Tag Archives: antimony

Red River’s Hillgrove gold op starts ramp-up process

Red River Resources has commenced production at its Hillgrove gold operation in New South Wales, Australia, and is now ramping up to the plant’s 250,000 t/y capacity.

Gold processing follows the delivery of first ore to the Hillgrove run of mine pad on December 23 from Bakers Creek stockpile mining and trucking activities. This ore was processed by the plant on December 29.

Hillgrove, about 30 km from Armidale in New South Wales, is a past producing mine that was placed on care and maintenance in 2016 due to low prevailing antimony prices.

Prior to recommencement of mining, Hillgrove produced more than 730,000 oz of gold (in bullion and concentrates), more than 50,000 t of antimony (as metal and in concentrates), plus material amounts of by-product tungsten (in concentrates).

It has a JORC 2012 resource of 5 Mt at 4.3 g/t Au and 1.5% Sb for 692,000 oz of gold and 75,000 t of antimony. This resource is contained within six key hubs in the Hillgrove Mineral Field, with Bakers Creek being both the largest gold production centre in the field and having the deepest workings.

The Hillgrove site includes a 250,000 t/y processing plant, which comprises a selective flotation circuit (capable of producing antimony-gold and refractory gold concentrates), an antimony leach/EW/refining and casting plant, a gold cyanide leach circuit and gold room, plus a pressure oxidation circuit.

The site also has a high-density polyethylene lined tailings storage facility, which was constructed in 2006 and has about two years of production storage capacity.

All of Hillgrove’s electricity requirements are sourced from a 66 kVa grid-connected power supply from Ergon Energy with 11 kVa site power reticulation. Water is sourced from storage dams and underground workings.

Hillgrove has all the office facilities required for operations, including an administration office, mining operations offices, maintenance offices, workshops (heavy vehicle, light vehicle and boilermaker’s workshops), process plant offices, metallurgical laboratory building and first aid building, the company says.

Clean TeQ DESALX plant up and running at Kirkland Lake’s Fosterville gold mine

Clean TeQ Holdings Limited has formally handed over a Continuous Ion Exchange Desalination (DESALX®) plant to Kirkland Lake Gold’s Fosterville gold mine in Victoria, Australia.

Clean TeQ says it was engaged to design, supply and commission a two million litre-per-day Clean TeQ DESALX mine water treatment plant, with the plant designed to deliver a sustainable water management solution by treating mine process water.

The plant construction was completed in late 2019, with commissioning and operations commencing in early 2020. Now, Clean TeQ has confirmed the plant has passed the performance tests specified in the engineering, procurement and construction contract and the customer has issued a formal notice of acceptance and completion, it said.

Sam Riggall, Clean TeQ CEO, said: “After successfully demonstrating the world’s first ever commercial scale CIF plant in Oman late last year, this is yet another moment of great significance for Clean TeQ.

“Confirmation of the successful deployment of our innovative DESALX solution for this application, designed and delivered by Clean TeQ, is strong validation of our proprietary continuous ion exchange technology, and provides us with a firm foothold in the mining waste water treatment market from which we can continue to grow the business.”

The DESALX technology consists of two continuous ionic filtration (CIF®) modules in series removing divalent cations and anions present in the water through complementary processes. The modules contain ion exchange resins that are cycled between columns using air lifts, allowing for continuous operation and regeneration of the system. This system increases impurity removal efficiency, reduces chemical use, and provides protection against fouling, according to Clean TeQ.

The DESALX solution is well suited to purification of difficult to treat waste waters with high hardness, sulphate, and heavy metals as well as suspended solids which can foul reverse osmosis membranes. These types of waste waters are common in the mining industry, including acid mine drainage water, the company explained.

At Fosterville, the equipment provided by Clean TeQ includes a precipitation package to remove antimony and arsenic. The effluent from the clarifiers is treated by the DESALX plant to remove sulphate, calcium and magnesium with gypsum as the only by-product. The DESALX effluent is then further treated by reverse osmosis to produce water for re-use.

“The Clean TeQ system is a key enabling component of the customer’s overall water management strategy which includes a medium-term target of creating a true ‘zero liquid discharge’ solution that does not produce any saline brine and includes aquifer reinjection,” Clean TeQ said.

Clean TeQ Water is now focused on completing one additional key project at a copper-cobalt mine in the Democratic Republic of the Congo, and a number of pilot programs in China.

“This Clean TeQ system, as well as the plants recently completed in Oman and Australia, are the first of their type anywhere in the world and have been deployed as part of three different technical solutions,” the company said. “The successful delivery and commissioning of these plants provides strong demonstration of the efficacy of Clean TeQ’s suite of proprietary ion exchange technologies and their versatility for metal extraction and wastewater treatment. As commercial scale plants, the facilities provide a valuable platform from which to now rapidly grow Clean TeQ Water.”

Costerfield gold-antimony mine firing on all cylinders thanks to RCT solution

Removing personnel from underground loading operations at Mandalay Resources’ Costerfield gold-antimony mine in Victoria, Australia, through RCT’s ControlMaster® Teleremote and Guidance Automation, has led to time and cost savings, as well as maintenance and safety benefits, according to a recent case study from the automation specialist.

Costerfield produces ore via a single portal underground mine with narrow vein mining carried out to extract vertical veins of ore. The mine produces up to 80,000 gold-antimony-equivalent ounces per year in a concentrate comprising around 54% antimony and 60 g/t gold.

The nature of narrow vein mining dictates that ore drives are quite thin to reduce the amount of waste material that is captured, with Costerfield’s drilling and blasting program designed to maximise ore recovery by throwing the ore towards the draw point. Historically, however, the site could only recover 75% of the ore, according to RCT, due to the remaining ore sitting in the stope void out of reach of the underground LHD as manually operated loaders could not exceed the stope brow.

Looking to increase productivity, Mandalay investigated implementing a loader that could be managed remotely to extract additional ore and to safeguard equipment operators from hazardous situations at the mine face. This led to it, in 2015, engaging RCT to implement its ControlMaster Teleremote and Guidance Automation product on a Sandvik LH203 LHD.

The automated loader enabled Mandalay Resources to retrieve significant amounts of ore that were previously unreachable, RCT said.

In recent years RCT has increased the autonomous fleet at Costerfield by commissioning ControlMaster Teleremote and Guidance Automation on a second Sandvik LH203 as well as a Sandvik LH151D.

The machines are managed from Fibre Optic Control Stations at secure locations in the underground mine protected by Laser Guard Containment Units as well as stations on the mine’s surface.

Jayson Guzzo, Major Projects and Innovation Manager – Costerfield, Mandalay Resources, said removing operators from the machine is the “best outcome” as it eliminates their exposure from one of the highest risk jobs, which is working at a stope brow.

“The small loaders we use are very rigid which has the potential for repetitive strain injuries,” he said. “They also have open cabs and, in this environment, dust, machine exhaust and debris can be an added safety concern.”

In mid-2019, Mandalay made the decision to implement a digital mine communications network to accommodate future technological growth.

Guzzo said: “Given that we are a narrow vein operation we may have to access ore a significant distance from the mine access point so we are looking at going to a digital platform so we can run a fibre backbone and autonomously operate machines over a vast distance.

“In a traditional mine, you might spend a whole week bogging a single stope before moving, but at Costerfield we might bog three or four headings in one shift, so the number of sites that we have to have set up at any one time are multiple, hence a digital system will significantly speed up the process of commissioning new drives.”

Mandalay has reported that ControlMaster Guidance Automation enabled them to carry out bogging and firing operations simultaneously, saving them substantial time which was previously spent clearing personnel to a safe distance, RCT said.

Guzzo said the solution has enabled the company to reduce shift changeover time by two thirds – which is a significant cost saving – and the site has also experienced less unplanned machine downtime.

“At Costerfield, the drives are roughly 2 m wide so Guidance Automation keeps the machines off the walls and stops them bouncing around the tunnels, so the damage to the machines is a lot less and results in significantly reduced unplanned maintenance time,” he said.

Guzzo concluded: “Relocating operators from the cab of our loaders to safer environments on the mine’s surface is essential and being able to continue bogging during firing as well as significantly reducing shift changeover time is critical to improving site productivity.

“Plant automation is definitely the way of the future in the mining industry and RCT are the leaders in that area, which is why they are our preferred supplier with this equipment.”