Electro- or Turbo-Driven?—Analysis of Different Blast Processes of Blast Furnace

There has always been a dispute about the energy efficiency and energy cost of electro-driven and turbo-driven blast furnace (BF) blast processes. In order to find where the problem lies, energy efficiency analysis models and energy cost analysis models of electro-driven and turbo-driven blast processes were established, and the differences between the two driving processes in terms of theoretical minimum steam consumption, energy efficiency and energy cost were studied. The results showed that the theoretical minimum steam consumption of a blast process depends on steam thermodynamic properties and is unrelated to drive mode and drive process. A certain overlapped interval between electro-driven and turbo-driven blast processes in terms of energy efficiency exists. The equation for calculating the standard coal coefficient of steam was proposed, and the relationship to judge strengths and weaknesses of the two driving modes in terms of energy efficiency and energy cost was established. Finally, two companies were selected for case study research. The results led to different conclusions because of the differences between energy media in terms of standard coal coefficient and unit price. To select the best driving mode, plant-running conditions and energy prices of the region of operation in addition to other relevant factors should all be taken into account.