Production of Negative-Emissions Steel Using a Reducing Gas Derived from DFB Gasification

Abstract

A dual fluidized bed (DFB) gasification process is proposed to produce sustainable reducing gas for the direct reduction (DR) of iron ore. This novel steelmaking route is compared with the established process for DR, which is based on natural gas, and with the emerging DR technology using electrolysis-generated hydrogen as the reducing gas. The DFB-DR route is found to produce reducing gas that meets the requirement of the DR reactor, based on existing MIDREX plants, and which is produced with an energetic efficiency comparable with the natural gas route. The DFB-DR path is the only route considered that allows negative CO2 emissions, enabling a 145% decrease in emissions relative to the traditional blast furnace–basic oxygen furnace (BF–BOF) route. A reducing gas cost between 45–60 EUR/MWh is obtained, which makes it competitive with the hydrogen route, but not the natural gas route. The cost estimation for liquid steel production shows that, in Sweden, the DFB-DR route cannot compete with the natural gas and BF–BOF routes without a cost associated with carbon emissions and a revenue attributed to negative emissions. When the cost and revenue are set as equal, the DFB-DR route becomes the most competitive for a carbon price >60 EUR/tCO2.

Harmonized comparison of virgin steel production using biomass with carbon capture and storage for negative emissions

“…The variations in CO 2eq emissions from all sources are normally attributed to changes in system boundaries, CO 2eq intensities, and types of raw materials and energy. In this study CO 2 is captured from the flue gases of the entire plant and steam generation unit, except for grid electricity, whereas in other studies, only iron-making furnaces or all flue gases without on-site steam and/or power plant are included (Tanzer et al, 2020;Kuramochi et al, 2012;Stel et al, 2013;Fan and Friedmann, 2021;Pissot et al, 2021). Therefore, the results shown here are consistently at the lower end of the CO 2eq emissions compared to the literature data.…”

“…However, the CO 2 reduction potential of the DRI-EAF process compared with that of the BF-BOF reference case is limited to 48%. Applying CO 2 capture using MDEA/Pz (Tanzer et al, 2020), orange diamonds represent data from other literature resources (Hooey et al, 2013;Kuramochi et al, 2012;Stel et al, 2013;Fan and Friedmann, 2021;Pissot et al, 2021) (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.). Bui et al, 2018), for Biomass-BF-BOF: (Pinto et al, 2018).…”

“…Yang et al of only 47%. Pissot et al (2021) integrated biomass based dual fluidized bed gasification technology with DRI-EAF and CCS, which decreases CO 2eq emissions by 145% compared to BF-BOF. Fan and Friedmann (2021) provided an techno-economic assessment of BECCS application in BF-BOF and DRI-EAF combined with a carbon neutral electricity.…”

“…Fig. 52.Comparison results of CO 2eq emissions from literature resources and this study (green triangles represent calculation results in this study, blue dots represent data from(Tanzer et al, 2020), orange diamonds represent data from other literature resources(Hooey et al, 2013;Kuramochi et al, 2012;Stel et al, 2013;Fan and Friedmann, 2021;Pissot et al, 2021) (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article. ).…”

Catalysts and Batteries Recycling to Produce Ferroalloys and High‐Speed Steel

“…Many steelmakers have already developed alternative production routes with low or carbon-free technology. A non-exhaustive list includes the use of hydrogen, [3][4][5] direct reduction with a new gas source, [2,6] electrolysis, [5,7] and capturing the CO 2 . [5,8] Therefore, the environmental impact depends mainly on the electricity production technology from the coal power plant to hydroelectricity, solar panels, wind power, or nuclear plants.…”