Tratamento de resíduo sólido de laboratório contendo zinco e cobre e simulação do processo de estabilização por solidificação.

Abstract

The intense generation of solid waste remains one of the major environmental problems today. Higher education institutions are also responsible for this increase because they have different composition residues that are discarded in an inadequate manner. In view of this reality, the present research aims to carry out the treatment of laboratory solid residue containing zinc and copper and to simulate data of the solidification stabilization process. The methodology was developed in five stages, in the first stage the classification and characterization of LSW (Laboratory Solid Waste), cement and sand were carried out. In the second one, experimental design was done, with a factorial type with 5 central points added. The factors adopted were percentage of LSW (5 and 15%) and cure time (7 and 28 days). In the third stage the fabrications of the cementitious test matrices were carried out and, later, matrices according to the experimental design. In the fourth stage the SS material was evaluated, through tests of integrity and durability and immobilization of the contaminants. In the fifth stage, the data processing was performed, obtaining the model of the significant tests (proposing simulations of the data in order to compare the actual data obtained experimentally with the data obtained through the simulations). The characterization of the materials showed high concentrations of fixed solids, 98.97%, 98.94 and 79.74; for cement, sand and LSW, indicating high content of inorganic material, respectively, in the materials. On the other hand, the classification of RSL presented levels of Copper (350 mg.L-1) and zinc (397 mg.L-1) above the limits set as permissible for disposal in the environment, classifying it as Class I (hazardous), which needs prior treatment before being disposed of in the environment. As a result of this study, it was observed that all treatments were approved in the tests of integrity/durability and immobilization of the contaminants, making the conversion of class I (hazardous) to Class IIB (non - hazardous - inert). The obtained models were significant for the resistance to compression, humidification/drying and solubilization of copper and predictive. The best results were obtained with the experiments that used less percentage of laboratory solid residue and shorter curing time. This work allows to affirm that it is possible to treat LSW through the solidification stabilization process and that the introduction of environmental assessment limits contributes to ensure adequate disposal of waste and adequate use of the final product.