Wirtgen Group

Kleemann GmbH, manufacturer of mobile crushing and screening plants, and CDE, the wet processing experts, are combining their strengths through a sales cooperation in Germany.

Starting in September, the Kleemann experts at Wirtgen Deutschland Vertriebs- und Service GmbH will assume responsibility for the sales and distribution of selected CDE products in Germany. These include the newly launched ModaLine^TM fast-deploying containerised sand washing solution, the EvoWash^TM sand washing system, the M2500 modular wash plant, the AquaCycle^TM high-rate thickener, and the FreeFlow^TM mobile washing and water recycling system.

Kleemann GmbH, based in Göppingen (southern Germany), is part of the Wirtgen Group and one of the leading manufacturers and experts in the field of mobile crushing and screening. Since its foundation in 1992 in Cookstown, Northern Ireland, CDE has grown to become one of the largest companies in the global wet processing industry.

Customer Benefit: Optimal end-to-end solution from two premium brands
Crushing, screening and wet processing are indispensable components of material processing applications. Wet processing systems are often found both upstream and downstream of crushing and screening plants in applications such as sand and gravel processing, as well as recycling. Through the cooperation, process experts in ‘crushing, screening and washing’ are now coming together. The aim is to provide an optimally coordinated production system that meets technical and economic requirements alike. Customers of both companies will benefit from significant added value, including a single point of contact through Wirtgen Deutschland Vertriebs- und Service GmbH.

„The collaboration with CDE is an important step for Kleemann, as it complements our portfolio perfectly. Wet processing is a central component of modern recycling and mineral processing – and CDE brings not only a high level of expertise but also innovative technologies that perfectly match our standards of quality. This cooperation will strengthen our position as a solution provider,” says Alexander Knam, Managing Director of Kleemann.

CDE’s Founder and Executive Chairman, Tony Convery, added: “Through this cooperation we are combining our respective strengths, CDE’s expertise in materials wet processing with Kleemann’s established market presence and deep understanding of the local market. This collaboration allows us to bring our technologies closer to customers, providing them with local access to wet processing expertise, trusted support and proven solutions for a wide range of applications.”

Further information:
WIRTGEN GROUP
www.wirtgen-group.com

Revitalisation of an Indigenous community in Canada with the aid of advanced Kleemann crushing and screening technology

Within the context of an ongoing infrastructure project, the Garden River First Nation Indigenous community is supplying graded aggregates for the rehabilitation of a 16-kilometre section of Highway 17A. This runs through the reserve and also serves as a bypass for the national Trans-Canada Highway. In order to fulfil demands in terms of tonnage and grain quality, the community has invested in a fleet of Kleemann machines consisting of a MOBICAT MC 110 EVO2 jaw crusher, two MOBICONE MCO 90 EVO2 cone crushers, two MOBISCREEN MSC 953 EVO screening plants and a MOBIBELT stacker. Depending on the final product specifications, the machines work in combination as primary, secondary or tertiary crushing and screening plants.

Aggregate production creates new jobs
Indigenous communities in Canada are vital to the fabric of the nation, preserving Indigenous culture, language and family ties. In some communities, population is dwindling as many band members move to larger centres with more educational opportunities, jobs, and housing. The Garden River 14 reserve region, located around 700 km northwest of Toronto, is known as the Garden River First Nation and has a population of 3,500 band members, just over 1,000 of whom live within the reserve. Of those, 200 are employed by the community itself, 13 of whom are currently employed in the materials processing operation. The aggregates produced are essential for infrastructure construction, and the newly acquired Kleemann plants contribute to the generation of higher revenue and more jobs.

An investment in the future
The resurfacing began in late 2025 and is scheduled for completion in 2028. The project requires close to 100,000 t of aggregate for the base layer, 170,000 t for the subgrade and 100,000 t of asphalt dust and Superpave. The latter is a recently developed, performance-based system for the production of asphalt mixes and selection of suitable road surfacing binders. It is designed to ensure that the paved surface can withstand extreme temperature fluctuations and heavy traffic without any problems. ‘When we became aware that the bypass was going to undergo resurfacing and we were to be partnered into that project, we realised that our old crusher was too outdated and wasn’t capable of producing some of the products like the Superpave,’ recalls Chris Morettin, Business Entities Manager for Garden River First Nation. ‘We needed to replace that model with something brand new that had the capabilities to meet Ontario Ministry of Transportation requirements.’ Morettin and Aggregate Supervisor Travis Belleau decided to invest in a Kleemann plant train. ‘We conducted a financial analysis based on revenues that were going to be generated, and we were able to see that purchasing this equipment would pay for itself over the lifespan of this project,’ says Morettin.

‘Northern Ontario has a lot of hard rock, and the harder the rock, the more damage there is to an impactor. That’s why we typically see a lot of jaw and cone crushers in operation in this region. They’re just more cost effective,’ explains Richard Perzan, Vice President Sales, Construction and Forestry (Central) at Brandt, the local authorised Wirtgen Group dealer in Canada.

Intuitive, safer and versatile
Aside from the low fuel-consumption, Belleau was also particularly impressed by the intuitive operating concept. ‘I haven’t been crushing very long. I found it fairly easy to learn.’ And adds, ‘I think that speaks volumes.’ ‘What I like most is the touch screen, which has tons of information on it. What Belleau also likes is how the touch screen in the SPECTIVE operating concept helps with troubleshooting and fixing problems. ‘Our old machine didn’t have a touch screen, so you would just have to trial-and-error everything. These machines, they can pinpoint what’s wrong, so you’re not just swapping everything out to try and band-aid a problem. You’re able to diagnose it quickly, have the part replaced and then be back up and running as soon as possible. That’s a huge asset’, he emphasises. The crew really appreciates the simple and logical operating concept and the safety functions The plant activates an alarm when there’s a problem and switches itself off. ‘Then all the operator has to do is just walk over to the machine and diagnose the code. The safety factor that is built into the machines has been instrumental to helping us to learn and understand the machines and keep them running longer,’ says Belleau Another advantage is the use of smart line coupling, which also protects the machines. Sensors detect when the cone crusher gets too full and smart line coupling then automatically reduces the speed of the feeding unit of the upstream jaw crusher.

Reinvestment of revenues
The aim of the Garden River First Nation is the reinvestment of the income from the operations to bolster the revitalisation of the community. Last year, the band built 20 new houses and supplied all the aggregates required from their own plant. And, with the opening of several subdivisions, the economic growth continues. ‘That gives us more work for the community and makes it possible for more people to move back,’ says Belleau. The resurfacing of Highway 17A brings jobs not only in materials processing but also in road construction, where machine operators, construction workers, surveyors and other human resources are required.

Further information:
WIRTGEN GROUP
www.wirtgen-group.com

The Wirtgen 220 SM is breaking new ground in the field of gypsum mining in Brazil

By mining by cutting, a Wirtgen Surface Miner at the Chorado mine in Grajaú in north-eastern Brazil eliminates the need for conventional extraction methods such as drilling and blasting and enables cost-efficient operations with minimal harmful emissions. The deployment of the 220 SM is a technological game changer with a focus on productivity, sustainability, and safety.

The Surface Miner realises a vision for the future

In Brazil, resources have been mined and quarried by drilling and blasting for over 100 years. This was also the standard method used for many years by Gesso Integral at the open-cast mine. However, for CEO Marcos Vasconcelos Ferreira, the not exactly environmentally friendly mining method with its particular need for strict safety precautions no longer represented a forward-looking, state-of-the-art solution: ‘We wanted to achieve high productivity with a tight focus on sustainability.’ During his search for a more sustainable and efficient extraction method, the company CEO came across the Surface Miner from Wirtgen, which cuts, crushes, and, if required, also loads the cut and crushed rock into trucks in a single pass. The raw materials are selectively extracted in purest quality, which allows optimum exploitation of mineral deposits. The potential of the machine and the advantages of the new extraction method were clear: no more drilling, no more blasting, lower emissions, increased safety on the open-cast mining site and outstanding cost-efficiency. The deployment of the first Surface Miner was a technological game changer that more than doubled productivity at the open-cast mine. The purchase of a second 220 SM Surface Miner enabled production at the mine to be increased by 84%.

A personal success story

The success story also has a personal side to it. The company was deliberately looking for an operator with no previous experience with large machines for the new Surface Miner. Marlete Ribeiro Souza Guajajára was recruited locally and trained as a machine operator. ‘My boss told me that he needed an unskilled person he could train from scratch for the job. And that person turned out to be me. At the time, I had never even learned how to ride a bike, a motorcycle or drive a car.’ His trust in the abilities of his new employee paid off. In the meantime, working with the Surface Miner has become second nature to Marlete, and she knows how to make the best of the machine’s advantages. ‘It’s a very comfortable machine that makes our daily work here much easier.’

Efficient mining operations with the 220 SM

Mining by cutting enables the selective extraction of raw materials with outstanding purity. At the same time, it reduces noise and dust emissions and increases safety at the mine. Thanks to low-vibration extraction, the method also enables the exploitation of mineral deposits in the immediate neighbourhood of infrastructure or residential areas. With an average cutting depth of 23 cm and a cutting width of 2.2 m, the Surface Miner enables the company to achieve a production volume of 1.25 million tonnes of gypsum per year. The piece sizes of the cut and crushed material are already ideal for numerous commercial uses and eliminate the need for a classical pre-crushing stage. The Chorado Mine in Grajaú clearly illustrates how increased efficiency and sustainability in the extraction of mineral resources can go hand-in-hand with greater safety in open-cast mining.

Further information:
WIRTGEN GROUP
www.wirtgen-group.com

A MOBIREX MR 110i EVO2 mobile impact crusher and two scalpers from Kleemann process quarried limestone. Their task is the production of material with different specifications to meet local regulations in Alabama and Florida.

A custom solution for two different material specifications

Alabama and Florida have different specifications when it comes to the grain size and composition of the processed material for road construction. The location of the Mohawk Valley Mining quarry in the boundary region of the two states sets the company the task of fulfilling all the specific requirements. The two scalpers –a MOBISCREEN MSS 802i EVO and a MOBISCREEN MS 15 Z – produce the material that meets Florida’s specifications. The oversize grain screened out here is then run through the MOBIREX MR 110i EVO2 impact crusher to produce a final product compliant with the specifications for Alabama.

‘This is a very unusual situation’, says Joey Rutkowski, CEO of Mohawk Valley Mining, ‘which made it all the more important for us that we found Kleemann and the experts who could work with us on solving our problem.’ Through the combination of a MOBIREX MR 110i EVO2 mobile impact crusher with two scalpers, a new MOBISCREEN MSS 802i EVO and its predecessor, a MS 15 Z, purchased as a used machine, Mohawk Valley Mining now has the reliable plant train it needs for processing the challenging limestone material.

Focus on efficiency and user-friendliness

Another important cost factor is the low fuel consumption of the entire plant train. The company was also impressed by the short training and familiarisation period required for its employees, who had no previous experience from working with such machines. ‘The crushing plant’s SPECTIVE operating concept is really intuitive. This saves time and minimizes mistakes’, says Rutkowski. He also sees the simple handling concept reflected in the numerous well-thought-out details, the good accessibility of all components and the automatic mode of the MSS 802i EVO, with which all belt conveyors can be folded in or out in the correct sequence at the push of a button.

Long-term partnership and sustainable success

The mobile solutions from Kleemann make Mohawk Valley Mining’s work much easier and tick all the boxes when it comes to the company’s particular needs. ‘Our collaboration with Kleemann gives us confidence that we will be successful here in the long term’, says Rutkowski. ‘We are definitely on the right track.’

Further information:
WIRTGEN GROUP
www.wirtgen-group.com

The massive plants from Kleemann were transported along the Mazaruni River to two quarries in the deepest interior of Guyana. Here, three PRO plant trains from Kleemann process granite.

In a jungle region that is extremely difficult to reach by water or air, machines have to work particularly efficiently and reliably. Three plant trains were therefore brought step-by-step to the Bartica region in Guyana. The difficult accessibility of the work site and the hard, highly abrasive granite pose particular challenges.

Powerful machines for hard conditions

The three plant trains each consist of a powerful mobile jaw crusher MOBICAT MC 120 PRO, the mobile cone crusher MOBICONE 110 PRO and the classifying screen MOBISCREEN MSC 953 EVO. The plants process the rock into various grain sizes, which are primarily used for the expansion of infrastructure in Guyana.

The granite loaded onto the jaw crusher has a size of 0 to 600 mm. The downstream cone crusher breaks the material into shape and feeds it to the screening plant, which then outputs three classified final products: 0-8 mm, 8-12 mm, 12-19 mm. Larger grain sizes (19-45 mm) are fed back into the cone crusher via the oversize grain returning system. This continuous recirculation ensures that the raw material is fully utilised and that the product quality is very good.

Efficient and intelligent work process for high product quality

One advantage of these plant trains is the intelligent linkage of the machines. Each machine works independently and, in the event of malfunctions or overfilling, sends signals to the upstream and downstream machines. This automatic control enables a trouble-free process. The Continuous Feed System (CFS) ensures that each machine is loaded in a manner that reduces wear and maximises the output. “The automatic control system ensures that all nine machines are evenly utilised. We basically have no unwanted machine downtime”, reports Brian Tiwarie, Managing Director of the BK Group. “Furthermore, the quality of the final product is of decisive importance to us and the Kleemann plants allow use to achieve top quality.”

Experience and reliability impress

The BK Group decided three years ago to acquire the first plant train from Kleemann. Before making the decision, they spoke to other companies about their experiences and also visited the Kleemann plant in Göppingen. In the years that followed, further plant trains were installed with the aim of producing two million tons of aggregates per year.

The company is very satisfied with the product quality and low fuel consumption. ”At this location, where everything really has to be transported by water in a time-consuming manner, high fuel requirements and the transportation of procured spare parts result in additional costs. With regard to these two aspects, we are very satisfied with the Kleemann plants”, says the Managing Director. Kleemann and the regional Wirtgen Group dealer Resansil provide support with reliable service despite the difficult accessibility.

Facts and figures:

Feed material:        Granite
Feed size:              0 to 600 mm
Final products:        0-8 mm, 8-12 mm, 12-19 mm
Output:                  Up to 220 t/hour per plant train,
total: approx. 5000 – 7000 t/day (10 hours a day)

Further information:
WIRTGEN GROUP
www.wirtgen-group.com

Design and range of functions impress with the impact crusher MOBIREX MR 100(i) NEO/NEOe and screening machine MOBISCREEN MSS 502(i) EVO

Kleemann was also honoured this year with the German Design Award for its technically innovative approaches. Two new products from the materials processing specialist received the coveted design award in the “Excellent Product Design” category.

MOBIREX MR 100(i) NEO/NEOe: local emission-free work in the compact class

With the mobile impact crusher MOBIREX MR 100(i) NEO/NEOe, the jury honoured the high flexibility, which the machine owes to its compact dimensions and its low transport weight. Furthermore, with innovative extras, the impact crusher sets new standards in the compact class: Highlights, for example, include the automatic crushing gap adjustment and the tool-free “Lock & Turn Quick Access” system. This allows the crusher to be opened in only 30 seconds without the need for tools. This guarantees efficiency and safety. User-friendliness is also the focus of the SPECTIVE operating concept, which is clearly structured and intuitively designed. The environmentally friendly drive options are future-oriented: The all-electric E-DRIVE drive concept enables locally emission-free work; alternatively, the fuel-saving diesel-direct drive concept D-DRIVE is available.

MOBISCREEN MSS 502(i) EVO with particularly ergonomic operation

The MOBISCREEN MSS 502(i) EVO convinced the jury with its high flexibility and ease of use. Thanks to its compact design and transport-friendly dimensions, the scalping screen is ideal for changing locations. Thanks to the selection of different screen media, it can be individually adapted to specific requirements. Operation of the machine and, in particular, changing of the screen media are ergonomically designed with the user in mind. Sustainability was also a top priority with the MSS 502(i) EVO. The electro-hydraulic dual-power drive operates locally emission-free.

Design Award: Awarded for innovation and function
The German Design Award, presented by the German Design Council, is one of the most prestigious design awards in the world and is highly regarded far beyond specialist circles. Every year, outstanding products that combine pioneering innovations with excellent design are honoured. Both Kleemann machines combine a functional and user-friendly design with a clear focus on safety and sustainability

Further information:
WIRTGEN GROUP
www.wirtgen-group.com

A MOBICAT MC 120 PRO and a MOBISCREEN MSS 802 EVO are deployed for the individualised processing of natural rock

A plant train comprising of a mobile jaw crusher and a scalping screen from Kleemann processes material for the rehabilitation of the infrastructure at an Indonesian lignite mine. 

 The major challenges in the extraction of the material are its scattered locations on the mining site and the frequent need for blasting. In view of this, the ability to easily and flexibly relocate the machines was a crucial factor in the considerations of the mine operator.

 A smooth and seamless process – focused on future needs

The MOBICAT MC 120 PRO is used as a primary crusher, while the downstream MOBISCREEN MSS 802 EVO mobile scalping screen is employed for the screening of the crushed material. Initial results show that the mobile plants from Kleemann enable trouble-free processing of the andesite rock. At the same time, it soon became clear that the machines would have no problems at all with the special demands of processing of this volcanic rock.

Both machines are also equipped with technology that allows operation from an external electric power supply – a future-proof and sustainable option. The infrastructure for this will be realised in the near future. Until then, the operator will continue to benefit from the low fuel consumption of the two machines. ‘The option for operating the machines electrically takes us a big step forward on the way to the achievement of our sustainability goals. Nevertheless, the fuel consumption is very low when we run the machines on diesel’, emphasizes Aditya Maulana Bainal, sales engineer from mine operator PT Bukit Asam Tbk.

Machine options assure efficiency and flexibility

Many of the features of the jaw crusher make a positive contribution to an efficient workflow. The hopper extension, for instance, makes it possible to take on larger quantities of material and increases the hopper capacity from 10 to 13 cubic metres. The hopper walls can be folded out by remote control from the ground. The feed material is screened effectively by the independently vibrating double-deck prescreen. This enables fines to be removed via the side discharge conveyor before they reach the crushing chamber. The conveyor unit is also hydraulically foldable, and can remain on the machine during transportation. The rock chisel, a further equipment option for the jaw crusher, can break up larger boulders in the feed material at the machine before it is passed to the crusher. This enables easy removal of blockages caused by material bridging during the passage of material from the prescreen to the crusher. Another advantage is that the rock chisel can remain on the machine during transportation.

Satisfied with service and handling

Aside from the performance and equipment options, which ensure an efficient and effective production process, a further decisive factor is the outstanding on-site service. A service technician from Kleemann spent two weeks at the site setting up the machines and training the local personnel in readiness for the start of production. This also included a series of theoretical training sessions, practical application training and trials.

Further information:
WIRTGEN GROUP
www.wirtgen-group.com

Advantages and infrastructure requirements

Mobile crushing and screening plantsthat are operated with electricity instead of diesel fuel are regarded as particularly environmentally friendly because they do not emit CO₂ on site. They are also ahead in terms of cost-effectiveness in the long term. Sustainable, low-emission solutions are in demand, and companies can position themselves on the market as future-oriented providers with electrically operated mobile plants. Although the initial investment costs are higher, they are quickly amortised due to the fuel savings. A sample calculation for the German market shows that this is already possible after around six years – if the system can be supplied with energy via the customer’s own photovoltaic system, even after around four years.

Prerequisites for electric operation

“Our mobile plant train in the sample calculation consists of a jaw crusher MOBICAT MC 120 PRO, cone crusher MOBICONE MCO 110 PRO as a secondary crusher and a downstream screen machine MOBISCREEN MSC 953 EVO. The plant train consumes an average of approx. 77 litres of diesel per operating hour. In the electrified version, it has an average current consumption of 302 kW per operating hour. The maximum power requirement is 542 kilowatt“, says Tobias Böckle, head of Product Management at Kleemann. “The energy requirement must first be provided by the infrastructure and is ideally met by electricity from renewable sources. A sustainable and quickly cost-efficient solution is to use an in-house photovoltaic power supply,” says the expert.

A suitable design of the infrastructure in advance is of decisive important for efficient use. Tobias Möß from Wolff & Müller GmbH explains: “First of all, the actual energy requirements of the plant and the demand of all already existing consumers should be determined. How much power is needed on the entire company premises? The load profile must also be taken into account. When are the power peaks, when are the times with lower consumption? The individual load profile can be obtained from the energy supplier or network operator.

Many companies already have a transformer on their premises that adapts the voltage to requirements and, for example, provides low voltage for systems. Once the required power has been calculated, it is necessary to check whether the available transformer is sufficiently dimensioned. Does it deliver the required power? The amount of power that can be drawn from the transformer is indicated on the type plate.

It is also important to consider where the main distribution is located on the site and where the system will be used. Good planning here is a precondition for efficient operation. Example: The electrical energy required to supply the plant is not transformed to low voltage directly at the transfer station, but is instead routed over the medium-voltage level across the site to the plant – the cable cross-section can therefore be much thinner, making the cable easier to handle and significantly cheaper.

At the mobile plant, a second transformer converts the current into low voltage in order to operate the mobile crushing or screening plant. The aim here is to develop a suitable individual concept.

Rapid amortisation of the investment costs

With a solid foundation, the investment costs are amortised after around six years – or even sooner, depending on the energy concept. From this point on, all-electric operation will save considerable operating costs year after year.

Here is an overview of the switch to electricity as an example: With the diesel-powered plant, there is no need for additional investment in the infrastructure apart from the fuel costs. The cost of diesel fuel varies greatly depending on the country and region, so any savings depend on the difference in price between diesel and electricity.

Electrically operated crushing and screening plants are initially more expensive due to their special equipment, plus the cost of cables (depending on the length of cable required) and a transformer.

All-electric operation incurs initial investment costs, but these pay off for the operating company in the medium term. On closer inspection, the one-time costs quickly turn into a worthwhile investment. In many cases, climate protection regulations lead to stricter requirements. The electric drive is a decisive competitive advantage, for example when local authorities demand emission-free operation in city centres. “Especially in combination with your own PV system, electrical operation becomes a climate-friendly, cost-efficient concept in just a few years, which not only provides the operating company with financial benefits, but also reflects the company’s efforts to achieve greater sustainability,” Tobias Böckle is convinced.

Environmentally friendly operation is also possible at locations where electricity cannot be supplied due to a lack of infrastructure. The electric version of Kleemann plants can also be operated autonomously with sustainable HVO diesel.

Further information:
WIRTGEN GROUP
www.wirtgen-group.com

A New Cutting Drum Expands the Range of Applications for Surface Miners in Hard Rock and Stone

Wirtgen Surface Miners and Cross Application Miners are deployed around the world in open-cast mining operations and on infrastructure projects. Cutting drums are the core element of the machines. At MINExpo 2024, from September 24 to 26, 2024 in the Las Vegas Convention Center, the highlights from the Wirtgen Group will include insights into its cutting technology solutions. The focal point on Booth 6815 at the show will be a new cutting drum that now also enables the cost-efficient extraction of resources with uniaxial compressive strengths of over 100 MPa UCS (14,500 psi).

Limestone, Gypsum, Anhydrite, and Other Hard Rocks and Minerals

The new cutting drum is equipped with HT14 toolholders and features a redesigned cutting geometry. The field-proven and established central-drum concept, which ensures optimum utilization of the machine weight, and the direct belt drive that guarantees the transfer of high usable power to the cutting drum, also contribute to the ability of Surface Miners to profitably extract even very hard rocks and minerals with uniaxial compressive strengths of 100 MPa UCS (14,500 psi) and more – for instance limestone, gypsum, or anhydrite.

The Wirtgen 280 SM(i) with the New Cutting Drum in Action

The new cutting drum celebrated its premiere in practice on a limestone quarrying job carried out by a Surface Miner 280 SM(i) in Louisville, Nebraska. In addition to the extraction of very hard limestone at the quarry, the elimination of the need for drilling and blasting made it possible to extract previously unexploitable limestone deposits and extend the working life of the quarry and all downstream production systems by several decades. For the quarry operator, surface mining is a cost-effective extraction solution that also contributes to safeguarding jobs, increases safety in the quarry, and enables responsible management of resources.

Faster Infrastructure Projects

Wirtgen expanded its portfolio of products and applications with the Cross-Application Miner 260 SX(i) two years ago. The Cross Application Miner speeds up construction times by eliminating the need for drilling and blasting, with the construction of stable embankments, in-situ grading of railroad tracks, and the recycling of the extracted material in-place for use in further construction.

Wirtgen Group Services: Expertise and Best Practices Are Essential

At MINExpo 2024, trade and industry visitors to the show will also be able to talk with surface mining experts from the Wirtgen Group about all other aspects of the solution – for example deployment and project assessment, recommended machines and equipment, related cost and performance estimation, and financing solutions.

Further information:
WIRTGEN GROUP
www.wirtgen-group.com

In a quarry in Louisville, Nebraska/USA, a Wirtgen Surface Miner 280 SM(i) is being used for the layer-by-layer and particularly environmentally friendly extraction of limestone from previously undeveloped reserves. Limestone for the production of cement has been quarried here in Louisville since 1929.

The extraction of the material in the quarry was contracted out to North American Mining (NAM). The limestone reserves in the quarry in Louisville are by no means exhausted, even though it has now been in operation for almost 100 years. The geological situation, however, has made extraction a more difficult task, as the remaining limestone strata are interlayered with shale. Due to this, quarrying with conventional methods such as drilling and blasting would have led to contamination of the material. The Ash Grove Cement Company therefore decided to use a Wirtgen Surface Miner from NAM for the job. As the 280 SM(i) enables selective extraction of the primary resource, it can guarantee outstanding material purity and is the ideal choice for projects in areas with sensitive infrastructures.

The 280 SM(i) cuts, crushes and loads the extracted material in one single pass. This means that processes such as pre-crushing, or conventional extraction processes such as drilling and blasting, are no longer necessary. This not only enables enormous savings in terms of costs, but also the extraction of materials in areas that are otherwise hard to access or prohibit the use of drilling and blasting due to the difficulty of obtaining appropriate permits.

The use of Surface Miners opens up entirely new opportunities for the extraction of limestone in the quarry at Louisville. The extraction of the material takes place in a selective, layer-by-layer process. The valuable limestone resource is cleanly separated from waste materials such as shale before crushing with extremely high output and efficiency. Considering a compressive strength of 110 MPa for the limestone here, the 280 SMi achieves a mean cutting rate of approximately 400 t/h (Figure 1) – with 87.5 % of the material produced in the process being crushed into pieces smaller than the specified maximum size of 7.6 cm. In the waste rock (shale and overburden), the machine achieves a mean cutting rate of approximately 650 t/h. The cut and crushed material is loaded directly into 70 t dump trucks driving alongside the Surface Miner (Figure 2). The process is fast and continuous, with a fresh truck being filled with crushed limestone every 4 min – around the clock, five to six days a week.

Due to the high compressive strength (extreme hardness) of limestone, the cutting tools used here are subjected to enormous stresses. The 280 SM(i) in use in Louisville is ideally prepared to take on this challenge and achieves maximum cutting rates with minimal pick wear. “The machine does a great job. I’m really impressed with the round-shank picks and the quick-change toolholder. They make it so easy to change worn picks that we can get back to work again after stopping for only a couple of minutes”, says David Ashby, machine operator from NAM, who has more to say about the machine: “One of the advantages of the movable counterweight and the 90° slewing angle of the discharge conveyor is that they let you work very close to the high quarry walls. Although the machine is very big, its simply fantastic manoeuvrability makes it very useful for working in tighter spots.”

Apart from its efficiency, the machine also impresses with a range of environmentally friendly aspects: The number of extraction processes is reduced from four to one, while lower exhaust, noise and dust emissions not only make every day work on the site much easier, but also offer new opportunities for quarrying rock close to populated areas. “We can now extract limestone from deposits we could hardly have reached before”, explains Nic Haubruge, Business Development Manager at NAM. “In many cases, the use of drilling and blasting is simply no longer a viable option, however, with this machine we can develop new deposits with minimal dust emissions, minimal noise emissions, and no vibrations.”

Further information:
WIRTGEN GROUP
www.wirtgen-group.com