled Azanechillers include a welded plate heat exchanger condenser to minimise refrigerant charge. Both include floating header pressure control, which optimises efficiency at part load conditions and low ambient temperatures.