Large Scale Cooling for New Distribution Centre

Services: Refrigeration Design, Plant and Cold Room Supply, Installation and Service & Compliance

Project Overview

Bidfood required a refrigeration solution for their new distribution centre in Chepstow, South Wales.

The site was an existing, un-occupied distribution centre which would be demolished back to its structural steelwork, then rebuilt and refurbished.

Bidfood approached us with a requirement for two very large cold rooms, one to be used as a -25 ⁰C freezer and the other a + 2⁰C chiller.

Thanks to our three decades of experience of delivering refrigeration solutions in industrial environments, we were able to call upon our extensive experience to devise a bespoke solution for Bidfood that met all of their requirements.

Challenges

• The cold rooms were on such a scale that we needed to design a robust solution capable of cooling the required expansive spaces
• We also needed to devise a solution suitable to the irregular layout of both spaces
• The site was an existing distribution centre which was being partially demolished. Because of this, demolition and construction phases took places concurrently. To ensure a smooth installation we built our programme around the demolition programme
• The programme of works was tight and Bidfood were keen to begin using the large cold rooms as soon as possible. We kept the programme on time by closely managing each aspect of the project and communicating updates and any issues arising with Bidfood quickly.

Key Benefits

• A key benefit of the chiller solution was enhanced protection in case of a refrigerant leak. The secondary glycol flow and return chilled water system reduces the refrigerant in the system to the primary side and in turn the refrigerant charge. This reduces the amount of gas that could be released in the event of a leak
• Both the coolers and freezer evaporators were installed on a common system with valve stations, giving individual control of each asset. This gives Bidfood greater control in regulating room temperatures. This is especially important for larger rooms where warm spots occur near doors.

Our Solution 

We designed a complete solution for Bidfood to meet their requirements, which were:

• The installation works needed to be carried out while other parts of the existing site were being demolished
• In line with the bespoke design, we supplied the cold rooms and all associated refrigeration plant, including heating and cooling evaporators, glycol and fluid chillers, compressors and condensers
• The refrigeration solution needed to have a cooling capacity of 360 kW for the freezer and 270 kW for the chiller. Both cold rooms were in the region of 90m wide and between 7.5m and 8.5m high, so the plant selected needed sufficient capacity to cool such large spaces

The freezer plant needed to be split into two identical systems for redundancy and plant failure purposes. The freezer solution was a DX type using refrigerant R407A split into two identical systems. In addition, three Sabroe screw compressors were supplied, selected for their exceptional reliability, low running costs and ease of service. Two of the compressors would be continuously operational with the third acting as a swing machine for greater resilience in the event of a system failure. The heat rejection was accommodated by two air cooled ‘v block’ condensers and eight heating and cooling evaporators were mounted on steel at high level on the rear wall of the cold rooms.

For the chiller, two 150 kW fluid chillers were installed with a hydronic module incorporating a water circulating pump, expansion tank, water flow switch, pressure gauges, purge valve and throttle valve. We also installed eight heating and cooling glycol coolers, mounted on steel at high level and connected to a common glycol flow and return chilled water system. Further cooling was provided by two fluid chillers located externally.

The refrigeration solution was completed in five months, alongside other refurbishment works that were taking place at the same time. After successful commissioning and executing performance checks, we handed over the system to Bidfood. On the basis of our performance, we were selected by Bidfood to be their refrigeration service partner to carry out all servicing and compliance checks to keep the systems running efficiently.