Circular economy: alive and well at Feralpi Stahl

Giuseppe Pasini, President of the Feralpi Group (Photo: Feralpi)

Author: Angela Layendecker

In the German town of Riesa, the home of steel company Feralpi Stahl today, around 24 million tonnes of scrap have been turned into steel for productive use since the business was founded in 1992. The steel produced by Feralpi is made from almost 99% recycled material. With this process, the German company plays an important part in supporting a circular economy, keeping the consumption of natural resources (such as iron ore) at a low level and preventing waste iron from entering the natural environment. The company’s strategy, which is geared towards sustainability, is intended to endure over the long term. For this reason, several investment projects have already been launched – all with the aim of producing steel even more efficiently and sustainably.

“Improving our carbon footprint is one of the primary goals of Feralpi’s ESG strategy”, explains Feralpi Group Chairman Giuseppe Pasini. “We have set out clear environmental performance indicators for the 2022–2026 financial years with a harmonious combination of sustainability and competitiveness. This investment is part of a far broader action plan designed to ensure the continuity of our responsible business development and the creation of value for our market and our stakeholders.”

Laser-focused Investments in the future

Feralpi Stahl has earmarked around €200 million as an investment package for the next four years. All of this is for its green steel. The Riesa-based company has taken various steps within the circular process of steel production and processing to try to minimise harmful substances to the point of virtual undetectability, as well as to reduce emissions levels. The measures include scrap processing, energy efficiency, building a circular economy and embracing digital transformation.

Feralpi Stahl site (Photo: Feralpi Stahl)

Less harmful substances in the production process

One of the investment projects in the coming years will focus on using scrap as a raw material for steel production. A number of shredding and separation facilities working in close coordination separate the scrap material and clean away dirt or residue. This significantly increases the quality of the scrap and homogenises piece sizes.

Dr Mathias Schreiber, head of the integrated management system at Feralpi Stahl: “Our improved scrap processing also increases our scrap density. Along with automated scrap basket loading, this leads to a much more stable loading process and lower resource consumption. This optimised process of filling the electric furnace has allowed us to go from transporting three scrap baskets at once to two – and reduces the energy losses during scrap use.”

As a result, less filter dust and slag are produced in the steel mill’s production process. At the same time, the process minimises the introduction of harmful accompanying elements, such as heavy metals and organic pollutants, into the melting furnace. Non-ferrous metals can be separated from the materials that cannot be used during scrap sorting, allowing them to be put to productive use in turn. The enclosure around the entire system also leads to lower dust and noise emissions.

Electric furnace: 115 tons of scrap are turned into approx. 110 tons of liquid steel per batch (Photo: Feralpi Stahl)

State-of-the-art dust removal systems filter the untreated gases from the electric furnace via direct extraction and the dust from the production facility via secondary extraction. The environmentally friendly process designed by Feralpi Stahl for effective off-gas treatment has been included as a best available technique on the EU’s BREF list. With this method, pollutants in the off-gas can be reduced to a low, environmentally sound level.

Putting waste heat and water to good use

The steelworks uses the waste heat generated by direct extraction from the electric furnace to generate its own electricity and supply steam to a nearby tyre plant. The waste heat from the air compressors is used for heating the office buildings and for hot water treatment. Almost 20 GWh of electricity and steam were recovered in 2020 alone thanks to energy recovery from the electric arc furnace.

With improved circular use of the cooling water and the use of rainwater, the company minimises its consumption of public water, thus conserving natural resources. Less than 4% of the cooling cycle water is discharged as wastewater for desalination, meaning that more than 96% of the water is recovered and reused.

The new scrap processing plant (Photo: Feralpi Stahl)

Hot rolling Efficiency

The rolling mill also makes lower-emission production possible by hot-charging cast billets from the steelworks, which reduces natural gas consumption by the elevator furnace. As a result, the steel billets do not cool down too much or need to be reheated.

The new, energy-efficient spooler hot rolling mill, which is due to start production in 2024, will be able to process the steel that is now being produced in greater volumes. Steel production will increase from approximately 1 million to 1.3 million tonnes per year. And a new product has been created in the form of directly coiled rebar, which involves processing the steel using thermomechanical rolling, or soft quenching, yielding high-quality material. Conventional cold working involving stretching and spooling is no longer employed.

The method of billet welding used allows for virtually endless rolling, ensuring a stable process with low waste. Similar to the old rolling mill, the billets are also hot-charged here, which saves energy by using 100% of the residual casting heat. The hot billets are transferred from the continuous casting system via a 300-metre-long, thermally insulated roller conveyor directly into the new hot rolling mill, where they are reheated and processed further.

Uwe Reinecke, plant director at Feralpi Stahl: “The billet welding and spooler line allow for a 2.5 to 8-tonne increase in coil mass, creating an almost 5% increase in material efficiency and more than 5% increase in energy savings.”

An inductively heated furnace for the continuous casting material is to replace the gas-fired furnace. This will also give Feralpi Stahl the opportunity to use renewable energy for production with zero CO₂ and NO_x emissions in future.

Uwe Reinecke: “Inductive reheating significantly reduces energy consumption as well as emissions of CO₂ and nitrogen per tonne of end product. We will save around 80% of the energy that would have been used in conventional reheating with gas from 850°C to 1,050°C. As a result, CO₂ emissions can be reduced by about 30,000 tonnes a year.”

Uwe Reinecke, Director at Feralpi Stahl (Photo: Feralpi Stahl)

Energy Connects

The energy source used is one of the key factors in the move towards green steel, and the facilities in Riesa, Germany, are planning to replace natural gas with hydrogen in the future. For this reason, Feralpi Stahl and seven other local industrial companies set up the EWI network in 2002, an energy and hydrogen alliance in the district of Meissen. As the first result of the collaboration, the planned hydrogen pipeline in Saxony will now be built closer to the Riesa facility and the Meissen district generally, along with the companies that operate within it.

Hydrogen use is currently also being tested at Feralpi Stahl’s plant. There is a conceivable possibility of connecting the EWI pipeline to the hydrogen line planned by the state government via an appropriate connection point by 2027. If these actions are taken, there could be a further significant reduction in the plant’s CO₂ emissions.

Uwe Reinecke: “We are trying to counteract the high energy prices by embracing energy efficiency and intelligent operation modes. However, the transformation of steel plants in Germany’s small and medium-sized sector can only succeed with financial support from the state and federal governments.”

Waste Recycling

However, as well as focusing on the production, processing of and energy supply for steel products, the company’s sustainability action plan also encompasses the process’ waste products. Under the label of SteelZeroWaste, Feralpi brings together its activities intended to reduce the amount of waste at the site to a minimum and direct unavoidable waste into the circular economy.

Significant portions of waste and production residue, such as more than 50% of the furnace slag, can be recycled. For example, the construction sector can use furnace slag, which is 100% recyclable, instead of consuming natural materials. Thanks to its high zinc content, the filter dust obtained from flue gas treatment can also take the place of natural ore.

Similarly, the mill scale with its almost 100% pure iron oxide can be used as a substitute for iron ore. This green iron is used in the cement industry and in plants for the production of calibration weights. And finally, the refractory material from the ladle furnace can also be returned to the production loop as a slag former in the arc furnace after its use as a raw material.

Digital control

The effectiveness of emission and waste reduction in steel and rolling mills can be increased even further using automated processes and artificial intelligence. As well as being monitored by sensors, the temperatures throughout the production process are also precisely set in advance and met with recommendations in real time.

This reduces temperature fluctuations to a minimum and stabilises the production process, from steel production to continuous casting. Thanks to artificial intelligence, the new rolling mill can share data with the existing rolling mill to control the production process and monitor product quality online on an ongoing basis. As a result, this digital transformation makes reduction of the temperature level possible across the entire production set-up.

Changes in infrastructure

The planned activities, especially when combined with the new rolling mill and scrap processing, require large parts of the plant premises to be converted. The process of improving steel production and processing must ensure an optimised workflow.

For this purpose, derelict and former production facilities are to be brought back to life – the expansion of process-supporting peripheral systems, such as those for energy and water, is intended to supplement the current infrastructure. Among other things, a new pumping station and substation with gas-insulated switchgear are being built on the site. As well as being another important factor in ensuring supply reliability, the new substation is also low in CO₂ emissions, making it more sustainable than comparable installations.

The work behind "made in Riese"

Investments in green steel are not solely focused on the product and infrastructure, although this is probably where the transition to a sustainable and green business can be seen most clearly. The investments in the industrial location also create a noticeably closer link between the company and its surrounding communities. With over 730 staff members, the business is currently one of the largest employers in the region.

And still more people are needed who want to experience the same growth trajectory as the green Feralpi steel. New jobs already await – over the next four years, more than 100 new positions in a wide variety of occupational fields will be created in this rural area of Germany. Contemporary staff facilities are also being planned on the site, which are intended to make people’s working lives more comfortable in the steel business. This is a guiding principle of the Feralpi Group, which wants to see innovation put into practice – not only for technology, but also for people.

Uwe Reinecke: “A shift is not only being brought about by our energy and location changes. Most of all, it is being brought about by our people. Only with a dedicated team – one that is flexible, sticks together and takes an innovative approach – can transformations like this be made a reality.”

Ten years of transformation culminating in green steel made in Riesa:

2012: EMAS certification – highest EU eco-label (consecutively issued until 2022)
2013: State of Saxony’s Environmental Award for the steam and energy generation system (waste heat utilisation)
2014: Feralpi starts direct charging continuous casting billets in the existing Rolling Mill A
2015: Use of the magnetic drum for sheared scrap processing
2018: Start of scrap logistics optimisation
2018: Admitted to Klimaschutz-Unternehmen e.V. excellence initiative for businesses taking climate action
2020: Emissions reduced in Feralpi’s logistics thanks to new vehicles
2021: Construction of enclosed facility for scrap logistics (receiving, processing and outward transfer)
2022: EWI (alliance focused on energy and hydrogen in Meissen industrial district) set up
2023: New scrap concept and enclosure completed, phase I