Siemens VAI supplies efficient, ecofriendly and complete solutions for iron and steel companies such as voestalpine Stahl GmbH of Linz, Austria. At its large-scale steelworks, voestalpine produces 2.8 million tons of sinter – a key source of iron for the blast furnace process – out of fine ores and charging materials. Since today’s tougher emission standards cannot be met with conventional technologies, the particular combination of environmentally harmful emissions generated in iron ore pretreatment is now the main challenge facing sinter offgas-cleaning systems.

A revolutionary concept, knowhow in waste-gas treatment, an iron will to innovate – the conditions for a successful launch in Linz couldn’t have been better. It’s no surprise then that the project was ready for implementation in 2003 – only a year after planning had begun. The underlying cutting-edge technologies dovetail perfectly:

Conventional sinter plants are under attack by environmental authorities worldwide due to the enormous amount of offgas they produce and the damage they cause to the environment,” explains Stefan Hötzinger. “That’s why it was vital for us to set radically new standards for emission reduction and environmental friendliness in our joint pilot project with voestalpine.” An eco-care analysis of MEROS conducted by the Siemens’ Corporate Technology Department in Europe and China has shown that seamlessly integrating the MEROS and SWGR processes reduces primary energy requirements as well as emissions. At the voestalpine plant, which produces 2.8 million tons of sinter a year, SWRG reduces annual coke consumption by 11,200 tons and/or annual natural gas consumption by 820,000 Nm³ – thereby cutting annual CO₂ emissions at the plant by 45,000 tons. At the same time, MEROS reduces fine particulate emissions by 138 tons, sulfur dioxide emissions by 1,200 tons, mercury emissions by 1,000 kilograms, dioxin/furan emissions by 30 grams and wastewater production by 125,000 m³.

“You can’t talk about complete success unless everyone benefits,” Hötzinger emphasized. “But this is precisely what we have here. First, we save our customers energy and operating costs of some €5 million a year. Second, the voestalpine plant is an important reference project that Siemens VAI Metals Technologies can now use as a door opener to the global market in other industries such as pulp and paper production and power generation. And third, the environment benefits from a 97–99 percent reduction in fine particulates, heavy metals and organic emissions like hydrocarbons, dioxins and furans – the last two of which pose major health hazards.”