Lightweight bricks manufactured from water treatment sludge and rice husks

Novel lightweight bricks have been produced by sintering mixes of dried water treatment sludge and rice husk. Samples containing up to 20 wt.% rice husk have been fired using a heating schedule that allowed effective organic burn-out. Rice husk addition increased the porosity of sintered samples and higher sintering temperatures increased compressive strengths. Materials containing 15 wt.% rice husk that were sintered at 1100 °C produced low bulk density and relatively high strength materials that were compliant with relevant Taiwan standards for use as lightweight bricks.