The water sludge is generated from the treatment of water with alum. Disposing of sludge
again to the streams raises the concentrations of aluminum oxides in water, which has been linked to
Alzheimer’s disease. The use of water treatment plant (WTP) sludge in manufacturing of constructional
elements achieves both the economical and environmental benefits. Due to the similar mineralogical
composition of clay and WTP sludge, this study investigated the complete substitution of brick clay by
sludge incorporated with some of the agricultural and industrial wastes, such as rice husk ash (RHA) and
silica fume (SF). Three different series of sludge to SF to RHA proportions by weight were tried, which
were (25: 50: 25%), (50: 25: 25%), and (25: 25: 50%), respectively. Each brick series was fired at 900,
1000, 1100, and 1200oC. 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
clay-brick. From the obtained results, it was concluded that by operating at the temperature commonly
practiced in the brick kiln, a mixture consists of 50% of sludge, 25% of SF, and 25% of RHA was the
optimum materials proportions to produce brick from water sludge incorporated with SF and RHA. The
produced bricks properties were obviously superior to the 100% clay control-brick and to those available
in the Egyptian market.