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The article assesses the future role of hydrogen‐based iron and steel making and its potential impact on global material flows, based on a combination of technology assessment, material flow analysis, and microeconomic analysis. Renewable hydrogen‐based iron production can become the least‐cost supply option at a carbon dioxide (CO2) price of around United States dollars (USD) 67 per tonne. Availability of low‐cost renewable electricity is a precondition. Australia is the world's largest producer of iron ore and at the same time a country with significant low‐cost renewable electricity potential. A shift to direct reduced iron (DRI) exports could reduce global CO2 emissions substantially and at the same time increase value added in Australia, while maintaining steel production in countries that are currently processing ore into iron and steel, such as China, South Korea, and Japan. The approach could be expanded to other parts of the world and other energy‐intensive industry sectors. Such relocation analysis in a climate context can become a new industrial ecology research area. Iron and steel industry CO2 emissions can be reduced by nearly a third, around 0.7 gigatonnes (Gt) CO2 per year. To achieve these emission reductions, investment of USD 0.9 trillion, or 0.7% of the total energy sector investment needs, would be required, global DRI production would have to increase seven‐fold from today's level, and the hydrogen energy used would equal 1% of global primary energy supply. Such a shift could develop from 2025 onward at scale, if the right policies are put in place. [ABSTRACT FROM AUTHOR]

Abstract: Ferroalloys are defined as iron-bearing alloys with a high proportion of one or more other elements – manganese, chromium, silicon, molybdenum, etc., mainly used by the iron and steel industries. Life cycle assessment methodology was used to estimate the greenhouse gas (GHG) footprint of a number of these ferroalloy production processes. The results of the study showed that GHG footprint for ferroalloy production in Australia was 1.8 t CO2e/t FeMn, 2.8 t CO2e/t SiMn and 3.4 t CO2e/t FeSi alloy metal. These results compare with GHG footprints for ferronickel and ferrochromium of 13.9 t CO2e/t and 3.0 t CO2e/t, respectively revised from an earlier study. These GHG footprint estimates were calculated using the Tasmanian electricity greenhouse gas emission factor since these ferroalloy industries are located in Tasmania, Australia. The major difference in greenhouse gas emissions between the various ferroalloys is largely due to their respective amounts of electricity use and coke/coal consumption. These results are not too different to the results from a limited number of studies reported in the literature when compared on a similar electricity source basis. The LCA results also showed that coke and coal usage contributed close to 60% or more of the total GHG emissions from the various ferroalloy production processes. In light of this finding, there would appear to be an opportunity to reduce GHG emissions from ferroalloy production if fossil fuel-based coal is replaced with biomass based renewable carbon. [Copyright &y& Elsevier]

This article reports that the presence of phosphorus sharply reduces the commercial value of ferroalloys made from the ores. The contents of iron, silicon, and phosphorus impurities in manganese ores are limiting factors in the beneficiation process, but phosphorus is especially important in this regard. The problem of preparing low-grade manganese ores for smelting does not even exist in most foreign countries, since metallurgical plants in those nations tend to use high-quality ores imported mainly from Africa, South America, or Australia. Physicochemical methods of ore beneficiation that are used to prepare phosphorus-bearing ores for smelting do not separate phosphorus from manganese, since phosphorus is usually present in ore minerals in the form of a finely dispersed mechanical impurity. When part of the phosphorus is present in the form of free phosphates, it is sometimes possible to reduce its content in the commercial concentrate. However, it is not cost-effective to remove all of the phosphorus.