Incorporation of furnace-treated alum and textile sludge in concrete: strength, durability and environmental impact

Landfilling sludge from water treatment and textile industries poses significant environmental challenges. This study evaluates the use of furnace-treated alum sludge (AS) and textile sludge (TS) as partial fine aggregate replacements in concrete. Mixes with 0%, 5%, 10%, and 15% replacements were assessed for mechanical and durability properties. At 10% AS and 15% TS replacement, compressive strength improved by 12% and 16%, respectively, compared to control. TS replacements also enhanced acid resistance and reduced water absorption by up to 18%, attributed to pozzolanic reactions and improved particle packing. All mixes met Indian drinking water standards for leachability, with only 15% AS exceeding Cu and Al limits. Slight pH reductions with AS incorporation did not affect concrete alkalinity significantly. These findings demonstrate the potential of furnace-treated AS and TS in producing sustainable, high-performance concrete.