Avaliação ambiental dos resíduos sólidos oriundos da produção de couros no Rio Grande do Sul

Abstract

Rio Grande do Sul state concentrates around one third of productive leather units in Brasil, which has a significant role in this sector. Finished leather production starts with the skins obtained from slaughterhouse and consumes a large amount of water and a great number of chemical products, combined with different mechanical operations. It results not just in the desired product, but also in different kinds of waste, causing significant environmental impacts. Among the produced wastes, solid ones stand out, mainly due to its large amount and their pollutant potential. Even though enterprises from Rio Grande do Sul are forced to regularly issue and submit a report on produced and allocated solid waste to the environmental commission agency, there is not available information about typologies and solid waste produced in the state of Rio Grande do Sul, and the last inventory dated 2002. Knowledge about waste production and its disposal is very importance in order to support decision making on the present subject, either to create public policy and decide where to invest, or to define in which areas technical and scientific efforts must be performed. Management environmental evaluation of solid waste from leather production in Rio Grande do Sul consists in a qualitative and quantitative exploratory research, creating a case study about the leather sector management in the state. This dissertation includes a brief presentation on leather production process, its aspects and environmental impacts, the solid waste generated, treatment technologies and its final disposal, with emphasis on forms of recovery through recycling processes, upcycling and down cycling, considering the generation of possible byproducts and coproducts for the leather industry. It also addresses waste management assumptions, legal requirements and applicable opportunities from Cleaner Production to solid waste management. From “Sistema de Gerenciamento e Controle de Resíduos Sólidos Industriais” – SIGECORS of 2013 and 2014 (FEPAM, 2016A) it was observed an annual generation of 112,642.5 tons plus 129,107.3 cubic meters of waste. In addition, it was found a generation of 88,877 units (packaging and light bulbs), and the dangerous waste production was slightly lower than the non dangerous ones. The main solid wastes generated, in quantitative terms, come from pollution control systems (especially sludge from effluent treatment stations), followed by leather wastes (basically tanned via chromium) and by wastes from skins (in processes performed before tanning). About non dangerous wastes – Class II, it was found that recycling practices, upcycling and down cycling, which results in coproducts and byproduct, achieved a performance higher than 95%. About the dangerous wastes – Class I, the reclamation was lower (however much higher than the registered standard in 2002) and the produced sludge from effluent treatment stations is the most problematic waste in the sector. There is not yet an available alternative to recycling. By the environmental evaluation performed, it is concluded that environmental differential in this sector in Rio Grande do Sul is in the systemic application of waste appreciation processes, which includes reuse of waste, upcycling execution, transforming waste in coproducts, recycling, and down cycling execution, transforming waste in byproducts.