Utilization of textile effluent wastewater treatment plant sludge as brick material

In the present work, the feasibility of using sludge generated in wastewater treatment plants of textile industry as a partial replacement for clay in the conventional brick manufacturing process is examined. Physico-chemical properties of the sludge and clay were studied. The characteristics of bricks with replacement of sludge (0-50 %) with an increment of 3 % were determined. All the brick samples satisfied the requirements of Indian Standards norms in terms of weight loss on ignition. The bricks with sludge up to 15 % satisfied the prescribed norms for compressive strength and water absorption. Results also showed that the brick weight loss on ignition was mainly attributed to the organic matter content in the sludge being burnt off during the firing process. The characteristics of bricks such as efflorescence, density and weight loss on ignition for bricks with replacement of clayey soil with textile sludge up to 15 % also satisfied the requirements of the Indian Standard. Thus, textile sludge up to 15 % can be effectively added to make brick material.