Rio Tinto’s Yandicoogina Mine site located in Western Australia’s Pilbara region approached Thermal Engineering to upgrade the 3 existing Chiller units that were servicing the tertiary crushing units with 3 new Chillers as well as 2 additional units for an expansion.
The existing units provided 15 years prior by Thermal Engineering required an upgrade to allow for increased production capacity. The new units provided were designed to provide 150kW of cooling at a remarkable design ambient temperature of 50°C.
The control panel featured an IP66 rating, essential when installed close to crushing circuits, combined with sun shades on all sides to protect the switchgear from the harsh Pilbara sun. Long distances for communications required the controls to be compatible with fibre optic. Remote fault resets and run signals combined with the ability to have a hardwired enable gave these units the ability to continue running even if communications were interrupted. It was critical for site technicians to be able to monitor the equipment as well so a 10” touch screen HMI was installed that allowed information to be easily located and observed. With multi-level password protected access it was an ideal solution to protect the unit from unauthorised changes yet still allow qualified technicians to complete required maintenance and monitor faults.
Cooling requirements provided indicated that process cooling water at 27°C would need to be provided to the crusher lube pack to cool the oil to the required temperature resulting in a return of 33°C water to the chiller. This information combined with flowrate data influenced the selection of a stainless-steel plate heat exchanger capable of providing the 150kw cooling requirement.
