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).

   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.