Influence of drying temperature and atmosphere on the mechanical strength of iron‐ore agglomerates and sodium silicates for application in sintering processes

Abstract

This paper presents the influence of drying temperature and atmosphere on the mechanical strength of iron-ore agglomerates and sodium silicates. Mixtures of different pellet feed and sodium silicates were produced with a ball disc and cured at various temperatures. The resulting products exhibited sufficiently high mechanical strength to be transported over long distances and handled until their use in sintering processes. The agglomerates were dried/cured at temperatures between 100-550 8C and in gaseous atmospheres consisting of air and/or carbon dioxide. During this process, a strong influence of both temperature and atmosphere on the compression strength after contact with water, as well as on the morphology of the sodium silicates, was observed. The use of carbon dioxide atmosphere during drying proved effective for achieving high mechanical strength after water immersion. A phenomenological approach was developed to explain the results in order to connect morphology and mechanical properties.

Production of solid biofuel granules from drum granulation of bio-waste with silicate-based binders

“…It was reported that the drying temperature of agglomerates had an important influence on the consolidation of sodium silicate. The dehydration of sodium silicate binder in less than 550  C did not provide total insolubility of the sodium silicate in water [18,34]. Therefore, the difference between the initial and the post compressive strength of the granules might be caused by the structure weakening of sodium silicate during the water immersion experiment, which was further confirmed by the difference of Si content in the solution after water immersion experiments for different granules (Table S2).…”

“…This water resistance offers significant advantages over water soluble binders used in other studies particularly when considering deployment of the technology in wetter climates. Such inorganic binders have been used successfully to consolidate fines or small particles into larger 6 units in the processes of agglomerating bentonite, detergent, iron ore, silica and coal [18,19,20]. In this study, we have investigated the possibility of using an inorganic silicatebased binder in a drum granulation process for the production of bio-waste granules using compost as the model bio-waste.…”

Obtaining Granules from Waste Tannery Shavings and Mineral Additives by Wet Pulp Granulation

“…Soluble sodium silicate binders (water glass) have been widely used in industries due to their low cost, odorless nature, and non-toxicity. They also offer a higher level of binding performance such as strength, durability, and water resistance [ 44 ]. In a further study [ 45 ], the authors investigated the possibility of using a sodium silicate solution in a drum granulation process for the production of bio-waste granules.…”