Top Pressure Recovery Turbines

As most BFs are operated with high pressure blasts, the gases leaving the furnace at the top still maintain a pressure of up to 3 bars and have a temperature of around 200 oC.  This pressured gas can be used in a turbine – referred to as Top-pressure Recovery Turbine (TRT) – to generate electricity. TRTs can produce 15–40 kWh/t-HM and their output can meet around 30% of all electricity needs of all BF equipment, including air blowers (IEA, 2007. p.123). The gas leaving the TRT system can still be used as fuel in other iron and steel processes (Worrell, et al., 2010. p. 85)

TRT systems are categorized as wet and dry systems, depending on the method they use to remove the dust particles – which is necessary for proper turbine operation. Dy systems use less water and electricity, and typically produce 25 to 30% more power (APP, 2010. p.40) up to 60% more power generation possibility is noted in Worrell et al. (2010) – mainly because higher gas temperatures are retained. Dry systems are therefore regarded to have more favorable economics (EIA, 2007, p. 123).

Chinese flag Indian flag US flag This technology is regarded to have a high application potential for China, India and the United States, and in particular for the new plants, as the retrofitting of existing blast furnaces may not be easy.

Development Status Products

Top Pressure Recovery TurbinesCosts & Benefits

Parent Process: Blast Furnace System
Energy Savings Potential

40–60 kWh of electricity can be produced per ton of hot metal (APP, 2010. p.40)

A dry-types TRT installed at a 1 Mt/y BF produced 55.4 GWh/y of electricity (NEDO, 200. p. 74)

CO2 Emission Reduction Potential

If TRT were Installed Worldwide at all the Furnaces Working at Elevated Pressure, CO2 emissions can be reduced by 10 Mt/year.


For a 1 Mt/y blast furnace, the installation cost of a 7 MW dry type TRT was ¥400 million for equipment and ¥400 million for construction. The payback time for the whole investment was around 1.8 years. (NEDO, 2008. p. 74)

Top Pressure Recovery TurbinesSchematic

Top Pressure Recovery Turbines Publications

Global Warming Countermeasures: Japanese Technologies for Energy Savings / GHG Emissions Reduction

This revised 2008 version of the publication from New Energy and Industrial Technology Development of Japan includes information on innovative Japanese technologies for energy efficiency and for the reduction of COemissions.  

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The State–of-the-Art Clean Technologies (SOACT) for Steelmaking Handbook


The State–of-the-Art Clean Technologies (SOACT) for Steelmaking Handbook is developed as part of the Asia-Pacific Partnership on Clean Development and Climate program and seeks to catalog the best available technologies and practices to save energy and reduce environmental impacts in the steel industry. Its purpose is to share information about commercialized or emerging technologies and practices that are currently available to increase energy efficiency and environmental performance. 

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Energy Efficiency Improvement and Cost Saving Opportunities for the U.S. Iron and Steel Industry

The U.S. Environmental Protection Agency’s (EPA) energy guide, Energy Efficiency Improvement and Cost Saving Opportunities for the U.S. Iron and Steel Industry, discusses energy efficiency practices and technologies that can be implemented in iron and steel manufacturing plants. This guide provides current real world examples of iron and steel plants saving energy and reducing cost and carbon dioxide emissions.

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