The article presents results of the research on the use of chars produced during pyrolysis of residual biomass as a substitutional fuel in the iron ore sintering process. Such an approach allows to implement circular economy and industrial symbiosis to the iron and steel branches. The effect of the substitution of conventional coke breeze fuel used in sintering on final sinter quality and emission was examined. With regard to productivity, fuel consumption, and properties of the sinter it was shown that the share of tested biochars in fuel may be kept at 10, and up to 30 wt.%, depending on the biochar type. It was observed that with the use of the biochars, the content of iron oxide in the sinter decreased, which was advantageous. Moreover, the sinter obtained in the presence of biochars was characterized with better strength and abrasion than the sinter obtained with coke breeze-based fuel, improving the final product quality. The presence of biochar influenced the raw exhaust gas composition and resulted in a slight increase of organic and inorganic carbon compounds content, while the amount of sulfur oxides was noticeably decreased. It was concluded that the biochars may be applied in the sintering process at established share in the fuel stream.

Metallurgical wastes landfills in Poland significantly grew during last four decades. Landfilled wastes are characterised by iron content at range 30–50% and zinc content about 2–3%. Therefore wastes are not interesting for the zinc smelter, on the other hand, even such low zinc content in ironmaking burden causes problem with a shaft furnace operation. So, the wastes are valuable for ironmaking due to the high iron content, provided that zinc will be removed from them. The article describes the general ways of dealing with zinc containing metallurgical wastes. In detail, the semi-industrial research conducted on sinter pot set of Stanislaw Staszic Institute for Ferrous Metallurgy is presented. The study determined the conditions under which obtained three benefits: landfilled sludge utilisation, raw materials substitution and zinc recovery.

The article was prepared on the basis of reports from the Green Steel for Europe (GREENSTEEL) project funded by the European Union as part of the implementation of the climate and energy goals for 2030 and the long-term strategy for a climate neutral Europe by 2050. A consortium of implementers composed of ten partners from EU countries, including Łukasiewicz – Institute for Ferrous Metallurgy in Gliwice, has identified promising technologies for the decarbonisation of the steel industry, defined technological pathways constituting process chains composed of these technologies, as well as scenarios of the decarbonisation process until 2030 and until 2050. The end result of the project is a set of insights and recommendations for effective clean steel manufacturing solutions suitable for the EU to achieve the EU’s climate and energy goals.

The metallurgical industry is seeking raw material substitutes more and more intensively in order to replace materials traditionally used in pig iron production. Research has been conducted on the use of char obtained from waste car tires via a pyrolysis process in an iron ore sintering process. The char obtained from car tires could be a potential substitute for some of the coke breeze used in the iron ore sintering process. However, the Zn and S content of the char is a major technological issue. This paper presents the results of research conducted to assess the possibility of substituting coke breeze with a commercial char from waste tires. The experiments were carried out in a laboratory stand capable of sintering 200 kg of sintering blend. The results obtained show that it is possible to replace 10 %m/m of coke breeze with waste tire char without any technological danger for sintering lines. The application of waste tire char in metallurgical processes is an example of actions that form part of the circular economy and also of the appropriate use of anthropogenic resources that are technologically available.

The article presents some aspects of the current trends in changes in the state of steel smelting technology in the world, which are an attempt to respond to the serious destabilization of climatic and environmental conditions in the world as a result of excessive global emissions of carbon dioxide, including by the iron and steel industry. Since the concept of sustainable development refers to the entire closed cycle of iron and steel production along with development prospects, the article consists of three chapters: I. Problems and methods of managing iron-bearing waste in iron and steel industry. II. Transformation of the traditional blast furnace – basic oxygen furnace steel smelting technology to low CO ₂ emission technologies. III. Net zero CO ₂ emissions (fossil-free) steelmaking technologies. Chapter I emphasizes that in the sustainable development of all technologies, the effective and environmentally harmless transformation of waste materials should be the priority throughout the entire steel technological and production chain. Chapter II refers to the necessary modernization projects in the current dominant two-stage technology for producing iron and steel: a blast furnace - a basic oxygen furnace. This technology is the main emitter of carbon dioxide in the iron and steel industry, including the production of blast coke. The gradual elimination of this method of steel production means that in the transitional period there will be a need to adapt existing blast furnace installations to the DRI process for producing metalized pellets. The problems of developing low-emission technologies for producing iron and steel are the subject of many projects conducted by many industry and university research centers. Chapter III mainly concerns the development of research on prospective zero-emission steel production technologies using hydrogen as an iron oxide reducer. The importance of this type of technological solutions for radically reducing CO ₂ emissions in the iron and steel industry seems to be decisive in the chain of modernization and transformation efforts, as well as research on new technologies in the iron and steel industry, which have been undertaken for many years.