Trimet Aluminium SE is completing the expansion of its recycling plant in Gelsenkirchen, Germany. The project will increase production capacity at the site, as well as significantly reducing CO2 emissions by updating the energy supply. This will enable the company to achieve improved eco-balances in the aluminum alloys it produces from recycled scrap, benefiting the end products of the processing industry.
“To achieve climate goals, the industry needs sustainably produced materials,” said Dr. Andreas Lützerath, a member of the board at Trimet. “The demand for recycled aluminum will continue to rise. We are aligning ourselves with this demand by offering an expanded range of recycled materials and optimized ecological quality.”
The expansion involves the installation of an additional tilting rotary furnace and a casting wheel for aluminum sows, which increases melting capacity and improve energy efficiency. This is expected to increase the production capacity of Trimet’s recycling plant by approximately 20%, bringing production to 80,000 tons of recycled aluminum annually.
A significant portion of the extensive work on the expansion project focused on renovating the energy supply to make the remelting of light metal even more environmentally friendly. “We aim to become the greenest aluminum recycling plant in Europe,” explained Lützerath.
Trimet relies on renewable energy sources. Prior to the expansion, solar cells installed on the roofs of the production and storage halls cover a 3,000 sq m area, providing green electricity that already meets a large part of the plant’s own needs.
Now, the plant obtains the rest of its energy requirements from the waste heat of the melting furnaces. This makes the recycling plant fully self-sufficient in terms of electricity supply. A heat exchanger and two power plants convert the waste heat into electrical energy using Organic Rankine Cycle (ORC) technology. The self-generated electricity powers the processing plants, among other things. It also provides fuel for the company’s internal fleet, with all of the plant’s forklifts being converted to electric drive. In addition, TRIMET will feed approximately 20 GWh of waste heat into the public district heating network of Gelsenkirchen in the future. The conversion of waste heat into electricity reduces indirect CO2 emissions (so-called Scope-2 emissions) at the recycling plant by up to 100%. Direct emissions will also decrease significantly.
From autumn 2024, the recycling plant at Gelsenkirchen’s city harbor will operate the melting furnaces with hydrogen-rich energy gas obtained from Uniper Energy Sales via existing gas pipelines from the ArcelorMittal coking plant in nearby Bottrop, Germany. The coking plant gas contains more than 60% hydrogen and emits significantly fewer CO2 emissions as a fuel compared to fossil natural gas. This will save approximately 4,000 tons of CO2 annually at the Gelsenkirchen site, which is about a quarter of the currently generated carbon dioxide emissions. Moreover, there is the possibility of fully converting the operation of the recycling plant to hydrogen when it becomes economically available.