R+D+I
SADIM has made an important effort researching the recycling of siderurgical wastes. This has led to make the next research projects.
Characterization and recycling of blast furnace sludges
This project was carried out with the University of Oviedo and it was focused on the recovery of blast furnace sludges (BFS) by using hydrocyclones. The aim of project was separate the fine fraction of the BFS, where the content of Zn is higher than in the coarse fraction, in order to recycle this coarse fraction into the steel process through the sinter plant. In the sinter plant the content of Zn in the raw materials must be controlled to avoid operation problems in the blast furnace.
In this way, a project of membrane filters was carried out as well, in order to dewater BFS to use them in the cement industry as iron bearing raw material.
Study of recycling iron bearing wastes
This study was carried out with ITMA (Instituto de Materiales de Asturias) and in it a briquette made of siderurgical residues was developed in order to use as mineral charge in the blast furnace. This agglomerate satisfied the stringent characteristics of the raw materials that are usually fed into the blast furnace as iron oxide charge. In the blast furnace the charge must have mechanical resistance and an adequate behaviour under reduction conditions to avoid collapsing the charge inside the furnace.
Pyrometallurgical processing of integrated steelwork wastes
This study was done in order to assess the viability of a process of making a self-reducing briquettes made of different iron bearing wastes from an integrated steelworks that can not be recycled due to their high ZnO content. This study was developed at the University of Oviedo with the aim of obtaining two products: iron sponge and zinc oxide. The iron sponge could be used as scrap charge in the basic oxygen furnace and the ZnO be sold to Zn production industry as raw material. The results were promising.
Recycling of carbonaceous steel mill wastes
Project developed with INCAR (Instituto Nacional del Carbón) with the aim of obtaining a briquette made of coal fines, residual oils and tar to be used as charge in the coke oven plant. In this study different blends of these residues were tested in order to get a briquette that could be used as raw material in the coke production. The results were promising and an industrial trial in a coke oven plant is going to be performed.
Inerting the steelworks slag by adding Al residues
Study of stabilization of steelmaking slag, adding mixtures of Al waste, so that it can be used in the construction of civil works, where such slag cannot normally be used due to its high rate of swelling.
Removing the Zn from the sludge in the Blast Furnace and steel plants in cast iron torpedoes
Study of the removal of the Zn from the sludge with high content of it, by agglomerating the sludge and adding cast iron in the torpedoes in order to capture the Zn and incorporate the metal part of the sludge into the cast iron.
Use of waste from aluminium cans and metal shavings as raw material
Study and project consisting of treating and agglomerating waste from aluminium cans and metal shavings in order to use them as an additive in steelworks.