2010 Volume 50 Issue 2 Pages 200-206
In this paper, the concept of grading of the feed ores has been used for the purpose of evaluation of the compactness of the briquettes. Fuller curve, the most popular ideal grading curve, has been considered. Ideal grading curves can lead to the maximum extent of compaction in the briquettes, ensuring highest strengths of the briquettes. The strength of the briquettes from a given fine ore mix has been assessed in relation to the extent of shift of the grading curve for the feed mix, from its ideal Fuller curve. Two parameters, namely, root mean square deviation (RMSD) and coefficient of uniformity (CU) have been used as the measure of the shifts from the corresponding Fuller curves. Mathematical equations have been derived to establish the correlations between the shatter strengths and hot compressive strengths with RMSD and CU. It is observed from the current work that closeness of a feed mix to its Fuller curve can provide satisfactory strength of the briquettes, but the incremental benefit in strength of the briquettes is reduced progressively with closeness to Fuller curve. This approach can be used to produce briquettes of significantly high strength through selective and optimised grading of the feed mixes.