RAG

On 31th December 2005, the Lohberg mine belonging to RAG Aktiengesellschaft, Essen/Germany, was closed down. Around 1,400 employees were transferred to other mines or took early retirement. In 2017, the rope sheaves were dismantled for refurbishment. In 2021, the entire shaft frame itself was scaffolded in order to renovate it as well. Now the cable sheaves are being reinstalled. This is a very complex undertaking (Figure 1).

The bottom two of the four sheaves are not making it easy for the fitters. They are lifted with a powerful crane to the top floor of the approximately 70 m high shaft frame. There they are then “re-attached” to a chain that is bolted to a correspondingly designed beam on the crane runway platform (the upper edge). The crane then enters this crane runway again. It picks up the rope sheave again and sets it down on the mounting points of the lower rope sheave platform. The same is done with the second rope sheave. The two upper sheaves are hoisted directly through the crane runway and placed on the upper rope sheave platform. For this, the height rescue team is also deployed in addition to the cranes.

Over the next few years, the two Lohberg shafts and the shaft in Hünxe will be prepared for pumping mine water. To do this, the shafts will be filled in and at the same time equipped with casing pipes through which the pumps will then be lowered into the depths: three casing pipes each on Lohberg 2 and under the already dismantled Lohberg 1 headframe, and four more in Hünxe. This ensures that sufficient pumping capacity is always available. The planned start of pumping is scheduled for 2032. Then, a total of around 33 M m³ of mine water will be discharged into the Rhine every year.

Stefan Roßbach, head of department at RAG-Grubenwasserhaltung: “Lohberg is an important mine water site for us. From here, all the mine water from the Emschermulde basin flows into the Rhine. Lohberg was an important mining location for a long time. It will continue to be important in the post-mining era. Here we can present the entire RAG portfolio: in addition to mine water management, e. g., the development of areas for new uses, including the generation of renewable energies.” (RAG/Si.)

After around 15 months of construction, the first section of the 7.4 km-long mine water channel has been driven. The breakthrough after 3.2 km marks an important milestone for the long-term water drainage in Ibbenbüren.

“Today is a special day for RAG. We have completed the first stage of the mine water channel. My thanks go in particular to the miners involved. Of course, this is not the first breakthrough we have experienced here today. But this one here at the Miriam tunnel is a milestone for RAG” emphasised RAG CEO Peter Schrimpf. “This is an immensely important project for us; we will never pump water here, which is an ecological innovation.”

The innovative character of the long-term water drainage at the Ibbenbüren site is part of the mine water concept of RAG Aktiengesell­schaft, Essen/Germany. In Ibbenbüren, the mine water will be able to be conducted into the mine water channel without pressure – i. e. without the use of energy. After the mine water has risen to 63 m ASL, no pumps will have to be operated, as in the Westfeld. This means a significant improvement in water quality and energy savings. “On a day like this, you feel proud. A breakthrough with this precision is an uplifting moment. We have been working on this project for over ten years, so the breakthrough at the Miriam tunnel is very special,” said Jürgen Kunz, head of the RAG Ibben­büren division.

The breakthrough was eagerly awaited: the tunnel boring machine, christened “Barbara”, reached the centre shaft of the mine water channel at a depth of 73 m, exactly on target. This impressive moment was honoured by Schrimpf, Jürgen Rupp, CFO of the RAG Stiftung, Essen, and Kunz. Also present were the godmother of the western section, Miriam März, Head of the Human Resources & Development Division of RAG, and the employees of the Ibbenbüren Division of RAG who were involved in the project, as well as the project partners of the ARGE Tunnelbau consortium and representatives of the Arnsberg district government (Figure 1).

“This is my eighth breakthrough to date. You’re always afraid that you won’t hit it. And then it works down to the millimetre. Tunnel construction is an absolute team sport, it only works together. We are very happy today,” said Rukan Mengü, Tunnel Construction Manager, Shift Engineer at Wayss & Freytag Ingenieurbau AG, Frankfurt/M. in Germany.

The Miriam tunnel that has now been driven will enable the mine water from the eastern and western fields of the Ibbenbüren mine to be fed into the new mine water treatment plant in Gravenhorst, which is currently under construction. The breakthrough of the east drive is planned for December 2024. The mine water currently rising in the eastern field is not expected to reach the surface until spring 2026 at the earliest. (RAG/Si.)

The Saarland Ministry of Economic Affairs, Innovation, Digital and Energy (MWIDE) and RAG Aktiengesellschaft, Essen/Germany, with its subsidiary RAG Montan Immobilien want to join forces to expand renewable energy in Saarland. Minister of Economic Affairs Jürgen Barke and RAG Board Member Michael Kalthoff signed a Letter of Intent (LOI) to this effect on 17th November 2023 (Figure 1).

In recent decades, Saarland has transformed itself from a coal and steel region to a multi-faceted industrial and service location with an international focus. In this context, the move away from fossil fuels and the expansion and strategic promotion of renewable energies are key steps towards making Saarland not only crisis-proof but also future-proof. The success of the energy transition and the green transformation of companies is therefore a key function for the Saarland as a business location.

RAG is contributing to the LOI by examining its own areas for the expansion of renewable energies. After covering its own requirements, around 25 ha are currently to be made available for electricity production for commercial enterprises in Saarland. RAG will seek to cooperate with Saarland companies in the development and realisation process. Space, area and operating data will be exchanged with the state, associated organisations and scientific institutes. Best-practice solutions for the future planning and construction of renewable energy plants are also to be developed and considerations on citizen participation orientated towards the common good are to be promoted.

The MWIDE provides technical and political support for these processes. On the one hand, the aim will be to focus on legal requirements in the planning and realisation of renewable energy projects at an early stage and to implement these quickly. On the other hand, questions and dialogue on ways to speed up procedures and measures are also part of this. Various event formats are to be organised and supported in order to jointly promote the implementation of renewable energy projects to the public.

Kalthoff is looking forward to working with the ministry: “The RAG Group has a significant portfolio of conversion sites in the Ruhr and Saar regions and we are happy to support the plans to expand renewable energy. RAG wants to make a sustainable contribution – to regions worth living in, which are also home to the company. This is also an important part of our corporate strategy. In future, we will also cover our energy requirements for the operation of our water storage and administrative sites with our own green electricity. Our aim is to be CO₂-neutral by 2030.”

Barke: “Due to our historical, industrial structure, we in Saarland are particularly affected by the green transformation. Saarland is also very densely populated and the competition for land is clearly noticeable. We Saarlanders are no strangers to change. We have learnt to see it as an opportunity. Against this backdrop, I am delighted that we have succeeded in initiating a cooperation that will accompany both the state and RAG into the future. The energy transition, with its many and varied requirements, is essential for Saarland – it is the prerequisite for our economic future and the preservation of the location. Joint models and projects between the state and companies like this are needed. I would therefore be delighted if our cooperation were to set a precedent.” (RAG/Si.)

After intensive preparations, Iqony Energies GmbH, Saarbrücken/Germany, a subsidiary of the energy company Iqony GmbH, Essen/Germany, has decided to modernise and convert its existing district heating generation plants and district heating network on the site of the former Camphausen mine into an innovative and climate-neutral heat generation system (Figure 1). Waste heat from mine water from RAG Aktiengesellschaft, Essen/Germany, will be tapped as a new heat source and made available for the district heating supply to the town of Sulzbach. This will avoid annual CO₂ emissions of more than 6,000 t in the future.

The project had already received funding approval in December 2020 as part of a tender for “Innovative CHP energy systems” (iKWK) from the Federal Network Agency. Combined heat and power (CHP) plants generate electricity and heat at the same time and are therefore particularly efficient and resource-saving. However, extensive preliminary planning, many technical challenges and regulatory decisions in Berlin meant that the project could not yet be realised. Now, however, all the requirements have been met and realisation can begin.

In technical terms, the project consists of three coordinated components: a conventional CHP plant, the renewable heat source in the form of mine water and a heat pump that utilises the residual heat of around 36 °C contained in the mine water for the district heating supply.

“We are delighted to be able to help make a climate-neutral contribution to the heat supply with the mine water that we provide to Iqony. This mine water has a temperature that can definitely be used to generate heat,” says Michael Drobniewski, RAG Regional Representative for Saarland. Appropriate feasibility studies are therefore being carried out at all mine water drainage sites.

“Pumping the mine water naturally makes it much easier to tap into this ­unusual source of heat,” explains Dietmar Bies, who is responsible for the project on behalf of Iqony. The heat obtained in this way ensures a corresponding reduction in the use of conventional energy sources, meaning that the Camphausen CHP plant saves around 6,300 t of CO₂ emissions every year.

Because the third part of the plant, the conventional CHP plant, is also fuelled by an energy source classified as climate-neutral, the plant as a whole is already completely emission-free.

Anke Langner, CEO of Iqony Energies: “We use mine gas as fuel in the conventional CHP plant, which has a high methane content. When released into the atmosphere unburnt, methane is more than twenty times more harmful to the climate than CO₂. Accordingly, politicians have only recently confirmed the ice classification of mine gas as a climate-neutral fuel, which is why the use of mine gas as a fuel is also a sensible measure in the interests of the climate.”

What’s more, there will still be sufficient fuel available in the coming years. However, the legal categorisation of mine gas as an energy source was in limbo in the political debate for a long time. As a result, the realisation of the project in Camphausen also took longer than originally planned.

For the users of district heating in the municipalities of Camphausen and Sulzbach, including a hospital and industrial and commercial enterprises, this in turn means that the district heating supplied in future from the plant on the former colliery site is already green, i. e., climate-neutral.

It is not only against this background that Stadtwerke Sulzbach, as the local district heating supplier, and Iqony Energies have decided to continue their proven and successful collaboration and extend the corresponding cooperation agreement by 20 years. “We are delighted that we are continuing our cooperation and at the same time opening a new, climate-neutral chapter for the local heat supply with the conversion of the plant in Camphausen, which is now beginning,” says Langner. And Iqony has another piece of good news to report to the citizens of the two municipalities: “From a technical point of view, our plant still has potential to increase the generation of green heat. This means that nothing stands in the way of a possible expansion of a truly climate-neutral district heating supply on the generation side,” says Langner.

Construction work began in October 2023 and will take around 14 months. The plant is expected to be commissioned at the end of 2024. During the conversion phase, the supply of heat to the communities will be ensured at all times by means of mobile heating centres. (Iqony/RAG /Si.)

Tisa – this will be the future name of the tunnel boring machine that will drive the mine water channel from the central shaft to Oeynhausen’s shaft 1. The name was given to the Dorsten artist Tisa von der Schulenburg, who was closely associated with the hard coal mining industry. She not only thematised mining artistically, but also distinguished herself through a high degree of solidarity with the miners.

During a festive ceremony on 4th August 2023, the second tunnel boring machine for the construction of the mine water channel of the former Ibbenbüren mine of RAG Aktiengesellschaft, Essen/Germany, was symbolically christened by Pastor Andreas Finke and Pastor Paul Konnadur at the central shaft of the mine water channel (Figure 1). It is the second tunnel boring machine to be used for the construction of the mine water channel. It will drive a length of 3,867 m in the east section. In future, the mine water from the Ibbenbüren mine will be fed via the mine water channel to the new mine water treatment plant currently under construction in Gravenhorst.

Peter Schrimpf, Chairman of the RAG Board of Management: “The excavation of the mine water channel in Ibbenbüren is a very special project for us in many respects. It is, so to speak, the last excavation in the German hard coal mining industry. It is also an outstanding project in terms of investment volume. And it is a prime example of sustainability and the environmentally friendly handling of mine water. I wish us all continued success with the project. Above all, I wish everyone involved on the construction site good health. Occupational safety and the integrity of our employees and partners is and remains an essential element of our corporate culture.”

The channel is scheduled to be commissioned in 2025. (RAG /Si.)

Currently, the final operating plan procedure for the termination of the mining supervision for the former Proper II shaft (Figure 1) of the former Prosper-Haniel mine in Bottrop/Germany is underway. Within the procedure, an “orienting hazard assessment” was carried out. The expert recommends prohibiting groundwater extraction there due to the sometimes significant groundwater contamination in some areas. The city of Bottrop has therefore banned both the use and extraction of groundwater in these areas.

The groundwater in the downstream of the Prosper-Haniel mine was already sampled during the phase-out of operations. “We continued to keep an eye on the groundwater as part of the final operating plan procedure. For this purpose, there were measuring points both by us and by the city of Bottrop at Knappenstraße and in the adjacent settlement. Until autumn, the values measured there were only slightly elevated,” says Michael Otto of RAG Montan Immobilien GmbH in Essen, who is responsible for the final operating plan.

As part of the process, the number of groundwater measuring points on the site itself and in the settlement will be expanded step by step. In October, the values measured there were much higher. Otto: “We reported this to the supervisory authority and the city of Bottrop, which has now ordered this precautionary measure.” Essentially, the elevated values are coke ice-specific parameters.

The direction of flow of the groundwater is from east to west. Therefore, several causative factors are possible. Next to the colliery site, there was an old coking plant with various ancillary extraction facilities, such as a petrol factory.

Within the framework of the ongoing final operating plan procedure, solutions for a permanent safeguarding of the contaminated sites must now be developed and implemented so that a risk to the population can be excluded.

Groundwater remediation is already being carried out at several sites in the Ruhr area. Mostly at former coking plant sites that were destroyed in the Second World War. This is one of the eternal tasks in post-mining. (RAG/Si.)

The tunnel boring machine (TBM) eats its way about 340 m through the ground 10 m below the Datteln-Hamm Canal (Figure 1). Here, in 2025, mine water is to flow into the Lippe in a pipe. This is because Haus Aden is one of the central mine water sites of RAG Aktiengesellschaft in Essen. At the same time, a new residential area is being built here – directly on the water.

Due to the age of the former mine water pipeline and the future use of the Haus Aden water intake site as one of the remaining central uplift points in the Ruhr area, the mine water pipeline of the former Haus Aden colliery is being renewed as far as the Lippe. The mine water extraction rate is around 11.9 M m³/a. In order to use synergies, the existing flood water discharge pipe of the Oberaden pumping station will also be renewed in the course of this construction measure to ensure precipitation drainage.

The project will be implemented in two construction stages. The first construction phase comprises the renewal of the mine water drainage and the flood water discharge pipe between the former Haus Aden shaft site and Kleine Heide road north of the Datteln-Hamm canal. For this purpose, the canal will be crossed under with two media channels in which the pipelines will be routed. The second construction stage – extension to the Lippe – will take place afterwards.

With the current start of the tunnelling work, the first of the two media channels with an internal diameter of 3.20 m will be excavated. The length of the excavation is about 340 m and will be carried out from south to north. The excavation of the second media channel with a diameter of 2.80 m will start afterwards, also from south to north at the same depth. A period of about three months is planned for the tunnelling work for each media duct.
The start of the tunnelling measure, originally planned for spring/summer 2022, was delayed due to the clarification of legal issues that had to be accompanied by an expert opinion, as well as delivery problems with essential components. The completion of the entire project is scheduled for 2025.

The TBM from Herrenknecht has an installed capacity of 850 KW, is 7 m long and has a diameter of 4 m. The TBM can move up to 1.5 m per day. It can cut up to 10 m through the ground every day.

A Herrenknecht tunnel boring machine is used to excavate two channels for the renewal of the mine water drainage system and the flood water discharge pipe for the Haus Aden dewatering site. Photo/Photo: RAG

Barbara – this will be the name of the tunnel boring machine (TBM) in future, which will drive the mine water channel from the outlet to the central shaft (Figure 1). The woman who gave the TBM its name is the patron saint of all miners. Saint Barbara’s Day is therefore exactly the right temporal setting for the christening of this huge machine.

During a solemn ceremony on 7th December 2022, the first tunnel boring machine for the construction of the mine water channel of the former Ibbenbüren mine of RAG Aktiengesellschaft, Essen/Germany, was symbolically baptised by Parish Priest Andreas Finke and Pastor Martin Weber at the outlet of the mine water channel. It is one of two TBMs that will drive the mine water canal over a length of 7.4 km, through which the mine water of the Ibbenbüren mine will in future be fed to the new mine water treatment plant currently under construction in Gravenhorst.

The godmother of the first TBM of the west drive is Christine Wenzel, an internationally successful sports shooter from Ibbenbüren. Miriam März, head of RAG’s Personnel and Development Division (V-PE), will be the godmother for the west section of the mine water tunnel, which will be named “Miriam”.

With this act of blessing and symbolic baptism of the TBM and the tunnel, God’s assistance and blessing is requested for the safety and health of the tunnel builders as well as for the success of the project, which is being implemented to protect the people and nature in the former coal region.

A second TBM will be lowered into the 75-m-deep central shaft in the spring of this year and will dig its way through the ground from there in an easterly direction. In 2025, after completion, all the mine water will flow through the canal into the Gravenhorst treatment plant. (RAG/Si.)

At the future central Lohberg dewatering site of RAG Aktiengesellschaft, Essen/Germany, in Dinslaken, both the rehabilitation of the shaft frame and the development of the site area are showing visible progress (Figure 1).

In order to strengthen the double trestle, which is a listed building, reinforcement measures in the steel skeleton are necessary for structural reasons. In order to be able to carry out this work and the subsequent corrosion protection painting at dizzy heights, the scaffold, which is visible from afar and currently encloses almost the entire 74 m high headframe, was erected. The associated rope sheaves were removed beforehand and will be reinstalled in their original position once they have been refurbished. The work will continue into next year.

The area, which is under mine supervision, is currently being enclosed with a fence system which, with its clinkered posts and masonry elements and black fence lattices, blends harmoniously into the surrounding industrial landscape. “The Lohberg site will play a central role in RAG’s water retention concept in the future, as this is where the mine water from the entire Emscher syncline will be lifted using submersible pumps and discharged into the Rhine in a few years’ time. Planning for this will start next year,” explains Jörg Küsters, site manager for Lohberg. “Many coordination loops, especially with the Office for the Protection of Historical Monuments and the City of Dinslaken, were and are still necessary to meet all requirements,” adds project manager Harald Haase. (RAG/Si.)

Until now, the Velsen Adventure Mine Association) in the Saarland has leased the heritage site, formerly a training mine. In the last week, the Association, the RAG Aktien-gesellschaft,Essen/Germany, and the Saarland Ministry of Education and Culture have all signed the contracts (Figure 1).

The solution found is all thanks to a united commitment: As the new owner, the Association will bear any costs incurred for closure and filling. The RAG will therefore pay approximately 1.5 M € in closure costs, as specified in the decommissioning plan, to the Association, which will then transfer the money to the Saarland Ministry of Finance. The state has assured the Association that it will cover the costs in the event of an unavoidable closure and therefore also assumes the risk of increased costs in the future.

Stefan Hager, regional representative for the RAG, thanked all those involved for their extraordinary commitment and perseverance. “We are pleased to have found a viable and sustainable solution for everyone.” The former training tunnel will still be used, now as an Adventure Mine. “Velsen shows once more that it needs cooperation from everyone if the structural transformation is to be a success. With this in mind, we also hope to find solutions for the historical mining monuments. We wish the Velsen Adventure Mine Association many visitors, committed members and, in particular, all the “miner’s luck” in the future.” Volker Etgen, first Chairman of the Association, confirmed: “The transfer of ownership gives us planning security and the fate of this training mine, unique to Germany, will soon be in our hands.”

“Velsen offers more than just a glance at the past, it is indeed a place for future generations”, said the Saarland Minister of Culture Christine Streichert-Clivot while she signed the contracts. “We need networked services between the different mining and industrial heritage locations, and more professionalisation to support the extraordinary voluntary work in this sector. In the new budget, we must therefore also discuss increased funding for industrial heritage.”

Until 2011, the RAG was still teaching miners in the training mine. Since mining ended in the Saarland, the Association has used the training tunnel as a visitor mine. Across an 800 m stretch on three different levels, visitors can see powered shields in several longwalls, conveyors, transportation rails and drilling equipment. Particularly noteworthy: All machines and technologies used in active mining operations are available and ready for use.

A special moment for Minister Christine Streichert-Clivot. As the daughter of a miner, she feels personally drawn to the cultural legacy of the mining era and has in recent years worked with the volunteers of the Association and the RAG to find the chosen solution: “School classes are currently jumping at the chance to visit the former training tunnels in Velsen. Before the pandemic, the operators were swamped with bookings. Velsen offers more than just a glance at the past, it is indeed a place for future generations. We need networked services between the different mining and industrial heritage locations, and more professionalisation to support the extraordinary voluntary work in this sector. In the new budget, we must therefore also discuss increased funding for industrial heritage.” (RAG/Si.)