Many hydrometallurgy plants that employ solvent extraction (SX) as an upgrading and purification step, have to contend with the formation of crud within the SX circuit. Effective management of crud is essential to prevent build-up in the settlers and the adverse effects on metal recoveries. ProProcess’ integrated Crud Forx™ system is a solids removal solution designed for the online removal of bottom solids from SX settlers.

The compact system comprises a multi-piped slurry suction head, which is partially or fully immersed in the SX settler. The slurry suction head can either be connected directly to a removable flexible hose coupling to remove solids from the sides of a settler, or to one or more modular lengths of rigid transfer piping to access areas further within the body of the settler for removal of solids.

A study conducted at Glencore’s Mutanda site in 2014 showed that due to a change in solids throughput in their leaching section, the total suspended solids (TSS) entering the SX circuits via the PLS increased. These solids deposited in the refineries SX settlers. The Crud Forx system was then employed from March of the same year and a copper mass transfer improvement of 7.8% to 16.2% was realised in respective SX circuits. Mutanda’s copper production rate was stated as 200,000 t/y. At an average copper price of $3/kg this translates to a saving >$46 million in copper annually.

Jinchuan’s Ruashi Mining SX circuits also experienced high levels of TSS, which were mainly attributed to the talc content of the ore. The primary operational challenge experienced by their SX operators was related to impurity transfer. The Crud Forx was used in one of the HG SX settlers and a reduction of >50% in organic-to-aqueous entrainment in the raffinate was realised after using the technology for a 24 hour period. Not only are operational costs reduced by optimising reagent usage, the fire risk posed by preventing the organic from reporting to other circuits (especially electrowinning) are minimised.

At First Quantum’s Cobre Las Cruces copper mine in Spain, the PLS stream contains saturated levels of calcium, resulting in gypsum precipitation in the SX circuits. The application utilises deep settlers that result in deep, high density, compact SX bottom solids. The Crud Forx in these applications requires start-up assistance to create a crater in the SX bottom solids bed. This allows an adequate amount of the aqueous phase to dilute the solids and thus alter the density in such a manner that the solids can be mobilised. This was achieved by implementing the Crud Forx system in conjunction with a standard diaphragm pump crud removal. Once the crud bed in the Cobre Las Cruces settlers was initially disturbed, the crud removal from one settler occurred within three hours.

In each of the trials the Crud Forx proved to be successful in its application, and has since been deployed to many other refineries using SX technology by ProProcess, who have been granted the legal rights to this technology, developed and patented by Darren Megaw.

MACA Interquip has been awarded a A$39.7 million ($26.3 million) engineering, procurement and construction (EPC) contract for the refurbishment of the Three Mile Hill (TMH) processing plant at the Coolgardie gold project, in Western Australia.

Focus Minerals, the owner of the project, paused production in 2013 in response to lower gold prices to concentrate on the exploration of the wider Coolgardie area, yet, with operations now resuming, MACA Interquip is scheduled to reach commissioning of the refurbished plant by mid-2023.

MACA General Manager, Ben Thomas, said the MACA Interquip team have begun site works with the construction team ramping up throughout November. “The TMH plant will be refurbished to safely operate at its original nameplate of 120,000 tonnes per annum. We look forward to delivering value for our client, Focus Minerals.”

Focus issued a new life of mine plan for the Coolgardie gold project, in October, outlining a plan to produce 402,000 oz of gold over a seven-year mine life.

GHH is not in the business of forcing its customers to move in one direction or another; it is focused on delivering solutions that work for operators and mine sites today while offering options for what may come tomorrow.

The Schmidt Kranz Group-owned company has made a habit of supplying market niches across the globe, creating machines for the low-profile mines of southern Africa or narrow-vein operations in Latin America.

It has done this while retaining a key focus on the soft-rock sector in its German homeland – one dominated by a major salt and potash player.

Now, having assembled an impressive line-up of new machines over the last three-or-so-years and re-birthing a 10-t loader that the company expects to garner appeal across some major mining markets, GHH is out to claim more significant hard-rock mining share than it has in the past.

“Solid as a rock” is not just a catchy tagline the company attaches to its logo; it is also representative of the GHH machine point of difference.

“Robust, durable and reliable” are the three standout qualities the company highlighted at its most recent product launch in Gelsenkirchen, Germany. One can add to these traits an in-cab operator focus that isn’t always top priority for its fellow OEMs.

The latter element is reflective of the types of customers GHH has traditionally served in the mining space, as well as the need to treat operators with the respect they deserve – especially when there is less of them available to service mining operations in line with the global skills shortage.

The robustness and durability are easy elements to unpick given the company’s standard operating procedure for underground loaders is to allow them to run for 20,000 hours, carry out a machine re-build and let them work for another 15,000 hours thereafter, Ingo Rath, Product Manager for Loaders at GHH, explained.

“In fact, we sometimes have machines that are re-built a third or a fourth time and continue to operate in the field,” he told IM, emphasising this durability.

The reliability benefit is tied to the company’s careful engineering and design, aiming to remove unnecessary electronics that can lead to machine downtime and focusing on hydraulics wherever possible.

Some of the only electronics on-board your average GHH machine are specifically designed to improve uptime.

Take GHH inSiTE, for instance, a condition monitoring solution operating around the globe. This platform – in simplified terms – highlights potential issues that could lead to time in the workshop, while also reporting on individual machine performance.

On top of this, the company can provide real-time brake wear via sensor-based solutions. This is a critical element for both safety and maintenance.

It is not only the sparing use of electronics that bolsters GHH machine uptime.

Take the company’s tethered loaders as an example. Here, the company has designed the cable reel to be carefully distributed and retracted via a vertical coiling mechanism, as opposed to the horizontal equivalent some other manufacturers have elected to use.

This allows the company to offer cables up to 250-300 m in length that have drastically improved cable life, according to Jan Petzold, CEO of GHH Group.

“We’ve analysed the two options – vertical and horizontal reel configurations – and see that we can improve the lifetime of the cable more than twice with the vertical reel due to the reduced tension from controlled spooling,” he told IM.

Design for an outcome

The clever design goes beyond the robust, durable and reliable pillars GHH has built its reputation on.

The introduction of z-link kinematics on the body frame of the new LF10-NEO – as well as relocating the steering cylinders – has allowed the company to boast a 10-t-payload loader with the highest tipping height in its class. It is also a full 0.5 m above the tipping height offered by its predecessor, the LF10.

This is a significant point of difference in this popular class of underground loader and one that the company is confident will be appreciated in key markets like Latin America where the machine will be able to three-pass load not only the company’s MK-30 truck (to be launched next year), but also any other 30-t-payload underground truck on the market.

While the company has earned a reputation for delivering machines tailored to the application, it has also been attempting to incorporate more modular design into its newest models to improve maintenance times and reduce assembly durations.

The LF10-NEO, for instance, has the same cab as the larger LF14. It also has left- and right-hand saddles that are bolted onto the back of the loader and can be removed and replaced if required for underground shaft transport.

Within this modular blueprint, GHH is also able to offer a choice of engines on the same block from Volvo Penta or Mercedes for the LF10-NEO, ranging from EU Stage 3, to US Tier 4 Final and EU Stage 5.

This modularity is enabling the company to turn around machines quicker, which proves highly valuable when bidding on contracts from new hard-rock mining clients.

All the while, the company can design a tailored machine for a specific application should the right client come knocking. This was displayed when touring the factory in Gelsenkirchen, where a low-profile SLP-14E tethered electric machine was in the shop awaiting final build and factory acceptance testing.

This machine, like others in the company’s range, came about from collaboration with one of its key strategic customers in the underground mining space.

Pull, not push

GHH is focused on reducing engineering and maintenance complexity on its machines for its clients, but also wants to offer advanced options to those further down the road on their digitalisation and automation initiatives.

Thanks to the help of Schmidt Kranz Group company, Nerospec SK, the company provides an interface to be able to bolt on Level-9 compliant collision avoidance systems to any machine. This, according to Harald Bornebroek, Business Development Manager at Nerospec, represents the first level of automation, with the neroHUB on board these machines able to automatically take over the braking function should an impending accident arise.

The company is also able to offer OEM-agnostic teleremote applications where machines are operating in particularly dangerous areas of a mine – where high seismicity has been observed as an example – but it can also help fully automate loading or haulage operations.

Eric Pohlmann, CEO of Nerospec, highlighted two such applications in Germany – one at an underground salt mine in Germany where a GHH loader is dumping into a crusher and one at a quarry involving a fully-autonomous load and haul pairing from the Germany-based OEM.

And, on the topic of automation, GHH can also claim a world first, having, with the help of the University of Chile’s Advanced Mining Technology Center, run a loading operation at a room and pillar mine without any human interaction in the South American country.

The difference between GHH and most of the other OEMs it is competing with is that GHH is not actively ‘pushing’ these solutions on clients. It is reacting to their evolving needs.

Petzold brought up an excellent example of this when questioned about if the company will create a battery-electric loading and haulage line-up in the future.

To this point, the company only has one machine, the LF19-EB, that has a battery on-board. The battery, however, is used solely for relocating the machine between one loading area and another. Most tasks are carried out with the machine tethered to the existing mine power network via a cable.

This machine has been performing well for one of GHH’s key soft-rock customers and, recently, has come to the attention of one of Europe’s biggest underground hard-rock mining companies – interest that could soon result in a machine order.y

For Petzold, this is a much more realistic way of introducing electrification to the underground sector, allowing mine operations to utilise existing power infrastructure as opposed to forcing them into a major redesign.

“While battery-electric loaders may have their application, the need to recharge a whole fleet of them and put extra pressure on the grid means most operations will not be able to support them with their existing power infrastructure,” he said. “With more flexible cable-electric solutions, like that offered with the LF19-EB, this is not an issue.”

Petzold added that higher diesel prices, on top of the need to decarbonise operations, will lead more mining companies to look at these ‘entry-level’ cable-electric solutions sooner rather than later.

For the time being, GHH Group is happy to stick with this philosophy knowing the niche it is mining in the sector continues to make it stand out for all the right reasons.

Martin Engineering has announced a factory-direct replacement program to deliver freshly-moulded polyurethane cleaner blades for conveyor belts.

Custom fitted on-site and installed free of charge, customers pay only for the replacement blades.

The program from Martin Engineering assures customers of accurately sized and professionally installed replacement blades that are matched to their specific application, providing optimum cleaning performance and service life to minimise the cost of ownership, the company says.

It explained: “Manufactured in-house for the highest quality assurance, Martin’s replacement blades are made with specially formulated, colour-coded urethane to suit virtually any application. The blades have up to 53% more urethane in the wearable area than competitive designs, extending equipment life and durability. To achieve consistent cleaning throughout all stages of blade life, Martin’s patented Constant Angle Radial Pressure technology incorporates a specially engineered curved blade to maintain optimum cleaning performance and efficiency.”

Martin Engineering says it is the only belt cleaner supplier that has designed its own equipment to manufacture moulded blades. This system maximises quality control and eliminates shipping and labour costs by having the new blades delivered and installed direct from the factory.

The company explained: “The need for conveyor belt cleaning is well established, delivering long-term benefits in both safety and production. Properly maintained belt cleaners reduce the accumulation of carryback under the conveyor and minimise dust build up on rollers and other components. Excessive dust and spillage can foul rolling components and cause abrasion on the belt, reducing the life of equipment by as much as 30%. Even though a multiple-cleaner system can be abrasive when in contact with the belt, it contributes less than 5% to the overall belt wear, delivering a significant net benefit.”

While the progress of SANY and XCMG with the supply of battery wide body mining trucks has been well publicised recently, both for Chinese customers but also export customers like Vale and CSN in Brazil, Yutong in Zhengzhou, Henan Province is an increasingly important player. The group told IM that it has trials ongoing with its battery trucks in Thailand, Chile, Indonesia and Kazakhstan, plus estimates its share of the Chinese BEV wide body truck market at 50%. Therefore taking its installed fleet as a whole it is one of the most significant OEMs today contributing to Scope 1 emissions reduction at minesites.

It argues that its market differentiators include having battery mining truck models going back to 2008, therefore having 15 years of practical customer experience and products which are more mature. It also has several established models – its battery trucks including 60 t (YKY90E), 70 t (YKT105E) and 80 t (YKT115E) models. The company says its can offer either fixed chargers or battery swapping to mining customers. On sales and service in some locations it is using its own direct after sales team but follows up with establishment of a full local subsidiary and/or local distributor.

But the underlying strength is its global importance in supplying the BEV bus market. Yutong started electric technology development for buses back in 1999 and today there are more than 170,000 battery buses and other battery vehicles in China and overseas markets; this includes 888 battery buses and other vehicles operating in Qatar for FIFA during the World Cup.

To give some important domestic mining project examples, earlier this year after two months of trial operation in 5,200 m-altitude Huatailong copper-gold mining area in Tibet, Pizu Group decided to purchase a large fleet Yutong BEV mining trucks. Also in Tibet, Zijin Mining’s world class Julong copper mine has used Yutong BEVs in development works, again at well over 5,000 m. In coal mining, customers include Mongolia Energy Corporation while it also supplies BEV trucks to the limestone mining operations of some of China’s leading cement producers such as China United Cement Corporation (CUCC), China National Building Material Group (CNBM) and Esheng Group. Another major customer is bauxite and alumina group East Hope Group.

A notable new export market is Chile – SQM has deployed a Yutong 28 t ZKH5310ZLJP6BEV with a 422 kWh battery pack. With a range of up to 200 km and 28 t of capacity, Chile’s first electric mining truck will be used at SQM’s operations in the Antofagasta Region. In collaboration with the mining company, project partner Enel X is also installing a high capacity charging station unlike any other in Chile.

The new E-truck is expected to make 86 km trips from the Coya Sur potassium nitrate plant in María Elena to the port of Tocopilla, travelling an estimated 7,500 km per month. The production system at Coya Sur uses intermediary salts of sodium nitrate taken from Nueva Victoria, and potassium chloride from the Atacama salt flats. Enel X and SQM developed a leasing model for the purchase of the electric truck and the installation of a 150 kW charging station that can fully charge the truck’s battery in three hours. The charging infrastructure will be installed at the Coya Sur plant in María Elena, guaranteeing almost 200 km of operation.

If the project is successful, the companies will add the Salar de Atacama-Carmen Lithium Chemical Plant route to the initiative. This is the highest traffic route for the lithium process, with 230 trucks in service. SQM work sites could replace 320 high-capacity diesel trucks with electric vehicles, 90 of which are used on the same route as the first truck, over a five-year period.

Engineering firm Worley has been awarded a contract for program management services and engineering, procurement and construction management (EPCM) to support Anglo American’s Woodsmith project in the UK, the mining company has confirmed.

Worley, in tandem with other contractors, is being tasked with delivering a polyhalite mine for its client Anglo American.

The project includes the sinking of production and service shafts with 6.75-m diameters – having depths of 1,594 m and 1,565 m, respectively – and a 37-km-long concrete-lined tunnel containing a conveyor belt, which transports the polyhalite ore from Woodsmith mine, near Whitby, to the Mineral Handling Facility, on Teesside, for processing and shipping.

In Anglo American’s half-year results, released earlier this year, the company outlined that major critical path components had continued to progress to its updated plan at Woodsmith.

“[Our] ongoing technical review confirmed there are several improvements to modify design to bring it up to Anglo American’s safety and operating integrity standards and optimise value for the long term,” it said.

Mining companies around the world rely on Kal Tire’s Mining Tire Group for mining tyre management and supply. Over the last five decades, Kal Tire has grown to a team of more than 2,700 people serving more than 150 mine sites across five continents. With that breadth of expertise across commodities and conditions, and innovation in tooling, processes and safety, Kal Tire focuses on helping customers achieve their goals and maximise their tyre investment. By investing in tyre management technology, sustainable solutions and highly skilled teams, Kal Tire helps solve miners’ evolving challenges and provides measurable value at every stage of tyre life. Some unique Kal Tire solutions making an impact include its Tire Operations Management System (TOMS), Ultra Repair, a thermal conversion recycling facility, six world-class retreading facilities, and a new Maple Program and verified carbon calculator so customers can earn recognition for the emissions saved by retreading.

MTGMarketing@kaltire.com

1540 Kalamalka Lake Road, Vernon BC V1T 6V2 Canada

Solving the environmental challenge of scrap mining tyres

Kal Tire’s Mining Tire Group has a new partner to help scale and grow access to its
thermal conversion recycling technology. How can mines best prepare for a new way of handling end-of-life tyres?

Several years ago, Kal Tire’s Mining Tire Group began to imagine a new way to recycle ultra-class tyres that would lead to the best and highest use of a recycled rubber product. Today, Kal Tire’s thermal conversion recycling facility in Antofagasta can process five 63 inch tyres (20,000 kg) every day – creating 6,500 litres of alternative fuel, 4,000 kg of steel and 8,000 kg of carbon black as well as enough synthetic gas to fuel the plant itself for seven hours.

It’s the only operating facility of its kind that Kal Tire is aware of and, now that it’s been operating successfully for a year, the company was ready to embark on a partnership to scale the solution and reach many more mines much more quickly. In September, Kal Tire and Mitsui & Co., a global corporate group focusing on innovation and sustainability, announced a joint venture that will support growing demand for OTR recycling solutions, and the collaboration will start by commercialising the Chilean plant in 2023.

How did Kal Tire develop this unique technology at the top of the recycling hierarchy and what does the new partnership mean for the mining industry? At a time when mining companies are pursuing ESG and sustainability solutions with greater attention than ever, why is thermal conversion a much-discussed option and what can mines that are determined to reduce their carbon footprint learn about paving the way for bold solutions?

Until recently, Chile was like most mining countries in that it was without a viable option for its stockpiles of scrap tyres. Chile is home to six of the 10 largest copper mines in the world and nearly 500,000 t of scrap tyres. Recognising the need for a solution was great, several years ago Chile became one of the first countries to develop mining tyre disposal legislation.

At the same time, Kal Tire began to consider its role in providing a solution to customers at every stage in the life of a mining tyre, and the company could see the demand for a sustainable solution on the horizon. A project team was tasked with exploring not just a practical way to recycle ultra-class tyres (tyres can weigh 4 t and many mines are far from major centres) but also the most sustainable way to recycle tyres – an option that could do more for mines and communities than traditional shredding. While shredding gives a second life to recycled rubber crumb as garden mulch, asphalt aggregate and playground surfaces, that recycled rubber product will eventually end up at the landfill. The phrase ‘circular economy’ was less common then, and it was one the project team aspired to achieve.

Kal Tire has been serving customers in Chile for decades, and so the legislation discussions became the impetus for Kal Tire to develop a mining tyre recycling solution that would first be implemented in northern Chile.

Significant research led the project team to thermal conversion recycling. It’s a unique process that uses heat and friction to induce a reaction that converts tyres to their base elements. After the tyres are cut into smaller pieces, they’re heated in a vacuum with no oxygen. That also means there’s no combustion and no smoke – a very clean, environmentally friendly process. After about five hours in the reactor, the process emits a gas that fuels the entire process. The external fuel is turned off and the tyres themselves provide the energy for the process to continue.

When the process has completed, what’s left is carbon black, alternative fuel and steel – the original components used to manufacture a tyre, and virtually 100% of the tyre can be reused as high value chemical feedstock. Carbon black can be reused in batteries, plastics, pigments and paints. High quality tensile steel can be recycled in numerous ways. Oil can fuel generators, or it can be refined into alternative fuel for reuse in mine site equipment – creating that circular economy and a greater impact.

Back in 2015, however, the technology didn’t exist to support the recycling of mining tyres. If Kal Tire wanted to pursue thermal conversion, it would have to develop the technology.

What followed was the arduous process of making thermal conversion a viable and effective solution for ultra-class tyres and building the 20,000 sq.m facility in the heart of Chile’s mining region. During that process, Kal Tire was also participating in dozens of conversations with customers and the Chilean government to ensure the plant would meet the needs of government and industry, and exceed environmental and safety requirements.

Throughout, Kal Tire commended the leadership of the government and the involvement of the mining industry, keen to operate in a way that’s more environmentally responsible.

A few years later, as the facility’s wet testing approached, one of Kal Tire’s longstanding Chilean customers invested in having 2,300 t of its scrap tyres recycled. In the spring of 2021, the first reactor’s full load tests were successful and, later that year, the facility reached the end of commissioning. The progress followed a groundswell of interest in the mining industry to support a circular economy and ESG, but how would the output quality compare with expectations, and how could Kal Tire share these learnings to help other regions take action?

As Kal Tire begins to recycle some of the thousands of scrap tyres in Chile, the potential opportunities for reuse of the materials are growing, as is the appetite for an approach that creates this kind of circular economy.

Over the last year, the facility has seen consistently high-quality outputs and, with that, more opportunities for them to become high value chemical feedstocks or fuels. For example, the project team imagines a future where the carbon output could be reused in conveyor belts on mine sites (and the belts could be recycled time and again), or in the manufacture of plastic piping that transports water on mine sites. Mines have the potential to use a tyre once for its intended purpose, and then reuse a portion of a tyre’s original material in a form such as fuels. This is the chance to have an even greater impact for customers and communities that Kal Tire sought to achieve.

The technology is effective. The outputs are of high quality. The circularity is proven and exciting. What now? How can this solution be used in other countries?

Many plants have to evaluate whether to do major component replacements in-house or take advantage of OEM service teams to complement their site personnel’s efforts. Baden Parker, Senior Manager, Global Field Services with Metso Outotec, shares his thoughts on what needs to be considered when dealing with these major service events.

When it comes to replacing major components for gyratory, cone and jaw crushers, finding the right personnel who are trained for these specialised tasks can be a challenge. Bottom shells, mainshafts or gears eventually need replacement or even an upgrade to take advantage of product improvements. Large and heavy parts often require specialised handling and installation procedures, as well as specialised tools to ensure safety.

When replacing an eccentric, a pitman, a pinion or any other major crusher component, many questions can come up. Has the site planned this type of work before, and does it have all the right tools? Are all the service steps perfectly understood to do the work safely and efficiently? Are there experienced personnel available to execute the part change-out? Does the site service team know what to look for to make sure the parts come together properly? Are new parts to be used or are the existing parts that are going to be re-used in good condition?

Using in-house expertise, OEM support or both

Many mine sites and plants try to tackle these types of crusher component change-outs with their in-house capabilities. However, even with sites that have strong maintenance teams, there are many challenges that may not be considered. Some sites may have to deal with high turnover in key service positions, leading to uncertainty in how to perform these major and non-routine maintenance tasks. Other plants need to service many models and brands of equipment and may not have the specialised knowledge that comes from performing complicated parts’ change-outs on a regular basis. There is also the constant struggle between production and maintenance aims and goals. When the pressure is on to increase production, there can be the temptation to shortcut maintenance times, which can lead to equipment problems or safety concerns that outweigh the time saved doing the actual work.

Having served at mine sites for 10 years, holding roles such as Shift Mechanical Fitter, Leading Hand, Supervisor, Senior Supervisor & Maintenance Planner before joining Metso Outotec as a crusher maintenance expert, has given me a broad view when it comes to service operations. I gained considerable knowledge on the life cycle of a site’s crushing assets and the maintenance required to ensure equipment reliability and, in turn, plant availability. I can say with confidence that if the on-site crews are well trained, many routine tasks can be handled safely and competently. However, a typical maintenance mentality that I observed (and personally held for some time) is ‘We can fix anything ourselves’ and that calling in the OEM was not needed, as we could work out the best ways of working ourselves. For many routine component replacements, this was indeed true enough.

However, over time I changed my view and realised that, in many cases, OEM support complemented a site team’s strengths and led to a far better result in terms of efficiently maintaining a site’s crushing equipment. I would like to share just a couple of examples that I have seen first-hand, relating to gyratory crusher component replacement work, that display how not pulling in needed know-how can be detrimental and potentially costly.