Mineral processing equipment manufacturer Gekko Systems is finding engineering solutions for remote and environmentally sensitive mining operations with high energy costs.
Ballarat’s Gekko Systems has become a global leader in mineral processing for mining companies by designing, manufacturing, installing and commissioning energy-efficient modular plants and processing equipment.
Michael Trenorden MIEAust, Engineering Manager at Gekko Systems, explained that the company’s approach focuses on minimising the energy needed to process minerals.
By working with the coarsest possible “liberation size” of minerals to achieve gold recoveries, Gekko reduces the energy requirements.
“The company has been founded on a low energy flow sheet,” Trenorden told create.
High gold recoveries typically involve grinding rocks down to a really small size before undergoing a leaching process. The downside of such a process is that it requires a lot of energy, infrastructure and capital costs.
“Gekko found that not all mining companies have the capital, footprint or available power to undertake that recovery process,” Trenorden continued. “Instead, we use an approach called gravity recovery.”
The process keeps the ore as large as possible for as long as possible minimising energy costs.
“By using a Gekko InLine Pressure Jig or other concentrators to take out the gold through gravity recovery, we can minimise or eliminate the grinding and leaching circuits.”
Overall recovery is lower than a traditional fine-grind/cyanide leaching solution.
“However, the reduction in capital cost and the energy required can be significant compared to a traditional cyanide leaching plant,” Trenorden said.
This not only reduces operating costs and energy consumption but also reduces the over-plant footprint, capital cost, installation costs and environmental impacts. This design philosophy helps all parties in the supply chain in their quest to be carbon-neutral by 2030.
Technological solutions
In recent years, Gekko Systems has focused on real-time instrumentation with products such as Carbon Scout, an accurate carbon measurement and assaying system for Carbon-In-Leach (CIL) circuits, developed in collaboration with Curtin University.
Traditional plant monitoring is done by manual sampling and a combination of onsite and offsite analysis — a labour intensive method which delays results by around 12 to 24 hours.
Gekko is also developing another technology in collaboration with the CSIRO called the OLGA (Online Gold Analyser), the first onstream analyser designed to measure gold in slurries and solutions in real-time.
“This was developed along with the Carbon Scout eventually to automatically control gold process circuits,” Trenorden said.
So far, two units have been installed with the most recent at the Goldfields-owned Gruyere Gold Mine in Western Australia.
“OLGA and Carbon Scout units enable plant operators to automatically obtain information, in real time, [about] carbon inventories, gold on carbon and gold in solution,” Trenorden said.
From there, the equipment allows operators to automate carbon transfers, reagent additions and other process changes to ensure that gold solution losses are kept to a minimum.
“This can result in thousands of dollars of extra gold being recovered by simply optimising the plant performance, while also dramatically reducing reagent consumption and energy requirements for carbon regeneration.”
Gekko has also made a large technological investment into environmental technologies and alternative energy initiatives via Gaia EnviroTech.
A sister company to Gekko Systems, Gaia, uses Gekko’s engineering know-how, regional manufacturing and modular systems experience in organic waste and bioenergy solutions, contributing to Gekko’s goal of reducing carbon emissions.
Regional advantage
Trenorden said that advantages to regional manufacturing are found in better work-life balance for employees, as well as stronger community ties.
“By working closely with local and other regional businesses we can ensure our costs are competitive while dramatically reducing our lead times,” he explained. “That’s the major business case for our regional advantage and it works well.”
This regional approach, coupled with bringing engineering expertise to promote a low-energy mindset, forms a crucial part of Gekko’s work.