RACA Journal June 2019 | Page 44

Projects 1 Founded in 2004, Chilleweni’s family-run company focuses on providing storage and logistics services to a wide range of clients within the frozen food market. Their impressive new facility is situated in Gosforth Park in Germiston, Johannesburg. PROJECT SCOPE The cold rooms supplied for the cold storage facility were: • 3 x -22°C holding freezers • 1 x 5°C chiller • 1 x 10°C receiving and dispatch area 2 During the negotiations it was decided to remove the designated room for the blast freezers and incorporate five blast freezing sections inside the one holding freezer, by boxing off a section at the bottom of the racking with a plenum for a fan and canvas on the sides to direct the cold air over the pallets. REFRIGERATION PROJECT 3 4 MRE was appointed as the refrigeration contractor in March 2018 after the tender phase was completed and adjudicated. The project was commissioned in September 2018. The plant room equipment included: • 1 x low-stage Mycom screw compressor; • 1 x low-stage Mycom reciprocating compressor; • 1 x swing Mycom screw compressor; • 1 x high-stage Mycom screw compressor; • -32°C accumulator vessel with 2 x hermetic ammonia pumps; • -5°C accumulator vessel with 2 x hermetic ammonia pumps; • Liquid receiver; • Hansen air purger; • 2 x Evapco evaporative condensers; • Sondex plate heat exchangers; • Evaporators by HC Heat Exchangers; • PLC for monitoring and control by Carel; • 2 x Southern Pumps glycol pumps; and • 2x Southern Pumps compressor head cooling pumps. PLANT DESIGN PHILOSOPHY The refrigeration plant was designed with operating efficiency and longevity as the primary design considerations. 1. 2. 3. 4. 42 RACA Journal I June 2019 Freezer pods. Mycom high-stage screw compressor in the ammonia plantroom. Mycom low stage screw compressor with Logix micro- processing panel. Receiving and dispatch valve station with hot gas reheat. www.hvacronline.co.za