EVALUATION OF THE USE OF SEWAGE SLUDGE ASH (SSA) AS PARTIAL SUBSTITUTION TO THE USE OF CEMENT IN CONCRETE MIXTURES

Abstract

There are many difficulties related to an adequate final disposition of the sewage power plant waste, leading to high expenses to Sewage Treatment Stations (ETEs) concessionaires. In this work, it was proposed to use sludge ash from the sewage treatment, calcined and incinerated at 400º C, as a partial replacement for Portland cement in the conventional concrete mix. The first stage of the research was the physical characterization of the constituent materials of the concrete and the ash of the sludge. It was followed by the physical and mechanical tests of conventional concrete and traces of concrete with addition of ash in the proportions of 5, 7.5 and 10%. The results of ash traces were analyzed and compared to the conventional concrete traces, and the substitution in the proportions of 5% and 10% were the best options, concluding that it is feasible the use of sewage sludge ash for the civil construction.