Contherm process provides fuel for energy generation

Krupp VDM GmbH has supplied around 85 metric tons of its high temperature Nicrofer 3220 H - alloy 800 H to build two rotary kilns for waste treatment. These kilns will form the core of a so-called Contherm plant being built by Technip Germany GmbH for the Westfalen power station of VEW Energie AG in Hamm-Uentrop, Germany. The Contherm plant utilizes the chemical process of pyrolysis to recover fuels and reusable raw materials from waste products.

The plant processes scrap plastics, shredder residues (e.g. from scrap cars), industrial waste and household garbage. The waste products are heated in the rotary kilns to around 700°C. As this takes place in the absence of oxygen, the wastes do not burn but decompose. The products of this pyrolysis process are hot gas, coke, iron and nonferrous metals as well as stones and glass. The gas and coke will be used to fire generating unit C at the Westfalen power station, replacing up to ten percent of the coal generally used to fuel the 320 megawatt generating unit.

The rotary kilns are each 30 meters long and are heated from the outside by gas burners. The pyrolysis gases produced contain impurities such as sulfur dioxide and hydrogen chloride. Nicrofer 3220 H was selected as this austenitic alloy displays outstanding long-term heat resistance and strength at temperatures above 600°C. High nickel and chromium contents guarantee resistance to oxidation, thus protecting the rotary kilns from the impurities in the pyrolysis gas. Other typical applications for the material include ethylene pyrolysis furnaces and components for coal gasification plants and steam/hydrocarbon reformers.

For further reference: ThyssenKrupp AG, Trade Press, Bernd Overmaat
Tel: +49-211-824-36012, Fax: +49-211-824-36035
e-mail: overmaat@tk.thyssenkrupp.com