Avaliação do cromo contido em resíduo sólido de laboratório e materiais solidificados e estabilizados para confecção de blocos.

Abstract

The residues generated in the universities represent 1% of the total waste in relation to other sources of solid waste, but they present difficulties in the treatment due to the quantity and diversity of compounds present in a single residue. Residues are classified according to flammability, corrosivity, reactivity, toxicity and pathogenicity (Class I) or biodegradability, combustibility or water solubility (Class II A or Class II B) characteristics. When classified as hazardous they cause damage to health and the environment. An alternative treatment is stabilization by solidification, which promotes the incorporation of the residues to cementitious matrices. The main objective of this work is to perform the evaluation of the heavy metal Chromium contained in the Solid Waste of Laboratories for use in Blocks without structural function. In the experimental procedure, the planning was adopted in the one-way type design with regression analysis.The first step consisted in determining how much was released from chromium to the environment, from the leaching test; the crude laboratory solid waste was classified in class I. To define the best range of residue incorporation, test specimens were prepared for preliminary tests.The test specimens were made with pozolonic Portland cement, fine sand, gravel and passive solid waste from the chemical engineering laboratory (RSL), which were submitted to leaching tests to classify them. From these, the percentages of 5, 20 and 35% RSL were defined, followed by integrity / durability tests and immobilization of contaminants.The best results of all the analyzes were found for incorporation of 5% (RSL). The matrices with 5 and 20% passed from class I to class IIB, the matrix with 35% was approved in the integrity / durability test, but failed in the leaching test with 0.09mg / l of chromium above the maximum limit.