For grids which are supported by hydro-electric generation, and as renewable penetration of grids is increasing, using electricity in lieu of on-site combustion supports lower emissions related to minerals processing. Fuel for mining fleets is often a key focus of mines looking to decarbonise, but eliminating fuel use in processing facilities can also be pursued to achieve net zero targets. This case study outlines the design approach for a gold processing facility in British Columbia, Canada, which commenced construction in 2023. The design included electric elution heating, electric kiln and electric smelting, in lieu of the typical use of Natural Gas or Diesel as a heat source. This paper outlines the drivers for selecting electrical equipment in this case. The potential carbon emissions savings achieved per gold oz with this circuit design are presented, compared to a typical design with on-site combustion to provide heat sources for elution, kiln and smelting. The SO2 system also used electric heat and recycled steam rather than fossil fuels for both sulphur melting and pre-heat stages, as well as temporary no-load heat scenarios. This allowed for the entire process facility to have no fossil fuel power used in the entire process. A number of technical challenges were considered during the design to ensure safe and effective responses to electrical outages. These included, Electrical design (conduits), equipment size and layout, and start-up / shut-down philosophy. This paper outlines the process for identifying and mitigating hazards to manage identified risks.  

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