Briefs: Largest distribution centre in Africa

The centre, built by Woolworths in Midrand, South Africa has a surface area of 72 000 m². The 2-stage refrigeration system uses 4.2 tons of ammonia. It operates at -9°C/+32°C on the low stage while the high-stage ammonia circuit is used to chill 100 kg/s of propylene glycol from -1°C to -6.5°C using two 1200 kW-capacity plate heat exchangers. Five screw compressors provide the total chilling and freezing capacities and the centre also uses high energy efficient evaporative condensers and polystyrene insulation.