The work done in this study was devoted to the development of a procedure to produce brick from water
treatment plant sludge and silica fume as a modern way for sludge reuse. Disposing the sludge to the nearest
watercourse is the common practice all over the world, which accumulatively rise the aluminum concentrations in
water and consequently in human bodies. This practice has been linked to occurrence of Alzheimer’s disease.
Landfill disposal of the sludge is impractical because of the high cost of transportation and it depletes the capacity of
the landfill. The use of sludge in construction industry is considered to be the most economic and environmentally
sound option. Due to the similar mineralogical composition of brick clay and water treatment plant sludge, this study
focused on the reuse of sludge incorporated with silica fume in brick making through the sintering process. The
study investigated the complete substitution of brick clay by water treatment plant sludge incorporated with silica
fume (SF). In this study, three different series of sludge to silica fume (SF) proportions were studied, which
exclusively involved the addition of sludge with ratios 25, 50, and 75% of the total weight of sludge-SF mixture.
Each brick series was fired at 900, 1000, 1100, and 1200 oC. The physical and mechanical properties of the
produced bricks were then determined and evaluated according to Egyptian Standard Specifications (E.S.S.) and
compared to control brick made entirely from clay. From the obtained results, it was concluded that by operating at
the temperature commonly practiced in the brick kiln, 50 % was the optimum sludge addition to produce brick from
sludge-SF mixture. The produced bricks properties were obviously superior to the 100 % clay control-brick and to
those available in the Egyptian market. |