Comparison of Compressive Strength of Fly Ash Bonded Flue Dust Briquettes with that of Briquettes made with Bentonite, Sodium Silicate, Lime, Starch, Pitch, Molasses and Dextrin Binder

Blast furnace flue dust and thermal plant generated fly ash are major solid wastes coming from the two important industrial sectors. Flue dust mainly contains iron oxide and carbon. The fly ash contains mostly silica, alumina and iron oxide with small amount of lime. These materials are commonly used in making of bricks and tiles. Little amount of flue dust is used in charge material preparation for iron extraction. In this present study, fixed quantities of blast furnace flue dust (30 wt %) and pure iron oxide fines (65 wt %) are mixed with different binders such as bentonite, lime, sodium silicate, fly ash, starch, molasses, pitch and dextrin. The strength of composite briquettes was determined at green, dry and cured conditions. Moreover, the effect of the variation of fly ash quantity, fly ash particle size, briquetting pressure and curing temperature on the compressive strength of composite briquettes were also investigated. The optimized fly ash quantity of 5 wt%, fly ash particle size of 75 mu m (200 mesh), briquetting pressure of 95 MPa and curing temperature of 300 & DEG;C provide maximum strength to the briquettes. The phase analysis through XRD and morphology analysis through FESEM-EDS of fly ash added cured composite briquettes were performed.

Automated summary

This study focuses on the preparation of composite briquettes using blast furnace flue dust and pure iron oxide fines mixed with different binders. The effect of fly ash quantity, particle size, briquetting pressure, and curing temperature on the strength of the briquettes was also investigated.