Three HallScrew compressor packages are the driving force behind a state of the art refrigeration system at a new multi-million pound distribution centre run by Wm Morrison Supermarkets PLC at Sittingbourne, Kent. The 1.2 megawatt HallScrew compressors are employed to maintain a constant temperature throughout a large chill store, handling goods for transportation to Morrison’s outlets across the south east. The retail giant was impressed by the ammonia-based system, with its zero ozone depletion properties, and J & E Halls’ ability to design and project manage the installation of ultra efficient refrigeration systems on a large scale.
Wm Morrison Supermarkets have placed the environment at the heart of the design – with their overall corporate social responsibility programme in mind – at this their most environmentally friendly distribution centre. The 920,000 sq ft site will save 17,000 tonnes of CO2 emissions per year.
The refrigerated areas are divided into two parts. A 105,000 sq ft chilled warehouse requires a constant temperature of 1oC, and a 90,500 sq ft produce warehouse needs a constant temperature of 6oC. The chilled warehouse handles dairy produce, fish and meat, while the produce warehouse is responsible for storing soft products like fruit and vegetables.
J & E Hall regional sales manager Duncan Aspinall explained: “J & E Hall is used to tackling jobs of this size and we have been involved in designing and fitting out refrigerated stores for a considerable number of years. Having the know-how to tackle these projects from start to finish is very much a plus point. Inside the cold store, some of the pipe runs go to 200 metres but installation was simplified by fixing all the pipe work and 20 air coolers to a common wall running between the chilled warehouse and the produce warehouse."
“The plant room is situated externally, providing a safe location for the ammonia, while food grade glycol, a secondary refrigerant, is used in all parts of the system internally. Ammonia was the right choice for the job. It is a safe, efficient natural refrigerant with no ozone depletion properties.”
The air coolers are placed at a high level above the floor space. With all the equipment installed on one wall, Halls’ efficient design ensured that the need for access platforms and ladders was kept to a minimum and did not impinge on the floor space.
Of the three Hallscrew 2000 Compressor Packages installed at the centre, two are working full-time with one on permanent standby.
Another key aspect of the project was the expertise shown by J & E Hall in installing the insulated walls and ceilings. Duncan Aspinall explained: “As it is such a tall building we needed the insulation panels to reach as high as 15 metres but we needed wall panels that could be supplied complete and ready to fit. This required special attention to the design and handling of the panels at all stages of the installation.
Monitoring Halls’ refrigeration system could not be more comprehensive, with a SCADA control and monitoring system providing full graphic displays which can be accessed via a lap-top computer or mobile telephone anywhere in the world if required.
The design and onsite installation of the chilled stores was managed by J & E Hall’s Leeds office. Wm Morrison Supermarkets are delighted with the outcome, as the company’s project manager Keith Atkinson explained: “Considering the amount of work that J & E Hall were required to complete, including the refrigeration plant, insulated wall and ceiling panels, we are very impressed to see everything complete and operational on the required date. We are very grateful to the J & E Hall site team.”
