Sustainable Utilization of Textile Dyeing Sludge and Coal Fly Ash by Brick Production Through Traditional Kilns

Abstract

The fundamental purpose of this study was to evaluate the technical feasibility of incorporating fly ash (FA) and dyeing sludge (DS) in the production of brick. An attempt was taken to replace 10% to 100% clay by DS and FA in brick-making by volume. A brick firing kiln was used to burn the uniform-shaped bricks after replacing clay with DS and FA. Size and shape, hardness, soundness, water absorption, efflorescence, dry density, loss of ignition, firing shrinkage, specific gravity, compressive strength, and leaching tests were carried out to study the properties of these bricks. The compressive strength of the brink ranged from 6.25 MPa to 0.33 MPa and indicates a decreasing pattern in strength with the increase in the volume of DS and FA. Only 18.8% water absorption capacity was found in control bricks without DS and FA, while a maximum absorption of 40.19% was found for a particular combination of DS and FA. Similarly, dry density decreased with the increase in the volume of DS and FA. Besides, efflorescence in bricks was found within the allowable limits for certain combinations of DS and FA, which exceeded the allowable limits for other combinations. The presence of heavy metals (Ni, Zn, Cr, Cu, and Pb) in the extraction solution was insignificant. Based on the results of this study, we recommend that up to 10% clay can be substituted with DS and FA without substantially affecting the quality of bricks.

Keywords

• dyeing sludge, coal fly ash, brick production, compressive strength leachability