Cleaner than city air
Why would a steel producer need more than 44,000 extremely fine filter bags, each almost three meters long and with a total fabric area of 45,000 square meters? To filter out almost 100 percent of the dust generated during the production of sinter and thus improve the environmental situation in Duisburg. From commodity to high-tech: Sinter is used in the production of all steel products. The new fabric filter at thyssenkrupp Steel Europe is not only the biggest in the world, it is also the most efficient, capturing even the finest particulates. Its construction was a project of superlatives.
Carsten Rokitt: Client for the construction of the fabric filter and head of burden preparation at thyssenkrupp Steel Europe AG
He’s not easily impressed: After all, processing enormous volumes of raw materials is part of his daily work. But looking at the gigantic pipe sections for the stack – almost too big to be transported by ship – and the vast amounts of filters, cables and motors used in the fabric filter, even Carsten Rokitt was lost for words – almost. Watch this video to see what Rokitt, who is head of burden preparation, has to say about the fabric filter and environmental protection.
Modern electrostatic precipitators are already very good at filtering out sinter dust. But thyssenkrupp set itself the goal of going beyond official requirements and setting a new standard for reducing air pollution. The new fabric filter achieves this using tens of thousands of fine fabric bags which capture even very fine dust. Unbelievably, the air that comes out at the end of the process is cleaner than the air most of us breathe every day in big cities.
The waste air from the sinter plant is first cleaned by electrostatic precipitators that capture the greater part of the dust. But that still leaves a much bigger challenge: tiny dust particulates. To remove them, the waste air is fed through 44,000 extremely fine filter bags, each almost three meters long. The total fabric area of over 45,000 square meters is enough to clean up to 1.3 million cubic meters of waste air an hour, removing the residual dust almost entirely.
Steel is made from various raw materials, mainly iron ore and coke. The sinter plant is one of the first steps in steel production. Here, iron ore fines are mixed with coke and other materials such as lime, heated to a temperature of 1,200 degrees and baked together. The resultant “sinter cake” is then broken into lumps and cooled, ready for the next step in the steel production process: the blast furnace. To make the sinter cake requires hot air, which after the process is laden with dust. Conventional electrostatic precipitators collect most of this dust, but now thyssenkrupp’s new fabric filter, the biggest of its kind in the world, captures even the tiniest dust particles.
Dr. Wolfgang Volkhausen: Head of emissions control at thyssenkrupp Steel Europe AG
For Dr. Wolfgang Volkhausen, protecting the environment does not stop at the steel mill gate. The team leader for emissions control at thyssenkrupp is responsible for ensuring that official air pollution limits are met. Dr. Volkhausen is also member of a European community in which environmental experts such as him can swap ideas and experiences. As a result, thyssenkrupp operates one of the world’s cleanest iron and steel mills on its almost 10 square kilometer site in the north of Duisburg. The expertise of our environmental experts is in demand worldwide.
thyssenkrupp Steel Europe AG
Mark Stagge
Head of Public & Media Relations
