Briquettes with Increased Reaction Surface Area

Abstract

In the reduction process of ores, agglomerates, pellets, and briquettes, besides the mineralogical structure, chemical composition, porosity, working temperature, and composition of the gas phase, the specific surface area of the reaction front (cm² surface area per briquette or cm³ briquette volume) also plays a particularly important role. Considering the stresses that briquettes are subjected to during handling, transport, and storage, the most suitable shapes are spherical or ovoid. However, these shapes have the disadvantage of low specific surface values for the reaction front during the reduction process. From the perspective of specific surface area (i.e., its value), cubic or parallelepiped-shaped briquettes would be more appropriate, but they suffer from greater degradation during handling. For waste materials with low reducibility, increasing the specific reaction surface can be achieved by briquetting ores or waste into multi-cavity or tubular briquettes with internal cavities, even though the briquetting installations become more complex from a structural and functional point of view compared to the simpler forms mentioned above. For waste materials with medium reducibility, tubular briquettes are considered a very good solution.