ThyssenKrupp Steel Europe Improves Environmental Performance with Dortmund CAL Upgrade
05/28/2012 - ThyssenKrupp Steel Europe AG has modernized the continuous annealing line at its Dortmund site. The new burner technology was developed specifically for use in the Dortmund CAL, and the investment of around 30 million euros will help reduce by half the nitrogen oxide emissions from the line.
ThyssenKrupp Steel Europe AG has modernized the continuous annealing line at its Dortmund site. The new burner technology was developed specifically for use in the Dortmund CAL, and the investment of around 30 million euros will help reduce by half the nitrogen oxide emissions from the line.
The Dortmund continuous annealing line processes steel from the coupled pickling-tandem cold rolling mill at the site and supplies it to the two electrolytic galvanizing lines on the site of the former Westfalenhütte mill. Built between 1984 and 1986, the line has a capacity of 60,000 tonnes per month. Among other grades, it processes bake-hardened and advanced high-strength steels for the auto industry.
The steel is annealed in eight heating zones, each fitted with 40 to 60 burners supplying the required temperatures. The burners work in a similar way to heating pipes: An air-gas mix burns inside them, heating the ambient air in the heating zones. Udo Zocher, responsible for the modernization project at ThyssenKrupp Steel Europe, said, “We have replaced the heating equipment with new state-of-the-art burners.”
Thanks to the new technology, the air-gas mix burns with practically no residues, according to ThyssenKrupp Steel Europe. In addition, the burners can be switched on and off individually as required, for energy optimization. A new control and automation system is said to ensure extreme precision in the annealing process.
A further environmental benefit, according to the company, is that the burners also work with the coke oven gas that ThyssenKrupp Steel recycles as an energy source for the continuous annealing line. The gas comes part-cleaned from the Prosper coke plant in Bottrop, where it is generated during the production of coke from coal. If there were no user for it, the coke oven gas would have to be flared off.