BAUER AG

Carbon is one of the most important building blocks of life. It serves as the basis of all natural materials and forms numerous bonds. When forests die, e. g., CO₂ enters the atmosphere and is bound by plants or rivers somewhere else. As a result, carbon is simply everywhere. And there’s now more of it in the air than the natural cycle is able to neutralize. Carbo-FORCE GmbH has a strategy to counteract this: This startup from the northern German town of Preetz has developed groundbreaking plant for the carbonization of biomass. On 1st January 2023, BAUER Resources GmbH, Schrobenhausen/Germany, acquired 50 % of the company’s shares (Figure 1).

But how does this innovative plant work? The technology is based on the traditional principle of carbonization. This is none other than pyrolysis, in which the biomass, from (scrap) wood and horse manure all the way to fermentation residues or sewage sludge, is heated to very high temperatures in the absence of oxygen. As a result, a large share of the carbon is bound and not entirely emitted into the atmosphere as it would be with incineration. The end product is biochar, which has a variety of possible uses: in agriculture for soil improvement, in livestock farming as feed charcoal, as an insulating material or as activated carbon filter. “Depending on the initial material, 1 t of biochar can bind more than 3 t of CO₂,” explains Kai Alberding, Managing Director and founder of Carbo-FORCE. In this way, the equipment actively produces carbon credits as well as exhaust heat. Hardly any energy is required during operation, just at the start of the combustion process. “Far more energy is generated than consumed – the plant is almost self-sufficient,” summarizes Alberding. Due to their modular design in the form of containers, these durable plant can be individually adapted and positioned in a decentralized manner.

“For a long time now, Bauer Resources has stood for simple technologies combined with decentralized solutions. This is why the groundbreaking carbonization plants from Carbo-FORCE are an ideal addition to our portfolio,” underscores Roman Breuer, Managing Director of BAUER Resources, and adds: “At the same time, we are reinforcing the expansion of our energy division with this step.” For Carbo-FORCE, the collaboration offers considerable added value in other respects: “In Bauer Resources we have found a long-term partner who provides us with the necessary production capacity and a suitable sales network,” says Alber­ding. The equipment will be constructed by a subsidiary of Bauer Resources – SCHACHTBAU NORDHAUSEN GmbH – a specialist in plant engineering with more than 30 years of experience in the field.

As a result, both companies will benefit from the future collaboration as they join forces to address important topics: the reduction of CO₂ emissions and the generation of sustainable energy. (BAUER/Si.)

After three years, it was finally time again on October 24: Bauma – the world’s leading trade fair for construction equipment, construction material equipment, mining equipment, construction vehicles and construction machines – opened its doors at Munich’s exhibition grounds. In a hall area of roughly 200,000 m² and an outdoor area of more than 400,000 m², more than 3,000 exhibitors from 58 countries presented exhibits until October 30. Among them, of course, was once again the BAUER Maschinen Group, which welcomed numerous guests at the entirely redesigned and certified climate-neutral exhibition stand with an urban character. Apart from Bauer drilling rigs, duty-cycle cranes from the MC series and diaphragm wall equipment, Bauer also displayed equipment and machines from the subsidiaries KLEMM, RTG and Bauer MAT – including some world firsts.

“For more than half a century, our high-performance and highly efficient equipment has been setting standards in specialist foundation engineering,” says Dr. Rüdiger Kaub, Managing Director of BAUER Maschinen GmbH. “We are proud of this, but we don’t rest on our laurels: we are making great strides on the path to a sustainable future with our numerous innovations that we presented at Bauma. We look forward to taking this journey together with our customers and partners.”

Michael Stomberg, CEO of BAUER AG, adds: “The topics of urbanization, energy supply and climate change pose a variety of challenges for us. With our machines, equipment and digital solutions, we contribute to mastering these challenges and building the foundation for the world of tomorrow.”

Alternative drives for increased flexibility on construction sites
This year’s Bauma was entirely focused on digitalization and sustainability – two keywords that also play a central role at Bauer. In mid-2021, Bauer brought its first drilling rig with an electric drive on the market, the eBG 33. Now the company has opened up another chapter in electrification at Bauma and presented the new, fully battery-powered version of its electrical drilling rigs: the fully electric BAUER eBG 33 H all electric. With the additional electrification of the main consumers such as the rotary drive and main winch, it defines new standards for energy efficiency. Locally CO₂-free operation with highly efficient energy use and low noise emission values are benefits for operators, residents and ultimately the environment as a whole. This new eBG model relies on a completely new generation of the B-Tronic control and visualization system, the B-Tronic 5, with innovative solutions in human-machine interaction and additional functions in the area of data management.

First hybrid model in the telescopic leader segment
RTG Rammtechnik GmbH also unveiled a true world first: the RG 19 T hybrid. The system capacity is achieved with a diesel engine and an additional electric drive, which considerably reduces the CO₂ and noise emissions. With this model, RTG is setting standards in the telescopic leader segment. All RG models on the BS 55 RS and BS 65 RS base carriers can be offered with this hybrid technology in the future. Of course, the “operate” remote control is also available in the hybrid version. The new RTG Pile Driver app allows the operator to handle the machine quickly and safely. In addition, complete service can be carried out on the equipment with the help of the app.

KLEMM Bohrtechnik GmbH also presented an electric model, among other equipment: the exhibited KR 806-3E features proven technology from the KR 806-3GS rig, however as an electrohydraulic, emission-free variant. The intelligent control system enables the use of batteries as a booster for drilling operation to reduce the required electricity load. Compared to the diesel-hydraulic variant, there are no restrictions when it comes to power and application. .

The electric equipment portfolio of the BAUER Maschinen Group is rounded off by the electrically powered duty-cycle crane from the MC series, which already attracted attention at Bauma 2019, as well as the innovative BAUER Cube System. Bauer brought the system on the market in 2021 and now presented it at this year’s Bauma to a wider audience of international professionals. Since its market launch, the system has gone through a number of tests. In order to demonstrate this at the trade fair, a complete overhaul of the equipment was deliberately avoided. What makes this world first unique: the cutter system, including hose drum system, fits into three conventional 20-foot high cube containers. As a result, it can be easily used in 3 x 3 m diameter tunnels, which is a major advantage for trench cutter projects in densely populated large cities. Whether for above-ground or underground use, large-scale closures of urban areas could potentially be a thing of the past, since the impact of construction sites on traffic, businesses, and residents (in particular) are minimized. Last but not least, the electric drive considerably reduces the ecological disturbance of a trench cutter jobsite.

“With our extensive product range, which includes specialist foundation engineering equipment with classic diesel, hybrid and electric drives, we allow our customers to have the highest possible flexibility for their construction site,” says Dr. Rüdiger Kaub.

Sustainability – also a question of efficiency
When it comes to sustainability, in addition to the type of drive in the equipment, another factor plays a decisive role: how efficiently the equipment operates on site. A decade ago already, Bauer Maschinen laid the foundation for today’s modern diesel-operated drilling rigs. The TEAM project, which addressed the development of technologies for energy-saving drives in mobile working equipment, resulted in the creation of the EEP Energy-Efficient Power package. It includes numerous modifications to improve efficiency. The drive system of the main winch, which represents a significant share of energy consumption especially in Kelly drilling, was thoroughly reworked. The system makes it possible to recapture energy released during the lowering process. Particularly with deep drilling operations, this allows for significant reductions in fuel consumption. Other advantages include needs-based output control of the fan speed. This not only affects efficiency, but also the drilling rig’s considerably lower noise emissions compared with earlier generations. The same applies for optimized engine control: depending on the activated consumer function, the speed of the diesel engine is controlled intelligently to the lowest possible value using the eco mode. A large-scale hydraulic system reduces output losses to a minimum. Consequently, in addition to the fuel savings, more power is generated at the consumer. Reduced losses, i.e. improved efficiency, also means more power where it is needed: at the rotary drive and at the main winch.

All these are installed as standard features in today’s diesel-operated Bauer drilling rigs and contribute to sustainability, efficiency improvement and reduction of operating costs. Depending on the equipment size, up to 30% in fuel can be saved – with productivity increases of up to 10% and considerably reduced noise emissions by up to 50%.

Sustainable methods reduce the carbon footprint
In addition, the choice of method has a significant impact on the CO₂ footprint of a site. Soil mixing techniques that are sustainable because they conserve resources, like the cutter soil mixing (CSM) method patented by BAUER Maschinen GmbH or the single column mixing (SCM) method, offer a major advantage: the existing soil is loosened and mixed with a self-hardening slurry. This significantly reduces the number of transports that are needed (e.g., to bring concrete to the site, or excavated soil from the site to the landfill). Demand for such methods is increasing globally, and here Bauer not only delivers the equipment but also the right tools.

At Bauma, two exhibits with equipment for soil mixing were presented: a BG 45 with a single column mixing double head mixing drive (SCM-DH) that can be used to construct columns with a diameter of up to 2,400 mm through the reverse rotation of the mixing tools, and also an RG 21 with the new BCM 5L cutting and mixing unit to execute the CSM method.

Innovation Award and EuroTest Prize
BAUER Maschinen GmbH was delighted to receive two prestigious awards during Bauma. On the eve of the opening of the trade fair, the Innovation Awards were presented. In the Research category, the Deep Sea Sampling joint project took first place. Martin Sobczyk from the TU Bergakademie Freiberg accepted the award on behalf of the project participants. About the project: Whether copper, cobalt or rare earths, the global demand for these and other raw materials is already enormous. And it will continue to increase in the coming years. To meet the demand for raw materials in the long term, existing capacities must be expanded and new deposits sustainably developed. The issue of deep-sea mining is therefore more topical than ever. It requires a consideration of the potentials and impacts across all disciplines. The Deep Sea Sampling research project is making an important contribution to this. Project partners are the TU Bergakademie Freiberg with its Institute for Processing Machines and Recycling Systems Technology and the Institute for Mechanical Engineering, the University of Rostock, the FAU Erlangen-Nuremberg as well as Krebs & Aulich GmbH and BAUER Maschinen GmbH. The German Federal Institute for Geosciences and Natural Resources (BGR) as well as the Deep Sea Mining Alliance (DSMA) are also represented in the committee accompanying the project.

Just a few days later, Bauer received the EuroTest Prize 2022 from the German Employers’ Liability Insurance Association for the Construction Industry (BG BAU) for its innovative Stability Plus assistance system. It aims to further increase the safety and user-friendliness of the drilling rig while significantly improving its performance. Stability Plus optimizes the horizontal extension of the drill mast, the positions of the main consumers and the slewing speed of the upper carriage. The operating forces according to the stability tables in the respective rig state are displayed to the operator in real time on the B-Tronic user interface. This significantly reduces the operator’s workload, eliminating the need to look up and memorize the complex data tables. In addition, the operator can independently select data records already stored in the B-Tronic control system for various equipment configurations and flexibly load them into the machine control system. This eliminates the need for service technicians. If new equipment data sets are required, they can be ordered from Bauer Maschinen and imported into the machine control system via the Internet using Data2Rig functionality via the DTR module.

“The inventive spirit in the many large and small companies is paving the way for Vision Zero in the construction industry. After all, their ideas for occupational safety and health help prevent accidents and work-related illnesses and make construction sites safer,” said Prof. Frank Werner, Deputy Head of BG BAU’s prevention department, at the awards ceremony. “With innovative work equipment and approaches to solutions that ensure greater safety on construction sites and in the skilled trades, this year’s winners of the EuroTest Prize impressed the expert jury.”

Apart from all these innovations and world firsts, Bauer did not neglect cherished traditions this year, such as inviting customers and partners to a Bavarian evening at the headquarters in Schrobenhausen, Germany. “Our guests particularly appreciate our friendly, down-to-earth atmosphere. We have known many of them for decades,” says Dr. Rüdiger Kaub. “It is important for you and for us that you feel that when you purchase Bauer equipment, you’re not just a customer. You become part of our global Bauer family.”

Further information:
BAUER AG
www.bauer.de

A long-established tradition: For more than 30 years, BAUER Spezialtiefbau GmbH has been hosting the “Schrobenhausener Tage” event. This traditional event was held in early June this year under the slogan “B.sustainable: Sustainability in specialist foundation engineering.” What made this event unique: After a three-year break, it was finally possible to welcome the guests personally again in Schrobenhausen.

In the morning, guests were given an introductory talk from Arnulf Christa, CEO of BAUER Spezialtiefbau GmbH, in the Old Welding Shop: “Sustainability requires taking on responsibility. Accordingly, the development of resource-efficient, environmentally compatible innovations and technologies has for years now been a clear focus at BAUER Spezialtiefbau GmbH. We are proud to make an important contribution with our ideas.” The goal is to reduce the impact of specialist foundation engineering on humans and the environment, use raw materials more efficiently and manage projects in a sustainable and environmentally friendly manner. Looking back on the past two years, he reported in continuation: “Because of the pandemic, we had to deal with many challenges that required us to react flexibly. Nevertheless, our site teams around the world were fully committed – where possible – to successfully executing projects.”

In the exhibition area, participants were then able to visit various stations of the departments Technical Services, Design and Digitalization. The latest developments from Bauer were presented here – an excellent opportunity for guests to engage in dialogue with the experts. Last but not least, BAUER Maschinen GmbH also presented its innovative BAUER Cube System as well as its first electrified drilling rig.

The main series of lectures was then held in the afternoon as a hybrid event, with national guests participating on site and international guests participating via webinar. Hans- Joachim Bliss, former Managing Director of BAUER Spezialtiefbau GmbH, led the guests through the program with exciting and varied project presentations, live transmissions from sites in Germany and abroad as well as interactive discussions. For the international guests who participated virtually, the presentations were translated simultaneously.

Florian Bauer, Member of the Executive Board of BAUER AG and Managing Director of BAUER Spezialtiefbau GmbH, opened the series of presentations. He emphasized how important the topic of digitalization has become for specialist foundation engineering in his presentation “Digitalization at Bauer – Solutions for today‘s Construction Sites”. “The digital site is versatile. Apart from the use of digital tools such as data management software, databases or artificial intelligence, it is people, our employees, our teams, who are responsible for the success of our sites. Without them nothing would be possible,” he remarked.

This was followed by the first live transmission, from the Cairo Metro site in Egypt. Mohamed Sherif, Project Manager at Bauer Egypt, reported on the project, where top- down construction is currently being executed for the rapid transit system. Next came another live report from a site in Munich, Germany, given by Jee-Sun Rössler and Stefan Jäger, Sales Engineers for the south region of Bauer Spezialtiefbau. “For this project, the mixed-in-place method is being used. This involves using the existing soil as an aggregate. Removing the material becomes unnecessary, which can save time and money, but first and foremost CO₂.

After the live transmissions with Cairo and Munich there was a talk by Dr. Karsten Beckhaus, Head of the Technical Service Department at BAUER Spezialtiefbau GmbH, dedicated entirely to the topic of “B.sustainable: Sustainability in specialist foundation engineering.” He explained: “Our top sustainability goal is to be climate-neutral by 2050.” He further emphasized: “In this context, we are focusing on providing sustainable products for our customers.”

This year’s series of presentations concluded with a live transmission from Alaska: Bruno Luz, Project Manager at the US subsidiary BAUER Foundation Corp., reported on the extreme working conditions and logistical challenges involved with reinforcing the Moose Creek dam in the northern Arctic Circle. Between the presentations, the guests had the opportunity to ask questions through an online voting portal and engage directly in dialogue with the presenters.

The event was a resounding success, with approximately 150 participants on site and around 300 online viewers. This year, the traditional event concluded with lively discussions during a relaxed dinner.

Further information:
BAUER AG
www.bauer.de

Sankhuwasabha District, Nepal – The Arun River in Nepal flows from Tibet through the Himalayas into China. Of all Nepalese river basins, it has the largest area covered in snow and ice. A new hydroelectric power plant is currently being constructed on this river, and it is expected to produce up to 900 MW of electricity.

BAUER Engineering India Pvt. Ltd., a subsidiary of BAUER Spezialtiefbau GmbH, was tasked by the Indian company Jaiprakash Associates Limited with the construction of a cut-off wall as part of the project Arun III HEP. The goal is to achieve a seal and reduce seepage water below the upstream cofferdam and in the left and right abutments.

The scope of service provided by Bauer includes the execution of 3,500 running meters of drilling and injection work on the cofferdam. In the granular construction soil, composed of sand, gravel, rubble and boulders, the pore injections are executed by means of tube-à-manchette and annular grouting.

“Using the pore injections, we are able to fill the pores in the very loose soil with cement slurry and thereby reduce its permeability”, explains Project Manager Satish Kumar. He continues: “Injections require a high degree of quality assurance and quality control. We are able to meet the strict demands thanks to our many years of experience.” In addition to the pore injections, Bauer will also carry out rock grouting in order to fill gaps, fractures and cavities in the rock.

Due to the remote location in the Himalayas, not only the construction soil poses a challenge, but also logistics. On top of that, the schedule is very tight: this is because snow starts to melt in March, causing the water level in the river to rise and making work more difficult.

A KLEMM KR 909 is being used for the drilling and injection work. The work executed by Bauer started in December 2021 and is expected to be completed by May 2022.

Further information:
BAUER AG
www.bauer.de

Since the mid-1980s, hardly any other method has changed specialist foundation engineering as markedly as the development of diaphragm wall equipment. One milestone in this process was the introduction of the first Bauer trench cutter, which was used in 1984/85 to seal the Brombach Reservoir in Franconia (Figure 1). In just four months, this innovation conceived by Bauer engineers was designed, constructed and brought to the site – with resounding success: Despite some initial difficulties, the prototype was used to construct a wall 60 cm thick and 40 m deep. “This ‘technical adventure’ marked the start of a true success story, which has repeatedly gone beyond the limits of what was previously feasible and that is far from over,” says Leonhard Weixler, head of the Diaphragm Wall Equipment division at BAUER Maschinen GmbH. Since 1985, he has overseen the development of Bauer cutter technology in various roles.

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Special applications for Bauer cutters

In the following years, cutter technology at Bauer advanced in great strides – “always highly pragmatic, but also at times very bold and creative,” recalls Leonhard Weixler. The first cutters were sold to Japan and Turkey. In collaboration with a French partner, the maneuverable City-Cutter BC 15 was created for work in tight spaces and with working heights of just 5 m. New applications were later opened up with the Low Headroom machine that Bauer introduced on the market at the end of the 1990s. This was used to execute the encompassment of a subway station in Singapore underneath an existing airport building. Another machine of this type was used in China a few years later, in the Yeleh Dam project, to construct the sealing wall for a reservoir dam in a narrow tunnel.

Then in 2014, the CBC 40 Silent Cutter ushered in a new generation of equipment for projects in urban environments. The equipment performed impressively when it was used for a subway project in Singapore, particularly due to its low noise emissions, but also thanks to its compact dimensions, which were possible because of measures such as attaching the hydraulic power pack on the side. Next in summer 2019, an impressive depth record was set by a BAUER BC 50 cutter on an MC 128 duty-cycle crane: During a mining project in Canada, cutter excavation was for the first time carried out up to a depth of 251.4 m (Figure 2).

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Standard equipment in specialist foundation engineering

“In addition to all these special applications – some of them in difficult geological conditions – our cutters have also become established as reliable standard equipment in specialist foundation engineering, for example in the construction of diaphragm walls that can serve as retaining structures, for cut-off wall construction or as a foundation element,” emphasizes Leonhard Weixler. In addition, cutters also play an important role in soil mixing techniques such as Cutter Soil Mixing (CSM): Cutting wheels loosen the soil and mix it with a slurry to form a homogeneous soil-bentonite mortar. The method can be used to construct cut-off walls and retaining structures in various soil types, including hard soils.

Over the decades, Bauer has built and sold hundreds of cutter and CSM units. “The reliability of our equipment is largely also based on our decades of experience,” says Leonhard Weixler. “And our customers can also depend on that.” In recent years, however, the orientation for new developments and enhancements in Bauer cutter technology has been provided not only by customer requirements, but also by two major trends. “The topics of urbanization and sustainability are becoming increasingly important. They require proactive solutions, such as our first electrically powered cutter unit based on a BAUER MC 96 duty-cycle crane, which we presented in 2019 at the Bauma in Munich,” continues Leonhard Weixler.

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New applications

Finally, Bauer presented an innovation last year that opens up entirely new applications for the future of diaphragm wall construction: the electrically powered BAUER Cube System (Figure 3). This was developed precisely in the dimensions of a container. As a result, it can be easily used in tunnels with a diameter of just 3 x 3 m, a major advantage for cutter projects in densely populated large cities, for example. “The BAUER Cube System can be used precisely where the diaphragm wall needs to be constructed: underground,” summarizes Leonhard Weixler. This means that large-scale closures of urban areas could potentially be a thing of the past. The impact of construction sites on traffic, businesses, and residents (in particular) are minimized, even during daytime use. Another advantage is that the electric drive system considerably reduces the ecological disturbance of a cutter site. When it comes to logistics, the system’s compact dimensions are another major advantage. Instead of expensive heavy haulage, individual elements of the system can be easily transported to their place of deployment as conventional containers. “All in all, the BAUER Cube System sets new standards when it comes to sustainability in cutter technology,” concludes Leonhard Weixler.

Further information:
BAUER AG
www.bauer.de

BAUER Technologies Ltd, the UK subsidiary of BAUER Spezialtiefbau GmbH, Schrobenhausen/Germany, is now a leader in the field of sustainable resourcing and has been accredited with the sustainability certificate BES 6001.

BES 6001 is a certification method developed by Building Research Establishment (BRE) England. This “Framework Standard for Responsible Sourcing” outlines a framework for company leadership, supply chain management, as well as ecological and social aspects. These factors must be addressed to ensure sustainable procurement for construction products. In October 2020, BAUER Technologies Ltd began the application process for the BRE BES 6001 standard for the sustainable construction of pile foundations – and their efforts have now paid off: BAUER Technologies obtained the certificate in November 2021.

Bauer Technologies specializes in the design and execution of complex foundation projects in Great Britain and Ireland. The company has been procuring materials responsibly for many years. Nevertheless, demonstrating the company’s commitment to sustainability has been difficult and time-consuming until now, both for Bauer Technologies and for clients who require an easier option for evaluating this type of certificate. Obtaining the BES 6001 certification for responsible procurement now provides security for the clients of Bauer Technologies. Certification by a third party clearly shows the company’s commitment to managing the long-term environmental footprint of the sector.

Commenting on the accreditation, Michael Jones (Figure 1), Managing Director of BAUER Technologies Ltd, said: “We are proud to obtain this certification. The fact that we are the only specialist foundation engineering company in the UK with this certification fills us with pride. Sustainability in our supply chain, our processes, our construction and business activities, as well as all areas of the construction sector is absolutely essential for us. Last but not least, this certification is also of major importance for our clients.”

By checking for the BES 6001 certification of Bauer Technologies in the Green Book Live Service provided by BRE Global, clients can quickly and easily review the company’s sustainability certificates and obtain additional BREEAM points for their projects thanks to this certification. BREEAM stands for Building Research Establishment Environmental Assessment Method and is the oldest and most widely used certification system for sustainable construction.

Further information:
BAUER AG
www.bauer.de

Seafloor massive sulfides are a valuable mineral raw material found at the bottom of the deep sea. The “Vertical Approach” is a method for extracting seafloor massive sulfides using the trench cutter method, an established technique in specialist foundation engineering that is operated and supported in the deep-sea environment from a ship on the open sea. As a relatively small-scale intervention with a minimal ecological footprint, this approach is an ideal method for test mining and exploration of deposits up to a depth of 3,000 m.

The approach was conceived in discussions between BAUER Maschinen GmbH, Schrobenhausen/Germany, and the Harren & Partner Group, Bremen/Germany, concerning opportunities to combine the expertise of both companies and to develop new strategies for sustainable mining approaches in accordance with the standards of the International Seabed Authority (ISA).

On 26th August 2021, a joint venture agreement was signed between the two companies and Seabed Mineral Services GmbH was established (Figure 1). The first stage is to determine the economic viability and, in particular, the environmental compatibility of the “Vertical Approach.”

“We are thrilled to have found an expert partner in BAUER who is willing – just like us – to seize opportunities and take on a pioneering role in the field of deep-sea mining. Our joint approach for this venture is based on a combination of established technologies. This enables us to minimize the technological risk while at the same time keeping costs down,” says Heiko Felderhoff, Managing Director of Harren & Partner.

Leonhard Weixler, head of the Diaphragm Wall Equipment division at BAUER, adds: “The chemistry between us is very good; we share a similar spirit. This partnership is an ideal union of specialist knowledge and experience in the field of offshore technologies and services with expertise in the development and production of specialist foundation engineering equipment for onshore and offshore customers around the world.”

Felderhoff and Weixler act as Managing Directors of Seabed Mineral Services GmbH.

Deep-sea sampling undeniably has an impact on sensitive deep-sea ecosystems. Nevertheless, the “Vertical Approach” makes the utmost effort to minimize the ecological footprint. A serious concern when it comes to deep-sea mining is the stirring up of sediment and the potential impact on sensitive deep-sea species. To prevent fine material from escaping the cutting area, a protective collar is positioned around the cutting wheels at the start and the actual cutting process is protected by the surrounding ore. As a result, fine material from the cutting process remains within this area, while the water mixed with fine sediment and cutting chips is pumped into the ore container.

The separation process is carried out within the ore container to separate the particles from the sea water via sedimentation. After this treatment, the water is fed back to the cutting wheels and reused in the cutting circuit. This closed system minimizes the volume of sea water that is impacted by the cutting process.

Sampling is selective. The template and trench cutter are lowered using a cable winch instead of being initially positioned then moved horizontally along the seafloor (Figure 2). This restricts the sphere of influence to the base area of the template feet and trench cutter. Zones with ore can be clearly separated from zones without ore.

Another aspect of the “Vertical Approach” that reduces the environmental impact of this method compared to other methods is that only one “tool” is used for extracting material. The soil does not need to be crushed later for transport to the ship. Only the raw material is extracted, with minimal impact on the environment.

Weitere Informationen:
BAUER AG
www.bauer.de

Schrobenhausen, Germany – What started as an idea is now reality: At this year’s in-house exhibition with the slogan “BAU ERLEBEN,” BAUER Maschinen GmbH is presenting the new eBG – the first electric drilling rig manufactured by Bauer (Figure 1). The equipment relies on electrical power instead of a diesel engine, so it does not require any fossil fuels, and operates extremely quietly, making it perfect for use in cities. “We have been working with electrification for some time now,” explains Christian Heinecker, Head of the Drilling Equipment division at BAUER Maschinen GmbH. “In the past, however, this was tailored to specific customer requests or projects.”

At its heart, development of the new eBG is a component of “Zero Emission”. This encompasses various spheres of activity such as sustainability, recycling, energy, CO₂ footprint and noise emissions. The electrical operation of drilling rigs is therefore simply the logical next step towards climate neutrality.

Previously, electrification of Bauer equipment has only been applied in specific cases such as the Dive Drill, a drilling rig operated from ships for underwater drilling in which electrically driven hydraulic power packs were installed, or in the area of deep drilling technology with the electrically driven Top Drive. “Electrification has entered our standard portfolio in the form of individual products as well as deep drilling technology,” says Christian Heinecker. The first duty-cycle crane with an electric motor was presented at Bauma 2019 in Munich: the BAUER MC 96, with a trench cutter that is suitable for urban construction as well as for the construction of subway shafts.

The new eBG 33 (Figure 2) falls in the mid-range segment of the drilling rig series with a drive power of more than 400 kW, which puts it on the same scale as a BG 28 to BG 36 and thus within the range of 280 to 390 kNm torque. As a result, it covers a very wide range of applications on site. Apart from classical Kelly drilling, the eBG 33 can be used for high-performance methods, for example soil mixing techniques such as cutter soil mixing (CSM) or double-head system drilling. It is even possible to attach a Bauer trench cutter.

In preparation for development of the electric drilling rig, analysis has revealed that the average diesel consumption is significantly higher for the BG 28 and larger equipment when compared to smaller equipment types. This is because this type of drilling rig is also used for high-performance methods roughly a third of the time, in addition to frequent Kelly drilling. “And this is exactly where we focused,” says Christian Heinecker. “In fact, our analysis also demonstrated that specifically in this range, the operating costs could be enormously reduced for the long-term operation of an eBG compared to a diesel-operated drilling rig.”

To deliver the same capacity as a conventional Bauer BG with a diesel engine, the eBG 33 was developed using a direct power supply solution. The reason: The currently available battery systems would not be able to manage the capacity in this size class. Accordingly, the preparatory work on site must be planned over a number of months to ensure that the power supply is also provided. Using the eBG is thus primarily advantageous on large-scale and long running construction sites, since the overall benefits, such as significantly reduced operating costs, can be fully exploited over the longer period of time.

From the outside, the eBG does not look any different from its “relatives” except for the color. It’s a different story on the inside: An electric engine was installed instead of the diesel engine and the power distribution is located where the tank would be. A transformer supplies various voltages for the electric control components. The engine requires a full 690 volts, while 400 volts are required for air conditioning and heating. In addition, a 230 V socket provides the option of plugging in additional attachment parts on site, such as percussion tools. The on-board controls require 24 volts as usual.

Starting with the transfer case, the structure of the eBG remains the same. The hydraulic system, control elements and software design are implemented in the established, conventional manner. The operator does not need to adapt because operating the equipment is the same as for all other Bauer BGs. The advantages of Bauer’s award-winning Energy Efficient Power (EEP) system are also fully available for the electrified eBG. The EEP system has been setting new standards for years now, especially in terms of emissions and diesel consumption. This concept also includes demand-specific, dynamic control of cooler speed and diesel engine speed as well as outstanding hydraulic efficiency thanks to large-scale hydraulic components. Another highlight is the operating method of the main winch: The EEP winch concept makes it possible to recover energy during retraction into the bore hole.

Cable guidance for a secure power supply poses a particular challenge. Once again, the idea comes from deep drilling technology: The solution is a power loop, a thick hose with a firm protective sheath inside of which a total of seven cables are laid.

At BAU ERLEBEN, the first eBG with a trailing cable is being presented. In this configuration, the equipment is primarily suited for soil mixing techniques where it operates in the same location for a considerable period of time. A model for Kelly drilling will be presented from mid-August. This machine needs to be able to move and rotate for alternating drilling and emptying operations. For that reason, this electric BG model is equipped with a patented cable guidance arm on the machine. “All in all, cable guidance will continue to pose certain challenges because every project has different requirements, and the solutions will be as diverse as the projects themselves,” remarks Christian Heinecker.

The eBG 33 is a novelty on the market in this form and capacity. “Development was possible due to close collaboration with our customers and above all due to the enormous dedication of our project team – we cannot thank them enough,” emphasizes Christian Heinecker. The team at Bauer Maschinen is thrilled that, with the eBG, one of the main pieces of equipment for specialist foundation engineering can now be operated completely CO₂-free on site. The eBG can execute various methods for the construction of excavation pit walls as well as drilling large-diameter foundation piles. Even the execution of cut-off bases is conceivable.

“During project preparation, the total initial expenditure is higher, but the customer can reduce overall operating costs thanks to the highly-efficient electric drive system,” summarizes Christian Heinecker. In addition, the total carbon footprint of a project is improved thanks to the CO₂-optimized electric drive system as well as the option of using CO₂-optimized construction methods. The implementation of many environmental initiatives and new regulations is thereby supported sustainably and with a view to the future.

Further informations:
BAUER AG
www.bauer.de

One of the largest gold deposits in the world is located on the volcanic island of Niolam, the main island in the Lihir archipelago of Papua New Guinea. The mine was discovered in 1982 and the sought-after precious metal has been extracted in open-cast mines for nearly 25 years – now reaching a depth of up to roughly 300 m below sea level. For a planned expansion of the mine, an impermeable protective wall is required around the new extraction area because of its close vicinity to the Pacific Ocean.

According to the plans, a 1.8 km long cut-off wall will be constructed as part of a seepage barrier structure and will advance into the geothermally active foundation with temperatures of up to approximately 150 °C at a depth of 60 m. This seepage barrier has two primary functions: Sealing off the new extraction area or open pit against ocean and ground water ingress by the cut-off wall and protecting the mine from immediate inrush of water to the open pit in the event of an extreme earthquake, causing liquefaction of foundation sediments and failure of the cut-off wall.

Due to the unique location of the mine in a geothermally active Lihir Island, Papua New Guinea, BAUER Engineering PNG Ltd., a subsidiary of BAUER Spezialtiefbau GmbH, Schrobenhausen/Germany, was commissioned by the owner Lihir Gold Ltd., a member of the Newcrest Mining Group, in collaboration with Klohn Crippen Berger (KCB) – Newcrest’s seepage barrier cut-off wall design consultant – to execute two test cut-off wall elements with three diaphragm wall panels per element up to a depth of 55 m below the ground surface (Figure 1). “For the first time in the history of diaphragm wall construction, cut-off wall elements are being constructed in geothermally active foundation conditions with ground temperatures between 120 and 150 °C,” explains Gebhard Dausch, Project Manager at BAUER Engineering PNG Ltd. “Standard equipment combined with a unique slurry circulation system cooled by sea water was used for the work – without customization or special technical protection of the Bauer equipment against the unprecedented high temperatures within the foundation.”

The work included the construction of a total of six diaphragm wall panels in two cut-off wall elements. All six panels were constructed through approximately 30 to 35 m of loose respective blasted mine waste rock fill consisting of fine and course soil, gravels, cobbles and boulders up to 2 to 3 m in diameter, underlain by 15 to 20 m of marine sediments consisting of silt and sand as well as 5 to 10 m of highly altered – by high temperatures – of volcanic rock.

Five panels were keyed into the volcanic soil strata at a depth of 55 m below the ground surface and one panel reached a depth of 60 m. To determine the temperature and electrical resistance in the concrete, reinforcement cages with temperature sensors and multi-ring electrodes were lifted into the cut-off wall elements. A grouted body was also constructed around the diaphragm wall by means of pre-treatment grouting to prevent two slurry loss and trench collapse of the panels, and a plastic concrete specified by KCB with a high temperature resistance was used. A BAUER MC 128 duty-cycle crane with BC 30 cutter unit, an MC 96 duty-cycle crane with grab unit and a -BAUER BG 45 drilling rig with double-walled casing are being used for this work. During the diaphragm wall works, a special cooling unit developed for oil drilling is used along with the usual equipment. The heated bentonite flows through this mud cooler, thereby cooling back down to ambient temperature.

The work process speaks for itself: The hot soil respective rock cuttings are taken up into the cutter box then conveyed together with the bentonite suspension to the desanding plant, so that the bentonite suspension provides both cooling and insulation. Thanks to the addition of fresh bentonite in the trench, the slurry flowing down to the cutter cools the diaphragm wall panel. Even after reaching the final depth, the constructed diaphragm wall panel only heats up very slowly, making it possible to carry out installation of the reinforcement cage and the subsequent concreting works without significant risk for the employees.

Work by BAUER Engineering PNG Ltd. began in September 2020 and concluded in April 2021.

Further information:
BAUER AG
www.bauer.de

Red Dog Mine, one of the world’s largest zinc mines, is located in the north-west of Alaska, around 170 km north of the Arctic Circle and nearly 1,000 km to the north-west of Anchorage. The mine has been operating since the late 1980s with around 10 % of the world’s zinc extracted here in open-cast mining.

Its location in the Arctic Circle region means that the entire mine is in a geological permafrost area that keeps the ground permanently and completely frozen below a certain depth. There is an active zone near the surface that thaws during the summer and refreezes during winter. Based on an evaluation of the permafrost and soil on the site, ground improvements were identified as a prudent measure to counteract the effects of potential melting permafrost. To this end, BAUER Foundation Corp. was tasked by Teck with carrying out field tests using the jet grouting and Cutter Soil Mixing (CSM) methods (Figure 1).

“The trials included detailed data capture and strict quality controls in close collaboration with Teck, the project owner, and other geotechnical consulting engineers,” explains Alejandro de la Rosa Knecht, Project Manager with Bauer Foundation. “Trials were carried out from August to December 2019, which ultimately identified the CSM method as the most suitable choice for the main scope of this project.” The CSM method combines features of the diaphragm wall technique and the mixed-in-place ground improvement method (MIP). The soil is broken up using a cutter, then rearranged and mixed with an aggregate. The trials for the Red Dog Mine also determined the extent to which existing subsoil was to be replaced with suitable filler material to facilitate later mixing.

In 2020, during the period from July to November, 50 % of the pre-drilling was completed as well as 30 % of the CSM. In addition, BAUER Foundation Corp. was tasked with the construction of a secant pile wall as an extension to an existing slurry wall. To achieve this, the required pile wall was integrated into the existing slurry wall and the underlying rock using primary and secondary piles. In all, 93 secant piles were constructed. A multi-purpose BAUER BG 30 drilling rig with special Arctic equipment along with various drilling tool and mixer sets were used for the execution of all the works.

One of the main challenges was the mobilization of equipment in the limited time provided by the schedule. However, the required special equipment was mobilized in record time.

Some equipment was transported by plane and then by ship from Seattle Harbor across the Bering Sea to a dock just over 80 km from the mine. Other equipment was transported via Hercules aircraft from Anchorage airport to the airport on the mine site. This logistical success was made possible by close collaboration with various Bauer subsidiaries and Teck. “The remote and isolated location, the long deployment times and accommodation in camps pose additional challenges, as do the extreme Arctic climate conditions, precautionary measures associated with the corona pandemic and the specific safety requirements of the mining industry,” says de la Rosa Knecht.

Despite all these challenges, the Bauer and client teams were able to successfully conclude trial work between August and December 2019 and the first phase of production activities between July and November 2020. The final production phase which includes CSM and demobilization was completed by June 2021.

Further information:
BAUER AG
www.bauer.de