Cold strength enhancement mechanism of carbon composite iron ore hot briquet

Abstract

Hot briquetting process was proposed as a new manufacturing method of carbon composite iron ore briquet. The process was a binder-less briquetting in use of thermal plasticity of coal. The briquet by hot briquetting was higher apparent density and lower porosity than a cold bonded briquet. In order to enhance a cold strength and an apparent density of the briquet, the briquet was made by a double roll type briquetting machine at various conditions. Effects of hot briquetting conditions and coal properties on the briquet properties were investigated and the cold strength was discussed relating to pore structure of the briquet. Porosity and crushing strength of the briquet changed with hot briquetting temperature. Crushing strength of the briquet had a maximum value at near temperature standing at maximum fluidity of coal measured by Gieseler plastometer. Increasing maximum fluidity as caking property of coal, crushing strength of the briquet increased with decreasing in the briquet porosity and increasing in coherence to coal and iron ore.