Environmental protection at Lünen

The Lünen site is an important recycling center of Aurubis AG.

With a production capacity of about 250,000 t of copper cathodes per year, the plant, which is just one kilometer away from Lünen Town Hall, is one of  the world’s largest secondary copper smelters.

Around 650 employees produce copper anodes, copper cathodes, iron silicate sand and a variety of co-products here on 316,000 m³ of premises.

The site has the capabilities for flexible secondary raw material use and, as a multi-metal recycling site, is able to process highly complex raw materials in its own smelting and refining processes.

Besides traditional materials such as copper scrap and alloy scrap, sludges and industrial residues, recycling raw materials also include complexly composed materials such as reprocessing fractions from electrical scrap and end-of-life vehicles as well as waste incineration ashes.

Improvements and investments in environmental protection are also of great importance in Lünen. Around €130 million has been invested in environmental protection since 2000.

With the commissioning of the Kayser Recycling System at the Lünen site in 2002, Aurubis became one of the world's largest copper recyclers and set new standards in environmental protection with exemplary character.

In the subsequent years, many more investments were made in environmental protection, especially to reduce fugitive emissions in the metallurgical facilities and in the storage and handling of input materials. The emission reduction concept initially agreed with the authorities and estimated at €10 million was extended with additional environmental protection investments of €25 million.

But also in the water sector, the Lünen site is continiously developing. The facility for water retention, treatment and use of surface water – in short “RAN facility” - operated with a total investment volume of around €4.5 million, enables more than 100,000 m³ of treated rainwater to be used for internal purposes as process water and thus saved every year. The plant is continuously improved. Optimized water collection and delivery has already reduced the amount of water knocked down by 50% compared to 2019. To further improve sustainable water use, new optimizations of internal water use are planned for the Lünen site in the coming years as part of a water concept. The aim is to use all water internally as far as possible and to avoid discharging wastewater into the public sewer system.

The efficient use of natural resources such as water has been part of Aurubis' corporate culture for many years and is also an important part of ecological and economic responsibility for the Lünen site.

The efficient use of natural resources also includes energy and the reduction of CO emissions. Innovative projects to increase energy efficiency ensure highly efficient and flexible power generation from waste heat at the Lünen site by means of cogeneration via a two-stage condensing turbine.

Up to 23 million kWh of electricity (around 14% of the site's electricity requirements or the average electricity demand of around 6,500 three-person households) can be generated and at the same time up to 14,000 t of CO2 avoided each year. The German Energy Agency's Energy Efficiency Initiative rated the project as exemplary and awarded it the Best Practice Energy Efficiency label in 2015.

Aurubis considers the protection of biodiversity as one of the major environmental challenges of our time. Therefore, biodiversity has also been one of Aurubis' environmental targets for several years. Since the plant site in Lünen is located only a few kilometers from several Natura 2000 nature conservation areas, it is important for the site to maintain and promote good conditions in the plant environment for species protection and biodiversity. As a matter of principle, the potential impact on biodiversity and the possibilities for promoting biodiversity are examined for every construction project or project.

The environmental management system at the Lünen site, which has been certified to EMAS and ISO 14001 since 1997, ensures that production and environmental protection targets are met and that development opportunities can be optimally exploited. Together with the quality management system certified to ISO 9001, the energy management system certified to ISO 50001 since 2013 and the occupational safety management system certified to ISO 45001 since 2021, they form an integrated management system (IMS). The external audits carried out as part of the certification of the management system include a review of environmental data, compliance with legal requirements and the effectiveness of operational processes.

Detailed environmental information on the Lünen site can be found in the current Environmental Statement.

Environmental Protection - facts & figures
Dust emissions

Dust emissions in g/t of copper produced

Dust emissions per ton of copper produced have been reduced by around 79 % since 2000.

Copper emissions

Copper emissions in g/t of copper produced

Copper emissions per ton of produced copper have been reduced by about 89% since 2000.

With cathode copper production more or less unchanged, metal production is generated from a high and increasing input of complex and low-copper recycling raw materials. The average copper content in the raw materials is decreasing, and the content of by-metals such as zinc, tin, nickel, gold and silver is increasing significantly. The increasingly complex composition of raw materials is becoming more energy-intensive to process.

Energy awareness is now incorporated into the regular qualification/instruction of employees. In particular, as a statement in the 2022 energy crisis, some consumers were switched off, such as lighting of outdoor facilities, provided this does not affect safety or environmental protection. An alternative to natural gas supply was also planned in the shortest possible time due to the European war events in 2022 - The Lünen plant plans to commission an LPG plant in December 2023.

Energy consumption

Specific energy consumption [MWh/t secondary raw material input]

By commissioning the new bath melting furnace in 2002 and the TBRC (Top Blown Rotary Converter) in 2011, we were able to significantly increase our energy efficiency. The specific energy indicator in relation to the input of recycling raw materials illustrates in concrete terms the strategy of multi-metal recycling chosen for the Lünen site. With more or less unchanged cathode copper production, metal production is generated from a high and increasing input of complex and low-copper recycling raw materials. As the average copper content in the raw materials decreases, the share of by-metals such as zinc, tin, nickel, gold, and silver increases significantly. The trend reversal in 2014 shows that the increasingly complex raw materials are becoming more energy-intensive to process.  

Environmental Protection Measures & Projects
Reduction of air emissions

1. Assessment of the emission effects after closure of the smelting operations hall and, if necessary, closure of the KRS roof ventilation.

  • Measures are discussed and prioritized together with the authorities (closure of the ridge turrets, storage halls, etc.)

2. Implementation of the measures identified by drone measurements in the anode furnace area: sealing of Kesselhaus 7, water spraying on the roof in the casting area.

  • The measures were implemented and accepted by the authorities in 2021.
Improvement of odor immissions in the plant surroundings

Next steps:

  • New filter system being installed in the sampling hall.


  • Filter to be commissioned in summer 2023.

Optimization of the water flows

Next steps:

  • Separate treatment of the remediation water and improvement of the ratio of utilized to discharged surface water close to 100 %.


  • The previous goals have been achieved. An internal water use concept is currently being water utilization concept is being developed, which should completely avoid the discharge of unused service water.

Increasing energy efficiency

1. Heat utilization and water quality of the anode smelter circuits, and the leaching plant are optimized to increase performance

  • Concepts are in developed with external support. Projects are included in the investment budget.

2. Increasing the direct use of heat from waste heat: Construction of a steam storage plant for optimized steam utilization. The steam storage facilities are intended to minimize energy losses and ensure an optimized supply of process steam to the boilers and plants.

  • The project is in the basic engineering stage. Annual savings of 32,000 MWh natural gas and 6500 tCO2

3. Efficiency increase KRS

  • Annual savings of 36,400 MWh of oil and 10,000 t CO2
Transition to the requirements of the Seveso III Directive


  • Public disclosuret


  • The documents are accessible on the internet, the visitor and external company instructions have been revised. A general guideline on conduct and clothing regulations has been established for employees and external companies/visitors and are part of plant briefings.

Organizational improvements

Next steps:

  • Results improvement projects and project organization 


  • The system for the continuous improvement of procedures and processes (AOS) was merged organizationally with the Integrated Management System.

Environmental Protection milestones at Lünen site

As part of a new water concept, further improvements are planned with regard to sustainable water use. Further optimization of internal water use is planned for the coming years, including further treatment of internal process water (reverse osmosis, evaporation). The goal is to use all water internally as far as possible and to completely avoid discharging process water into the public sewer system. Implementation of the project is scheduled for 2023/2024.


The Aurubis sites in Hamburg and Lünen have successfully completed the certification process by the Copper Mark and now bear the recognized seal of quality for sustainability in the copper industry. The Copper Mark is the seal of quality for sustainability in the copper industry. Since March 30, 2020, mines and smelters have been able to verify their sustainability performance on a voluntary basis and have it verified by third parties. Currently, more than 40 sites have joined the Copper Mark. A pilot project is currently underway with companies in downstream copper processing. The certificate for the Hamburg plant already includes this processing step. The 32 sustainability criteria of the Risk Readiness Assessment from the Responsible Minerals Initiative (RMI) on topics such as compliance, child labor, environmental protection and occupational safety apply to the Copper Mark. It is aligned with the Sustainable Development Goals (SDGs), the United Nations framework. For the criterion of responsible sourcing of copper, lead, nickel and zinc, the Copper Mark has also developed a due diligence standard that also serves to meet the standards of the London Metal Exchange (LME), one of the world's most important metal exchanges, for responsible sourcing of metals. In addition to the Copper Mark, the Lünen site also bears the Zinc Mark and Nickel Mark quality labels.


Start of the modernization of the tankhouse. Aurubis AG is investing a total of € 60 million in the renewal of the plant over the next four years. The work includes the demolition and new construction of the tankhouse basins, and the efficiency improvement of the plant will increase the capacity by about 10 %. During the modernization in sections, the plant will remain in operation with an 80 % capacity. In April 2019, the electrolysis renewal project was initiated. The first phase was completed in early 2020.

In 2022, the entire roof ridge turret of the electrolysis was renewed during the overall renovation.


Commissioning of a two-stage steam turbine (5.7 MWel) to use up to 300,000 t of process steam for internal energy generation and use.


Conversion of the plant's mixed sewer system into a separate sewer system (operational wastewater, sanitary water, and rainwater) in connection with rainwater retention and collection (RAN system, 9,000 m3 retention volume). This enables the use of collected rainwater as internal service water for cooling processes and thus a savings of more than 100,000 m3 of water drawn from the public supply.


Complete closure and extraction of the smelter hall. As a result of this measure, the entire melting processes of the Lünen plant, from the bath melting furnace to the anode furnace, including the halls for transport and charging, have been completely exhausted. Emissions from the site have thus been minimized far beyond the state of the art.


Commissioning of a converter furnace (TBRC) as part of the KRS+ efficiency project. As a result of this process technology improvement, the Lünen site was able to increase its throughput by more than 30 % while maintaining the same overall primary energy input for the plant.


Installation of a truck tire washing system, which all delivery vehicles must pass through before leaving the factory, to further minimize dust emissions from the factory.


Construction of a noise protection barrier at the material delivery in the southern area of the plant to reduce noise emissions from delivery traffic on the adjacent properties.


Implementation of the Kayser Recycling System (KRS) in the course of the plant modernization after the takeover by Aurubis AG (then Norddeutsche Affinerie AG). Commissioning of a highly efficient ISA bath melting furnace and a tin composite furnace with state-of-the-art filter technology to replace the site's old shaft furnaces.

Download (PDF)
Your Contact
Andreas Nolte
Andreas Nolte

Leiter Allgemeine Services Aurubis Lünen, Qualitäts- und Energiemanagement

Phone +49 2306 108-244
Send e-mail