A large quantity of sludge is generated each year from water
treatment plants in Egypt. Disposing the sludge to the nearest water stream is the
common practice in Egypt, 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 because 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 clay and water treatment plant sludge,
this study focused on the reuse of sludge in clay-brick production. The study
investigated the use of sludge as partial substitute for clay in brick
manufacturing. In this study, four different series of sludge and clay
proportioning ratios were studied, which exclusively involved the addition of
sludge with ratios 50, 60, 70, and 80 percent of the total weight of sludge-clay
mixture. Each series involved the firing of bricks at 950, 1000, 1050, and 1100 o
C, giving 16 different brick types. The physical properties of the produced
bricks were then determined and evaluated according to E.S.S. and B.S. The
results indicated that by operating at the temperature commonly practiced in the
brick kiln, 50 percent sludge was the optimum ratio, in the sludge-clay mixture,
to produce brick from and 80 percent was the maximum practical sludge ratio.
The produced bricks properties were superior to those available in the Egyptian
market. |
