Oschatz Power GmbH products

Tried-and-tested waste heat boilers for energy recovery and the use of heat from exhaust air from sinter coolers form a substantial part of the extensive Oschatz portfolio. These cool hot sintered material with ambient air. By means of the hood construction above the sinter cooler, the heated cooling air is collected and processed in a waste heat boiler to generate steam and/or hot water. The installation of an Oschatz waste heat boiler means that the significant heat being produced can be captured, saving large amounts of primary energy. Waste heat boilers for installation downstream of both sinter belts and sinter coolers with and without auxiliary firing and incorporating hot air recirculation from sinter coolers provide combustion air for auxiliary burners. If desired, it is also possible to raise the temperature level of the waste heat boiler through the installation of a gas burner. Superheated steam can then be produced for running a steam turbine.

An example for the Direct-reduction process systems is the Hlsarna process, which was developed as part of the ULCOS project (Ultra-Low Carbon Dioxide [CO2] Steelmaking). This has the goal of halving the carbon dioxide emissions in steel production. Oschatz built waste gas cooling sections in connection with the HIsmelt process for the first time in 2005; these have been successfully used in the HIsarna process since 2011. This forward-looking process combines the preheating and partial pyrolysis of the coal in the reactor, the melting cyclone for melting iron ore and the melting crucible for subsequent reduction of the iron ore and iron extraction. The consumption of coal is thus reduced, which results in a significant cut in carbon dioxide emissions. The round design conceived by Oschatz. provides a particular contribution to ensuring maximum efficiency in the production of steel.

Flash smelting of copper and nickel concentrates takes place in a furnace with reaction shaft (Outokumpu flash smelting process). The process gases are cooled in a special waste heat boiler. The products are traditionally processed further on in a converter. The horizontal waste heat boiler downstream of the Outokumpu flash smelting process consists of a radiation chamber in which the gas is cooled down to 600 °C – 800 °C and an adjacent convection part in which convection heating surfaces are installed. The waste heat boilers are equipped with membrane walls, bulkheads and bundle heating surfaces. To avoid corrosion in the waste heat boilers, the water/ steam-side operating pressure is typically set between 40 and 70 bar.

In the in-bath lance smelting technology, the brick-lined furnaces and hoods are typically surrounded by a water cooled jacket. Oschatz supplies a furnace and hood cooling system that is integrated into the evaporation system of the waste heat boiler. These components are designed as gas-tight welded membrane walls. In order to protect the membrane walls from excessive heat loads, they are fitted with studs onto which a thin castable layer is attached. The lifetime of these components complies with the usual average lifetime of boiler pressure components. In contrast, the brickwork of an originally water cooled construction needs to be relined at least once a year. The engineering concept developed by Oschatz leads to significantly less downtime, resulting in significantly increased production capacity and therefore assures that the whole plant is more economical.