Experimental Investigation on Concrete by Partial Replacement of Cement with Sewage Sludge Powder and Fly Ash

Sludge is an inevitable by-product of wastewater treatment. The disposal of sludge is a complex problem that can affect air, land & environment. Thus the large scaled disposal of sludge is one of the major concerns of any municipality. Currently the most common methods of sludge disposal are ocean dumping, land filling & agricultural use. All these disposal alternatives have varying degrees of environmental impact. Therefore there is a need of alternative solutions to the problem of sludge disposal. One possible solution lies in using incinerated sludge for economical uses in construction as substitute materials. Digested and dewatered sludge, after incineration at a high temperature, yields a hard, cellular, porous mass with low unit weight. This hardened mass of sludge ash can be crushed to smaller-sized aggregates, which, when graded in suitable proportions, manifest the basic attributes required of lightweight aggregates.