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One possible route for ironmaking process is using a hydrogen‐gas‐based fluidized bed to produce direct reduced iron (DRI), which allows to use the natural magnetite directly in particle scale. The magnetite particles are oxidized during the preheating stage before being charged into the reduction unit. The exothermic effect, the crystal transformation, and the structural evolution during the oxidation of magnetite are introduced. The oxidation of magnetite is summarized in both thermodynamics and kinetics aspects. Furthermore, the influence of the oxidation of magnetite on its subsequent reduction behavior is examined.

The EU commission has committed to fulfil the targets of greenhouse gas (GHG) emission reduction in 2050 by 80% in comparison to the level of 1990. The fulfilment of the EU's climate policies brings new challenges for the iron and steel industry. The European steel industry is forced to develop strategies for the transition of their technology to a carbon lean production and to keep the competitiveness in the world market. The steel companies in EU27 are taking the challenge to secure the steel production in Europe and have launched innovation projects for CO2 mitigation with the focus on the technological pathways Carbon Direct Avoidance (CDA) and Smart Carbon Usage (SCU), which are, beside Circular economy, defined as important pillars for CO2 abatement in European steel industry. The transformation of the steel industry must go hand in hand with a decarbonisation of the energy supply and other industries within EU27.

The increase in Basic Oxygen Furnace (BOF) plants in steelmaking has given rise to renewed interest in a dynamic simulation of the BOF process. Material and process costs can be saved with optimized process times and targeted charging of scrap and slag formers. Beside hot metal, scrap is the main source of iron in the BOF process. Furthermore, scrap is used as a coolant during the process due to exothermal chemical reactions occurring in the BOF. In this paper, the melting and dissolution behaviour of scrap in the BOF process is discussed. A new dynamic thermodynamic and kinetic Matlab ® model used to simulate scrap melting behaviour as a function of various scrap surface parameters and particle size is presented, as well as the influence of scrap properties on liquid bath temperature and final crude steel composition after a defined blowing period.

Since the beginning of BOF process, slag formation has been subjected to extensive development. During the initial stages of the blow, fast slag formation is primordial for the process performance. This is mainly to allow oxidizing reactions, and also to protect the refractory. A modeling of BOF process for the purpose of process optimization requires precise knowledge concerning the dissolution of CaO and MgO based materials. Using this knowledge, the optimal process conditions can be ensured by a controlling of the slag formation during the converter steelmaking process. Taking into account an application of large amount of different raw materials, as well as location-specific process conditions, the characterization of the dissolution behavior of different additives is an important key to improve the technological process. Thereby, in the frames of this project, an appropriate model for slag formation is established and compared to operational results for a 330t BOF, operating at ThyssenKrupp CSA, Santa Cruz, Brazil.