The Selinsing Gold Sulphide Flotation Plant
During 2021 and 2022 Monument constructed a new 950,000tpa sulphide processing facility at the Selinsing Gold Mine with a designed capacity of 40-45,000tpa of gold concentrate. Full commercial production began in September 2023.
Pre-existing crushing, milling and gravity circuits from the previous CIL operation have been integrated into the new sulphide operation, and the Selinsing Gold Mine now has new lease of life, with production to continue from the mining and processing of ‘refractory’ sulphide ore, producing a gold concentrate for sale to third parties.
The sulphide flotation plant comprises a trash screen, two conditioning tanks and six rougher tank cells followed by three stages of cleaner flotation. Various reagents are added during the flotation process: soda ash as pH modifier, sodium sulphide as sulphidiser, copper sulphate as activator, carboxymethyl cellulose (CMC) as slimes depressant, potassium amyl xanthate (PAX) as collector and methyl isobutyl carbinol (MIBC) as frother.
Final flotation concentrate is transferred to a 9m diameter concentrate thickener from which thickened slurry is pumped to the concentrate filtration plant. Final flotation tailings are transferred to a 14m diameter water recovery thickener and thickened slurry is pumped to the tailings storage facility (TSF) while the supernatant water overflows to the process water tank.
The thickened slurry is stored in a concentrate storage tank prior being pumped to the concentrate filter press. The concentrate filter removes 85% to 90% of the water from the thickened slurry to produce gold concentrate cake that has moisture content of 10% to 15%.
The gold concentrate produced is transported by tipper truck and shipping container to the loading port and subsequently shipped to the destination port depending on the concentrate buyer.
Inferred Resource Potential Opportunity
The opportunity to include Inferred Resources totaling 150koz was discussed in the 2019 Feasibility Study (NI 43-101 Technical Report - Selinsing Gold Sulphide Project, Malaysia). The Inferred Mineral Resource inside the Reserve open pit designs potentially contains an additional 20koz of gold, while the Inferred Mineral Resource external to the open pit design represents a further 130koz of gold, and importantly the Selinsing Gold Mine has a proven track record in converting oxide Inferred Mineral Resources to recovered ounces.