Speaker
Description
The steelmaking industry plays an important role on the global anthropogenic $CO_2 $ emissions, accounting to 7 % of all global emissions. In addition, this industry also produces many by-products whose direct disposal without a proper treatment represents an environmental hazardous. In recent years, the recycling of these by-products is gaining increased relevance, to achieve a more environmentally friendly and sustainable steel production. Several processes have been deployed in the industry, with most of them, being based in pyrometallurgical methods, whose energy consumption, operational costs, and $CO_2$ emissions, hinder the wider usage of these technologies. To decrease these factors, microwave heating is being suggested as an alternative technological since it is more efficient and cleaner than the conventional counterpart.
The aim of this work is to give an insight on the operational parameters of a continuous recycling process of steelmaking by-products using microwave radiation as the heating source. A mathematical model was implemented using COMSOL Multiphysics. Firstly, this model was compared with a previously validated simplified model from the literature, to access both COMSOL Multiphysics capabilities and the phenomena happening in the process. Afterwards, the numerical model is modified for the process under consideration and several parametric studies are performed to determine their influence on the operational conditions. The results showed that, that a scaled-up size and thermal insulation are essential to the process global efficiency. From an emissions standpoint, it was proven that using lower C/O ratio mixtures can reduced the emissions. As for the flow current orientation, it was concluded that the usage of co-current flow might provide better temperature conditions, without hindering the power requirements.