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 WTP sludge in manufacturing of constructional elements achieves
both the economical and environmental benefits. Due to the similar mineralogical composition of clay
and water treatment plant 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 silica fume (SF) to rice husk ash (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 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 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 silica fume (SF), and 25 % of rice husk ash (RHA) was
the optimum materials proportions to produce brick from water sludge incorporated with silica fume
and rice husk ash. The produced bricks properties were obviously superior to the 100 % clay control brick
and to those available in the Egyptian market. |
