Trimet Aluminium SE has commissioned a new anode baking furnace at its aluminium smelter in Hamburg, Germany.
The new anode baking furnace with 48 chambers replaces an eight-year-old furnace and substantially improves energy efficiency. Contributing to that is a modern firing system whose gas burners make more efficient use of energy while simultaneously producing less emissions. In addition, the material is optimized: the bricks used for the furnace walls are easier to heat up, so that considerably less energy is needed.
“With the new baking furnace, we will produce even more energy-efficiently in the future. This means that the investment in modern technology is paying off twice for Trimet. We are optimizing the quality and performance of our production while also ensuring that our processes are more sustainable,” says Andreas Lützerath, member of Trimet’s executive board. Around twelve million euros were invested for the new plant.
Carbon anodes are needed for the production of primary aluminium. In fused-salt electrolysis, liquid aluminium is produced from the chemical reaction of the input material (alumina) with carbon using electrical energy. The anodes assume the functions of both current conductor and reactant in this process.
Construction of the anode baking furnace a “technical and logistical challenge”
The Trimet site in Hamburg produces anodes for its own metal production and also for the Trimet smelter in Essen. Around 120,000 tonnes of carbon anodes are baked annually in the anode plant. For this, petroleum coke mixed with coal tar pitch are converted to a conductive substance by the thermal baking process in the furnace. The anode bodies, 1.60 m in length and weighing almost 1.2 tonnes, are gradually heated up to 1,100 °C in the firing chambers in a process that lasts 18 days, and then cooled again.
“The new construction of an anode baking furnace during ongoing operation was a technical and logistical challenge that the team mastered with flying colours in record time. We can all be proud of the smooth outcome of the project in just ten weeks. Now we can fully concentrate on production again,” says Jörg Prepeneit, Trimet plant manager in Hamburg.
Meticulous planning was an important factor because the engineers and more than 100 bricklayers had to coordinate their with the on-going firing process. For the new baking furnace, from 34 different types of bricks a total of 9,000 tonnes or more than 1.5 million bricks were laid. Many of those bricks were individually manufactured and fitted into their specific positions.
The Trimet plant in Hamburg employs around 380 people. They produce about 130,000 t of primary aluminium and 120,000 t of carbon anodes annually.