Cold Link Africa March/April 2019 | Page 22

PROJECT INCORPORATING COLD CHAIN 2 3 4 Plant safety and compliance with international good practices have been applied throughout the plant. A total of 23 CO 2 sensors are installed in the trading area, cold rooms, and plant room with lights indicating green when levels are safe in each area. All piping is labelled to indicate direction of flow and liquid or vapour. The plant room also has an enclosure with pipe stubs for technicians to connect reading equipment to each circuit during maintenance and fault finding. The hybrid gas cooler was supplied by HC Heat and includes four 910mm EC fans, stainless-steel piping, and integrated Carel controls. Water to the hybrid gas cooler is harvested in the basement from the HVAC, cold/ freezer rooms and cabinets, filtered, and then pumped to the roof where it is stored and supplied to the gas cooler as needed. The entire refrigeration system is controlled and monitored by a Carel electronic control network, which means remote monitoring and adjustments can be done 24/7. All evaporators are fitted with Carel electronic stepper expansion valves. Cabinets were supplied by Colcab and installed by Recold. Piping to the shop floor comprises walled copper pipe specially imported by Matador Refrigeration and runs are over 100m each with a vertical lift of approximately 12m; double risers assist with oil return. High-pressure piping to and from the gas cooler are made of 1. Each lead compressor has an ABB VSD to maximise efficiency. The fourth VSD is mounted on the rear side of the rack. 2. The level of CO 2 at each of the 23 sensors can be viewed on the monitor in the plant room. 3. The fourth VSD. 4. Sensors monitor operating parameters and transmit to the plant management system. 5. The cabinets were supplied by Colcab and lined up by Recold. This is the speciality half-height processed meats cabinets. 22 www.coldlinkafrica.co.za schedule 40 stainless steel, and were tungsten inert gas (TIG)-welded and X-rayed to ensure there were no leaks. EFFICIENCY MATTERS The layout of the Centre Point store has been based on maximum efficiency, appealing to the shopper and with least impact on the environment. Features aimed at maximum efficiency include: • High-efficiency Colcab CO 2 evaporator coils in all cabinets; • High-efficiency ebm-papst fans in cabinets; • LED lighting throughout; • Acrylic doors on vertical cabinets; • Manually operated night blinds; • Sliding covers on island freezers; • 4 × 910mm-diameter ebm-papst fans with EC motors on the CO 2 hybrid adiabatic gas cooler; and • ABB variable frequency drive (VFD) on the lead compressor of each circuit. The efficiency is evident from the compact rack and plant room in comparison to the expanse of the store with a trading area 5 1 COLD LINK AFRICA • March/April 2019