Review on Characteristics of Sewage Sludge Ash and Its Partial Replacement as Binder Material in Concrete

The recent environmental concerns have made the concrete technologists think of alternatives to cement or by partially or completely replacing it with pozolonas. There is developing concern all over the world about the raw materials assets utilized in the creation of concrete, and most of them are limited and exhaustible. Use of recycled solid/liquid waste is in practice from a prolonged period in civil engineering application. The solid waste from wastewater treatment plant can be utilized as fillers or supplementary cementing material for the production of eco-friendly green concrete. Sewage sludge is a by-product of a sewage treatment plant. This paper reviews the properties of, sewage sludge ash and its application as a binder material in concrete. State of the art review on the available literature pertaining to sewage sludge and sewage sludge ash is presented. Since the property of the sludge depends on the source of wastewater, a detailed report on variation in the properties reported in the literature is presented. Particle size analysis, specific surface area, chemical composition of SSA reported in various sources are discussed. Properties are discussed on the probability to be used as a potential binder for concrete making is also discussed. Physical and chemical properties in comparison with that of OPC are discussed.