Activated alumina sludge as partial substitute for fine aggregates in brick making

Abstract Community water defluoridation plants primarily use activated alumina (AA) for treatment. However, this process generates toxic AA-sludge for which no sustainable method of disposal is currently known. This study evaluated whether AA-sludge could be partially used in manufacturing bricks that are structurally stable and non-polluting. The AA-sludge was variably mixed with soil (0%, 5% and 10% by weight) and fired in a field kiln to produce bricks. These bricks were extensively tested for their structural, non-structural and leaching properties. Up to 10% replacement of conventional clay soil with AA-sludge could be recommended for low-end structural applications.