Chilled and Frozen Distribution Hub

As the first of its kind in the UK for a leading on-line retailer, Space Engineering were tasked with designing and installing the refrigeration equipment for a new £Multimillion, chilled and frozen facility.  As a turn-key project, we were assigned with the provision of the cold store construction, plant, controls, commissioning, and a supporting planned maintenance contract.

With a view on energy efficiency and future proofing of the refrigeration equipment, the best choice was a natural refrigerant – CO₂.

Working with the client on the expected room usage, we were able to calculate the heat loads.  This was then designed to a +35°c outside ambient, with 70% resilience between 2no refrigeration systems.  Each system has multiple compressors to share the running loads.  The Chilled design set point was at +1°c and the freezer design set point at -23°c.

To ensure energy efficiency we included parallel compressors, lead compressor inverters, EC fans, stepper expansion valves.

There was a restriction to the plant area footprint, so it was important to ensure the external equipment design was suitable.  For this reason, a V-block gas cooler was selected.

Environmental aspects had to be considered and overcome.  Noise levels were met, inverters were used for capacity control, future heat reclaim potential was included with a matrix of potential heat output to consider.

Some of the notable design elements of the project were:

• Evaporator structural support design, split in pack/evaporator allocation to ensure full room operation in the event of a single plant failure
• Fire strategy review with door positions worked through and established
• Vertical evaporator pipework tails to limit condensation, EC fans, Freezer evaporator air socks and rear damper for the best possible defrost
• Strategy of positioning Leak detection beacons/sounders and sensor locations to ensure persons and equipment were best protected
• Shared containment co-ordination of refrigeration services with other discipline
• Evaporator valve board drip trays included with connections to drain headers
• Clear access locations and route highlighted above cold rooms for service and maintenance
• Internal support with commissioning team providing a ‘commissioning intent’ document covering set points and operation of all equipment

Working to a short time scale and delivering the project during the COVID pandemic, Space delivered on time and on budget.