Tag Archives: copper processing

Canada invests in clean and green copper hydrometallurgical technology

Natural Resource Canada has set aside funds for a mineral extraction research and development project that, applied at commercial scale, will help reduce emissions and water use while lowering costs for companies, it said.

The project, being carried out by Vancouver’s Jetti Services Canada Inc (Jetti Resources), will develop a more energy-efficient process to extract copper from regular- and lower-grade ores, as well as waste mining materials and tailings, according to the NRC.

Jetti Resources calls itself a technology-driven natural resources company that has developed a novel hydrometallurgical technology to extract metals of value from mineral ores that the mining industry has struggled to process.

“The Jetti technology is especially advantaged for extracting copper from low-grade primary sulphides, the world’s most abundant copper resource,” it said. “The catalytic technology seamlessly integrates with existing heap leaching methods and downstream processing operations.”

According to the company, the technology requires low capital expenditure, operating costs and enables high copper yields. It also has a strong environmental profile, “leading to lower criteria emissions and water usage along with the maximisation of resources at existing copper deposits.”

The NRC, through its C$155 million Clean Growth Program, agreed to invest C$492,500 ($377,261) in the project, while Innovate BC, a Crown corporation that helps accelerate technology commercialisation by supporting startups and developing entrepreneurs in British Columbia, also committed C$150,000 to the project.

Funding for the clean technology project was announced during the 2019 Energy and Mines Ministers’ Conference (EMMC), held in Cranbrook, British Columbia, taking place on July 15-17, where ministers from federal, provincial and territorial governments are meeting under the theme, ‘Competitiveness and Innovation in Canada’s Energy and Mining Sectors.’

The Honourable Amarjeet Sohi, Canada’s Minister of Natural Resources, said: “The Government of Canada continues to invest in projects that are positioning Canada’s mining industry to lead the clean energy future. Through strong government partnerships and a commitment to innovation, we are building the sustainable and competitive mining industry of tomorrow.”

MOD lays out plans for T3 copper-silver project in Botswana

The feasibility study for MOD Resources’ majority-owned T3 copper-silver open-pit project in Botswana has delivered compelling mine economics, in addition to a fleet and flowsheet plan that will interest the major mining original equipment manufacturers.

T3, in the Kalahari Copper Belt, is expected to require $182 million in development capital and deliver a mine able to produce life of mine average production of 28,000 t/y of copper concentrate and 1.1 Moz/y of silver at all-in sustaining costs of $1.56/Ib after deducting silver credits.

The pre-tax net present value (8% discount) for the project came in at $368 million based on a long-term copper price of $3.08/Ib, or $6,791/t.

The current plan would see T3 produce first product in the March quarter of 2021, operating over an 11.5-year mine life.

In terms of the primary loading fleet, the company said this would be made up of a maximum of five hydraulic excavators in the 120-250 t class. This is considered the optimal option that could achieve the required productivity, maintain a degree of selectivity when required and minimise the number of units required for practical separation of loading and hauling units, according to the company.

The ore and waste haulage fleet is expected to consist of 140 t mechanical drive haul trucks capable of direct tipping to the primary crusher.

MOD said there is step change to a lower annualised total material movement (TMM) after year five of operations. A peak TMM of 39 Mt (annualised) is due to be maintained during the first four years of the schedule, requiring 24 trucks and five excavators to ensured continuous ore supply. TMM drops to 6 Mt/y after year six and is generally maintained for the remaining life of mine, it said.

“The mining schedule has been constrained by setting a maximum vertical advance rate of 120 m/y annum to allow sufficient time for dewatering, grade control, drill and blast and load and haul,” the company said, adding that the maximum vertical lag between benches is set at 50 m.

The production schedule achieves the target process plant throughput rates both during ramp-up and during steady state operations of 3.0 Mt/y to 3.2 Mt/y (peak), it said.

The copper recovery plant and associated service facilities will process run of mine (ROM) ore delivered to a single stage primary crusher. The crushed ore will be stockpiled from where it is fed to a two-stage grinding circuit using SAG and ball milling. Copper minerals in the ground ore will be concentrated in a conventional copper flotation circuit, made up of roughing, regrind and a single stage of cleaning. Concentrate from the cleaning stage will be thickened then filtered on site prior to transporting to Walvis Bay, in Namibia. From Walvis Bay, the concentrate will be shipped to third-party smelters.

Tailing from the roughing and cleaning stages will be pumped to the tailings storage facility located south of the proposed mine. The TSF is designed to store approximately 34.4 Mt of conventional thickened tailing – enough for the 11.5 years of the project life.

The process plant is forecast to produce a life of mine annual average copper in concentrate of 28,000 t, with average grades for Cu and Ag of 30.4% and 383g/t, respectively.

The key criteria selected for the plant design are:

  • The mill will process a total of 34.4 Mt of ROM ore for 11.5 years;
  • The annual ROM treatment is 3.0 Mt/y with a peak treatment rate of 3.2 Mt/y, at a primary grind size of 80% passing 180 μm;
  • Design availability of 91.5% with standby equipment in critical areas;
  • Design copper head grade of 1.3%. This head grade allows for grade variation from the life-of-mine average grade of 1.0% Cu;
  • Eighty-fifth percentile of comminution ore properties;
  • Ore specific gravity of 2.8 t/m³;
  • Laboratory rougher flotation residence of six minutes, and cleaner 1 and cleaner 1 scavenger residence time of two minutes and eight minutes, respectively, and;
  • Rougher concentrate mass recovery of 6.2% (w/w) for regrind circuit sizing and final concentrate mass recovery of 3.6% (w/w) for thickener and filter sizing.

FLSmidth to move into ROL copper demonstration mode in 2019

FLSmidth has provided an update on its Rapid Oxidative Leach (ROL) technology at the same time as reporting a boost in revenue and profit for 2018.

Releasing its 2018 annual report, the company said revenue grew by 4% year-on-year to DKK18.75 billion ($2.8 billion) in 2018, with a 13% growth in order intake (DKK19.17 billion) attributed to strong results from its mining division.

Its mining division saw an order intake of DKK12.86 billion, 24% higher than 2017,  driven by growth in copper, while earnings before interest, taxes and amortisation came in at DKK1.19 billion, 18% up on 2017’s result.

Within the annual report, the company provided an update on its ROL technology, a process it first announced the discovery of in May 2015.

“This groundbreaking solution overcomes three major challenges in the mining industry (copper in particular); declining ore grades, increasing levels of arsenic and other impurities, and reduced production from existing solvent extraction and electrowinning facilities due to falling recoveries from heap leach when transitioning from oxide to sulphide ores,” the company said.

FLSmidth said it was currently testing concentrates from several interested copper miners at its pilot plant in Salt Lake City, US (pictured), and at a third-party independent laboratory.

“The purpose of these tests is to establish data for the customers to determine if they would like to move ahead with prefeasibility studies,” FLSmidth explained.

During 2017-2018, the concentrates from one customer were tested and indicated a positive return on investment. “We have agreed with this customer to supply equipment and operate a demonstration-scale ROL process plant at their facility in South America,” FLSmidth said, adding, “this is an important step in scaling up and commercialising the ROL process”.

In addition to copper, the company has tested ROL with refractory gold and it has proven possible to apply the technology in the laboratory to significantly improve gold recovery, it said.

“We are currently working with several gold producers in research and development of this process, with the goal of potentially moving on to pilot scale testing in 2019,” the company concluded.