Alternativas para o manejo dos materiais residuais gerados nas análises de corantes no Laboratório de Engenharia Ambiental e Controle de Qualidade: redução, classificação e pré-tratamento dos resíduos

Abstract

The development of environmental policies by government agencies led UFRN to create PROGIRES, a program responsible for waste management at the university campus. The Laboratory of Environmental Engineering and Quality Control (LEACQ), part of the Department of Chemical Engineering, uses experiments to include students in such environmental context, both in classes and in undergraduate theses. Based on the urgent need to implement a solid waste management system, this paper aims to carry out an inventory of LEACQ’s waste related to the treatment of textile effluents and to propose measures to minimize such waste, identification, segregation and possible handling. The addressed residues, for which the physic-chemical and toxicological properties were raised and labels were produced containing Hommel diagrams, are methylene blue, methyl orange, Reactive Orange 64 dye and the coal used in their adsorption practices. The methodology for the development of this undergraduate thesis was based on basic concepts of waste management, case studies with objectives like those of UFRN and current Brazilian legislation, which sought to indicate alternatives to the current method of waste management used by LEACQ. Emphasis was placed on improving the operations’ management model, the classification of waste and its preliminary treatment. Regarding waste management, it was suggested to decrease its generation by improving how activities are planned and by reducing the scale of experiments. Concerning the classification, a system of labeling of materials was proposed, in addition to the possible replacement of the storage system with returnable cylinders, for which a sizing estimation was made. Regarding the pre-treatments, the effluents’ evaporation, when safely done, to reduce their volume in tanks that use solar energy for heating was presented as an alternative, given the high costs of this process when electric energy is used instead. As for the residues’ chemical conversion, methods involving visible and ultraviolet radiation, as well as ultrasonic waves for liquids were mentioned, and, for the coal, the need for external treatments, such as incineration and gas washing, were suggested. It was concluded by discussing the consequences of the proposals put forward.