Beneficiation of water works sludge for environmental sustainability

Abstract

Water Works Sludge collected from a water treatment plant was beneficiated for environmental sustainability. The steps considered
were gravity thickening and air drying incorporating mechanical agitation. Results of tests conducted showed that the combined
effects of temperature, relative humidity, wind speed and sun intensity affect the dying rate of sludge. Additionally, high solid
content of 80% was achieved at a reduced time using drying bed which was high compared to the value from other dewatering
processes. This study showed that water works sludge consists of typical oxides of alumina and silica, and can be properly managed
in the environment through the manipulation of process parameters and incorporation of mechanical agitation that cushion the effect
of sludge depth while improving the performance of drying bed. Considering the high potentials for resource utilization, sludge can
be adopted as secondary raw material for building, construction and mining industries, while checking the menace of environmental
degradation.