Uso de esgoto sanitário tratado em Reator de Batelada Sequencial na produção de pasta de cimento e concreto

Abstract

The civil construction is one of the sectors of industry in which more potable water is consumed and, given water’s increasing scarcity, the use of effluents from sewage treatment plants is an alternative source for construction techniques that do not require potable water. Therefore, this work is analyzing the technical feasibility of the use of domestic sewage treated effluent in SBR (Sequencing Batch Reactor), which is located at the experimental facilities of the BRAMAR Project at the Mangabeira Sewage Treatment Plant, managed by CAGEPA (Water resources and Sewers Company of Paraíba), located in the municipality of João Pessoa - PB, with the purpose of producing cement paste and concrete. Initially, the components of concrete were defined and characterized for the determination of the best material proportion. Later, three specimens of the SBR effluent were collected, in distinct days, and chemical analyzed according to the standard NM 137. The maximum levels of pH, total iron, total solids, chlorides and soluble sulfates were verified. Then, for each specimen of treated effluent, four pairs of cylindrical test samples were cast. To make a result comparation, others four pairs were cast with water supplied by CAGEPA, totalizing 32 elements. After the moldings, the setting time and compressive strength at 7 and 28 days for all the cylindrical samples were analyzed. Thus, the results from the chemical analysis of the effluents were suitable for its use, as well as the results of the setting time and resistance tests were within the limits and tolerances required by NM 137, allowing the use of reuse water/effluent in the production of cement paste and concrete.