ABSTRACT
Sludge dewatering is a process to removes the moisture from sludge making it simpler and more economic to transport and disposal. Dewatering is mainly accomplished by drying beds or a physical process, which removes water from the sludge through presses or centrifuges. Natural methods rely on natural evaporation and percolation to dewater the solids, while artificial methods use mechanically assisted physical means/devices to dewater the sludge more quickly. Many sludge factors affecting the dewatering characteristics of sludge have been reported in the literature. Sludge drying beds are constructed on the ground and commonly characterised by the nature of the bed. Gravity drainage is responsible for removal of the free or gravitational water content of sludge moisture by the force of gravity. Mechanical methods may be used to dewater raw sludge or a mixture of raw and digested sludge preparatory to heat treatment or before burial or landfill.
