ATMOSPHERE AIR FURNACES NEWS

European manufacturer thyssenkrupp Steel Europe AG (tkSE) is revamping burner technology at their continuous galvanizing line located in Bochum, Germany. This modernization measure is an important cornerstone in enabling thyssenkrupp Steel to produce high-strength steels (AHSS) in Bochum in the highest quality and with increased production capacity for further use in the automotive industry.

In order to meet market requirements and reduce both emissions and energy consumption, Tenova LOI Thermprocess will ensure that the furnace will be equipped with new burners that meet even highest requirements by targeting the lowest possible NOx-emission levels (lower than 140 mg/Nm³ (@3%O2 reference)) during production. In addition, the heating system will be upgraded in order to increase the target strip temperatures to > 900°C.

This is the third consecutive modernization order that this sister company to North American engineering company, Tenova Inc., received for the continuous galvanizing line in Bochum.

With an annual production capacity of 540,000 t of high quality galvanized steel it is one of the core production lines of thyssenkrupp Steel Europe for the production of car body parts and AHSS-steels.

The line was commissioned in 1992, and since 2014  major parts have been upgraded with the latest technologies. In the first phase, the pre-heating and over-aging sections were modified to improve the annealing cycle in over-aging regarding larger heating capacity and improved temperature homogeneity. The energy recovery in the pre-heating section has nearly doubled and therefore the carbon footprint of the line was significantly reduced.

In 2017, a major step towards production of AHSS was realized through a substantial revamp of the fast cooling section. A new set of nozzle boxes, fans and heat exchangers were added to the existing equipment. The system is designed for highest heat transfer coefficients and lowest strip vibrations, even with enlarged strip length without roller support.

"The modernization step that is now pending is important in order to meet our customers' upcoming requirements for hot-dip galvanized materials," explained Dr. Carsten Groß, team leader of FBA7 at thyssenkrupp Steel. "We are also relying on Tenova LOI's experience and expertise in the field of burner technology for this project. The upgrade of our FBA7 is part of the modernization strategy at the Bochum site."

"Together with tkSE, we developed a well-defined modernization strategy with intense R&D effort in different steps," said Sascha Bothen, head of sales LOI Group. “This project proves that innovative revamping solutions can give an economic and technological benefit even for plants that have been in operation for a long time.”