Análise das características de efluente industrial de curtume e das propriedades do lodo de estação de tratamento de efluentes para incorporação em blocos cerâmicos

Abstract

The exponential world population growth and, consequently, the increasing rise of their consumption habits have generated concerns about the sustainable development of the planet. Industrial solid waste from tannery is classified as hazardous by the presence of chromium from the production process of these industries. Few industrial solid wastes are reused or recycled, having as main destination the class I landfills. By proposing the reuse, it was first sought to know the residue to be incorporated. For this purpose, the analyzes reports of the industrial liquid effluents generated by a tannery were investigated and the sludge of the effluent treatment plant (ETP) was characterized by physicalchemical and microbiological analyzes, for later incorporation into red ceramics. The ceramic industry presents incorporation facility of residues to its mass and, thus, were analyzed five types of blocks: I- composed only of soil; II- with 10% of ETP sludge and 90% of soil; III- composed by 10% of ETP sludge, 20% of balloon powder and 70% of soil; IV- composed by 15% of ETP sludge, 20% of balloon powder and 65% of soil and V- composed by 20% of balloon powder and 80% of soil. In the made blocks tests of mechanical resistance, solubilization and leaching were performed. The data from the reports analyzes of the effluent confirmed that changes in the productive process modify the generated effluent, changing the influent and the effluent. However, the treatment used by the company does not meet some demanded requirements by legislation, such as quantity of suspended solids and Biochemical Oxygen Demand (DBO). The ceramic blocks had positive results for the certification tests required by ABNT / NBR 15270-3, however, none of the blocks met the standad requirement for mechanical resistance to compression tests.