New Trends in the Application of Carbon-Bearing Materials in Blast Furnace Iron-Making

Abstract

The iron and steel industry is still dependent on fossil coking coal. About 70% of the total steel production relies directly on fossil coal and coke inputs. Therefore, steel production contributes by ~7% of the global CO2 emission. The reduction of CO2 emission has been given highest priority by the iron- and steel-making sector due to the commitment of governments to mitigate CO2 emission according to Kyoto protocol. Utilization of auxiliary carbonaceous materials in the blast furnace and other iron-making technologies is one of the most efficient options to reduce the coke consumption and, consequently, the CO2 emission. The present review gives an insight of the trends in the applications of auxiliary carbon-bearing material in iron-making processes. Partial substitution of top charged coke by nut coke, lump charcoal, or carbon composite agglomerates were found to not only decrease the dependency on virgin fossil carbon, but also improve the blast furnace performance and increase the productivity. Partial or complete substitution of pulverized coal by waste plastics or renewable carbon-bearing materials like waste plastics or biomass help in mitigating the CO2 emission due to its high H2 content compared to fossil carbon. Injecting such reactive materials results in improved combustion and reduced coke consumption. Moreover, utilization of integrated steel plant fines and gases becomes necessary to achieve profitability to steel mill operation from both economic and environmental aspects. Recycling of such results in recovering the valuable components and thereby decrease the energy consumption and the need of landfills at the steel plants as well as reduce the consumption of virgin materials and reduce CO2 emission. On the other hand, developed technologies for iron-making rather than blast furnace opens a window and provide a good opportunity to utilize auxiliary carbon-bearing materials that are difficult to utilize in conventional blast furnace iron-making.

Pyrometallurgical removal of zinc from basic oxygen steelmaking dust – A review of best available technology

“…Solid based reduction processes are much more effective in the processing of zincbearing by-products. Common reductant sources include coke breeze, pulverized coal, and carbon-bearing revert material such as blast furnace dust (Ahmed 2018). Table 3 compares gas direct reduction and solid fuel direct reduction to conventional blast furnace pig iron production.…”

Modern blast furnace ironmaking technology: potentials to meet the demand of high hot metal production and lower energy consumption

“…Such composites are very attractive to the aspects of energy saving and environmental protection. The studies carried out on iron ore-carbon composite have demonstrated higher reduction rate and lower coke consumption compared to the ordinary burden materials [47][48][49][50][51][52]. It was demonstrated that the starting temperature of carbon solution-loss reaction (Boudouard reaction) decreased as the degree of contact between iron ore and carbonaceous material increased [52,53].…”

Non-Isothermal Reduction Kinetics of Iron Ore Fines with Carbon-Bearing Materials

“…The steel demand is anticipated to reach 1.5 times more than the present levels by 2050 to meet the demands of an increasing population [2]. Approximately 70% of crude steel depends on fossil fuel, such as coke [3]. The amount of CO 2 emitted by steelmaking factories was around 2.3 billion tons in 2007, while it is predicted to reach about 3.0 billion tons by 2050 [4].…”