Products and solutions, 2010-11-16, 03:00 PM
450 fewer tons of particulate matter per year: ThyssenKrupp Steel Europe builds a further dedusting system
ThyssenKrupp Steel Europe has begun a further multi-million-euro investment project that will significantly reduce particulate matter emissions in Duisburg. The company is building an additional filter to capture sinter plant dust. The foundations have already been completed and building work on the steel frame for the 32 meter tall building has begun. The system will reduce particulate emissions by 450 tons per year. ThyssenKrupp Steel is investing 30 million euros in the project. Completion is scheduled for October 2011.
A sinter plant converts iron ore fines into a coarse-grained sinter suitable for charging in the blast furnace. The investment is part of a comprehensive filter system for the sinter belts. Exhaust air arising directly at the belts is extracted and today is cleaned by high-voltage electrostatic precipitators. The system cleans around a hundred billion cubic meters of gas a year. In the new system under construction, cleaned air is additionally passed through a fabric filter, which reduces the particulate matter content per cubic meter exhaust air by another more than 50 percent.
Only recently ThyssenKrupp Steel Europe installed state-of-the-art control technology to significantly improve the efficiency of older high-voltage electrostatic precipitators used to remove dust from the air inside the plant. As a further source of dust the mixing drums, in which the charge materials are mixed uniformly together, are now also being connected to the dedusting system. For the direct neighbors of ThyssenKrupp Steel in the north of Duisburg the systematic expansion of the sinter belt dedusting system will mean a major improvement in air quality. The company expects a reduction in particulate matter of around three micrograms per cubic meter air.
The new filter system is being built on a roughly 650 square meter site directly next to the sinter belts. The fabric filter has a surface area of around 13,640 square meters. It consists of almost 14,000 tubes through which the exhaust air is sucked. The dust collects on the walls of the tubes. The fan that sucks the air through the system at a speed of up to 22 meters per second is powered by a 1,800 kilowatt motor.
Reducing dust emissions has always been an important issue for ThyssenKrupp Steel Europe, not just since the decision to build the new filter system. Under a voluntary particulate reduction program the company has introduced a total of 41 measures to cut particulate pollution in recent years.
For instance, a dedusting system for the casthouse and stockhouse of blast furnace 1 was put into operation in October 2004. The 16.5 million euro system cleans 1.8 million cubic meters of air per hour via 18 different extraction points. Blast furnace 8, commissioned in December 2007, is equipped with a unique dust collection system for capturing emissions during rail car unloading. This system alone cost the company 20 million euros. Altogether, a quarter of the 250 million euro investment in the blast furnace was spent on pollution control. Together with the North Rhine-Westphalia environmental agency it has been proven that the new blast furnace produces virtually no diffuse dust emissions.