Basil McKinley Consulting and Mayekawa Japan, along with Tri Tech Refrigeration Australia Pty Ltd, were awarded a project to undertake the component selection, installation and commissioning of a new cold storage and distribution centre in Sydney.
The undisclosed client is a large multinational membership-based retailer that wanted to build their own cold storage warehousing and distribution facility. Prior to the new centre, the company relied on a third party cold storage facility for the refrigerated warehousing of chilled (+2 °C) and frozen (-24 °C) product. The new facility employs around 100 people.
The cold storage facility is divided into two areas: the medium temperature chiller and the low temperature freezer. The plant design featured Thermofin’s pumped CO2 evaporators for both the chiller and freezer.
The chiller has a storage volume of 28,975 m³ and operates +2°C, with a total cooling capacity of 708 kW, achieved using eight 88.5 kW Thermofin pumped CO2 (evaporators).
The freezer has a storage volume of 15,119m³ and operates -24°C, with a total cooling capacity of 198 kW, achieved using eight 24.8 kW Thermofin pumped CO2 (evaporators).
The combined total refrigeration capacity of the plant is 908 kW.
The refrigeration system comprises five NewTon refrigeration packages, built by Mayekawa in their Moriya facility, near Tokyo, Japan.
Each NewTon package is a compact refrigeration unit with a semi hermetic ammonia compressor, water-cooled ammonia condenser and ammonia cooled CO2 recondensing heat exchanger.
According to Thermofin, the primary benefit of this configuration is that overall ammonia charge is reduced and confined to the plant room.
“Because CO2 is used as a secondary refrigerant, a further ammonia charge reduction is possible with the added benefit of being oil free as only ammonia compressors are used,” says the company.
“Once reliquidified by the NewTon packages, the CO2 is pumped to the warehouse, and onto the Thermofin CO2 evaporators. Further improvements in defrost reliability and efficiency are achieved by recovering heat rejected from the NewTon packaged into a central glycol circuit which in turn is used to defrost the evaporators.”
Further gains in the evaporators are achieved by using EC fans which improve energy efficiency whilst reducing cost by eliminating the need for fan variable speed drives. Defrosting the glycol with the cold waste heat presented a simple cost-saving solution.
Thermofin is a Germany-based manufacturer of finned heat exchangers. The company offers a product range comprising evaporators, condensers, air coolers, dry coolers and heat exchanger coils in either standard or custom designs.