Utilization of Water Treatment Sludge as a Filler Material in Bituminous Mix Design

The water supply of densely populated Ernakulam City of Kerala is carried out from Water Treatment Plant in Aluva, working under Kerala Water Authority. The plant with a capacity of 200 MLD, produces abundant sludge, which is usually disposed by pumping it into the river Periyar. As a sustainable method, utilization of water treatment sludge in pavement design is considered for the study. The water treatment sludge can be effectively used as a filler material in bituminous mix. Conventional filler material is replaced by sludge in 25, 50, 75 and 100% by mass. Trial specimens are prepared by incorporating the sludge in varying percentages. To study the optimum binder content and stability, Marshall Stability flow value test is conducted. The adhesion properties of the mix are understood through the Cantabro test. Comparing the results of Marshall stability test and Cantabro test, bituminous mix with 25% sludge replacement proves sufficient property to be implemented in public works, which can be considered as a sustainable alternative to the current method of disposal.