Cold Link Africa January/February 2019 | Page 38

PROJECT INCORPORATING COLD CHAIN Woolworths Kyalami takes CO 2 to the next level By Commercial Refrigeration Services (CRS) The custom-built, locally manufactured CO 2 refrigeration pack for the Woolworths store in the upmarket Kyalami shopping centre, takes care of the store’s refrigeration and heating needs. F or this project, CRS manufactured a compound (two-stage) trans- critical booster pack with parallel compression. It consists of medium- stage, low-stage, and intermediate- stage racks, which are controlled by individual rack controllers with their own separate suction, operating, and safety set-points. Each medium-temperature cycle consists of three compressors and each low-temperature cycle consists of two compressors. The intermediate temperature cycle also consists of two compressors and share a common discharge line with the medium- temperature rack. The medium- and low-temperature racks share a common liquid line and separate suction lines to accommodate two separate evaporating temperatures; the low-temperature refrigeration discharges into the medium-temperature suction and in this regard, the low-temperature rack is reliant on the medium-temperature rack to maintain the low-temperature compressor’s discharge pressure within the design envelope. The pack is designed to have a plant room evaporator coil to ensure the plant room area is maintained within acceptable ambient temperatures of a maximum of 25°C. Plate heat exchangers are used for heat reclaim; these heat exchangers 1 1. CRS custom-built CO 2 refrigeration packs for this store. 2. The fridges inside the Kyalami Woolworths store, connected to the CO 2 pack for all their refrigeration needs. 3 3. Health and safety regulations are crucial for CO 2 installations. 2 38 www.coldlinkafrica.co.za COLD LINK AFRICA • January/February 2019