Dairy Case Studies

  • Arla Foods


    Star Refrigeration has installed a high efficiency multi-temperature cooling plant at Arla Foods in West Yorkshire.

    The project by industrial cooling and heating specialist Star formed part of Arla’s third phase of investment in additional production facilities at its flagship dairy in Stourton, Leeds. Having been involved in refrigeration works throughout the previous construction phases, Star was responsible for designing a high efficiency cooling system to allow Arla to manufacture cottage cheese for the first time in the UK.

    With an overriding commitment to reduce energy consumption and CO2 emissions, Arla was looking for an environmentally conscious cooling solution. Star designed, supplied and installed a state-of-the-art central ammonia refrigeration plant, with energy saving equipment and control.

    The plant has a 5MW total cooling demand and operates at three separate temperature levels. A chilled water circuit provides cooling for the building’s heating, ventilation and air conditioning (HVAC) systems. Ice water is circulated to meet various process cooling demands within the production facility. Sub-zero glycol also provides cooling for a 2°C cold store and a blast chilling tunnel.

    Star Refrigeration’s Group Sales and Marketing Director Rob Lamb says: “Arla’s main focus was on an energy efficient, environmentally-sound cooling solution and we worked in close partnership on the design of the system. We opted for naturally occurring ammonia refrigerant because it has zero global warming potential and is non-ozone depleting.”

    He adds: “The installation of a central plant with three different cooling temperatures for process, HVAC and cold storage requirements ensured that refrigeration for each demand was achieved at maximum efficiency.”

    The central ammonia system consists of five screw compressors, three featuring inverter drives to optimise part load efficiency. Heat is rejected via three evaporative condensers with inverter driven fans that are located above the plant on the roof of the building. Other energy saving features include inverter controls for the glycol/water circulation pumps, floating head pressure control and floating suction pressure control.

    Star’s Telstar computerised control system constantly monitors and adjusts operating conditions to optimise efficiency. Star also provides an online 24-hour a day fault monitoring service.

    As well as supplying all of the plant room equipment, Star was responsible for the installation of a 1.5MW cooling tower for high temperature process water cooling, a number of coldstore coolers and associated pipework.

    When it comes to designing energy efficient cooling and heating systems, Star is a natural innovator. Star works with strategic partners across the globe to deliver low carbon, cost saving solutions.


  • Recent Dairy Installations


    ROBERT WISEMAN DAIRIES

    The Wiseman’s plant reflects the latest technology in terms of energy efficiency including floating head pressure control. The lead compressor, both condensers and all 9 glycol pumps are inverter driven.

    • 2007
    • Bridgwater
    • £1.4M
    • Ammonia/Glycol for process & Chillstore loads
    • 2,700kW process load & 550kW Chillstore load
    • 4 x Star built Grasso ‘S’ compressor packages
    • 2 x BAC CXV evaporative condensers
    • 2 x 1,625kW plate heat exchangers cooling glycol to -2°C
    • 10 x glycol air coolers for Chillstore
    • 1 x glycol buffer tank
    • 9 x glycol pumps

    ARLA DAIRIES

    The Lockerbie project involved the refurbishment and re-location of existing plant from two different sites involving careful coordination and planning between three different Star branches.

    • 2005
    • Lockerbie
    • £450K
    • Ammonia/Chilled Water for process load & R404a for Chillstore
    • 1,523kW process load & 200kW Chillstore load
    • 3 x Sabroe SMC 112 ammonia compressors
    • 1 x BAC CXV ammonia evaporative condenser
    • 1 x baudelot water chiller & tank cooling water to 0.5°C
    • 1 x R404a compressor pack incorporating 3 off Bitzer reciprocating machines each rated at 66kW
    • 1 x R404a air-cooled condenser & HPR
    • 1 x HPR
    • 4 x Chillstore evaporators each rated at 50kW

    ARLA DAIRIES

    The Stourton project required very close control of the chilled water temperature and a very close approach temperature. Star naturally delivered a successful solution, installing equipment that achieved a chilled water supply temperature of 0.7°C ± 0.1°C.

    • 2004 - 2005
    • Stourton (Leeds) Phases 1 & 2
    • £1.5M
    • Ammonia/Chilled Water for process load & packaged glycol chillers for Chillstore
    • 3,500kW process load & 840kW Chillstore load
    • 3 x Star built Grasso ‘H’ ammonia compressor packages
    • 2 x BAC VXC evaporative condensers
    • 3 x 1,500kW spray chillers cooling water to 0.7°C
    • 2 x air-cooled packaged glycol chillers for Chillstore cooling each rated at 420kW
    • 12 x Chillstore coolers each rated at 70kW complete with ‘Integrated Defrost System’

    DAIRYCREST

    The Stonehouse project involved the replacement of an existing, aged and unreliable R22 plant with efficient, modern equipment utilising food grade mono-propylene glycol as a secondary refrigerant.

    • 2004
    • Stonehouse, Gloucester
    • £300K
    • R407C/Glycol & 270kW Chillstore load
    • 1 x water-cooled packaged glycol chiller for Chillstore cooling rated at 300kW comprising 3 x semi-hermetic screw compressors
    • 1 x existing site cooling tower
    • 2 x glycol pumps
    • 2 x Chillstore coolers each rated at 90kW complete with ‘Integrated Defrost System’
    • 3 x Chillstore coolers each rated at 30kW complete with ‘Integrated Defrost System’

    MILKLINK

    By providing a solution that reused much of the existing ammonia plant at Staplemead, Star enabled a cost effective alternative to the use of hired air-cooled chillers.

    • 2006
    • Staplemead, Frome
    • £45K
    • Ammonia/Chilled Water
    • 500kW chilled water process load
    • 1 x Star built package unit comprising plate heat exchanger & surge drum to replace existing submerged coil type evaporator
    • Reuse of existing ammonia compressor and condenser plant

    PRITCHITTS

    The Pritchitts project required close control of the chilled water temperature and a close approach temperature. Star delivered a successful solution by installing a bespoke low temperature version of their standard water-cooled Indigochiller. As well as satisfying temperature control issues the equipment offers unrivalled efficiency by utilising cutting edge variable speed Danfoss Turbocor compressors.

    • 2005
    • Newtownards, Northern Ireland
    • £252K
    • R134A/Chilled Water
    • 1,250kW chilled water process load
    • 1 x Star built water-cooled IW1250LT Indigochiller package unit cooling water to 2.0°C ± 1.0°C. comprising 5 x Danfoss Turbocor centrifugal compressors, 1 x gravity-flooded shell & plate evaporator, 1 x separation vessel & 1 x shell & plate condenser
    • 1 x Star built evaporator pump set comprising inverter driven variable speed run and standby pumps.
    • 1 x Star built condenser pump set comprising fixed speed run and standby pumps.
    • 1 x existing site cooling tower

    Star Refrigeration is the UK’s largest independent industrial refrigeration engineering company. Star focuses on the design, manufacture, installation, commissioning and maintenance of industrial refrigeration systems.

    Star offers a turnkey package to all users of refrigeration plant. Established in Glasgow in 1970, the company provides fast response 24-hour technical support from a network of nine branches to customers throughout the UK.

    Star's technical advisory arm, Star Technical Solutions (STS), operates as an independent consultancy providing advice on refrigeration engineering issues. Star also owns food freezing and chilling equipment specialist Starfrost, as well as mechanical and electrical contractors Penec.


  • Robert Wiseman Dairies


    Star Refrigeration has installed an energy efficient cooling plant for Robert Wiseman Dairies, at its brand new £80million facility in Somerset.

    Star developed the state-of-the-art cooling solution for Robert Wiseman Dairies’ (RWD) new milk production facility in Bridgwater, Somerset. With eight processing dairies nationwide, RWD procures, produces and delivers liquid milk to major multiples and independent retailers throughout Great Britain.

    RWD has a strong record of investing in new facilities to create the UK’s most efficient and environmentally friendly dairies. The company’s new facility in Bridgwater has been designed to produce 500 million litres of milk per year and features a number of innovative technologies to increase energy efficiency and reduce carbon emissions.

    RWD wanted the Bridgwater facility to feature a high efficiency cooling plant, which operated on natural, environmentally conscious refrigerant. Following a competitive tender process, Star worked closely with RWD in a contract valued at over £1.5million.

    Star’s cooling solution for the Bridgwater site comprised a high efficiency process cooling and cold room refrigeration system. The system operates with natural ammonia as the primary refrigerant, cooling a glycol secondary fluid.

    The refrigeration plant has a total cooling capacity of over 3MW covering both process and cold room cooling requirements. In addition, Star’s Envitherm transcritical CO2 heat pump provides high grade heat recovery for office and water cooling.

    Energy efficient design features include inverter driven motors, floating head pressure control, economised screw compressors and heat recovery for warm glycol cooler defrosting. These provide RWD with an annual running cost saving of over £80k, when compared to a typical system design.

    Star Refrigeration Sales Director Rob Lamb says; “The Robert Wiseman Dairies project demonstrates how energy efficiency benefits and running cost savings can be applied to large capacity cooling systems.”

    The refrigeration plant is located on the first floor of an adjacent plant room. The plant layout is carefully designed to minimise footprint but provide sufficient access for equipment servicing.

    The plant features Star built screw compressor packages and surge drum, connected to evaporative condenser and plate heat exchanger evaporators. It also features variable speed process and evaporator pumps, cold room coolers and an Allen Bradley PLC linked to the main dairy control system. Star-owned mechanical and electrical contractor Penec was responsible for site wiring and control panels.

    Star Refrigeration is the UK’s largest independent industrial refrigeration engineering company. Star focuses on the design, manufacture, installation, commissioning and maintenance of industrial refrigeration systems. The company offers a turnkey package to all users of refrigeration plant.

    Star's technical advisory arm, Star Technical Solutions (STS), operates as an independent consultancy providing advice on refrigeration engineering issues. Star also owns food freezing and chilling equipment specialist Starfrost, as well as mechanical and electrical contractors Penec.