Rejeitos De Mineração: Um Olhar Do Cenário Brasileiro - Parte I: Cadeia Produtiva

Abstract

Resumo O Brasil figura como uma das grandes potências minerais do mundo, sendo esse setor de grande valia para a economia brasileira por gerar milhares de empregos diretos e indiretos. Apesar de sua importância econômica e social, a atividade da mineração ocasiona uma grande geração de rejeitos. O país é detentor de um robusto arcabouço legal, com uma série de regulamentações a respeito do meio ambiente no setor mineral, sendo que 14 delas são específicas para rejeitos da mineração. No entanto, o acidente ocorrido com a barragem da Samarco em 2015 trouxe novamente à pauta a temática dos rejeitos, o que tem instigado uma série de discussões na cadeia da mineração. Neste trabalho, os autores procuraram caracterizar três aspectos: o cenário atual da cadeia produtiva da mineração, a problemática da geração de rejeitos e o nível de desenvolvimento tecnológico que visa o seu aproveitamento. Esse conteúdo está estruturado em duas partes. A primeira parte, retratada neste documento, analisa a cadeia produtiva da mineração e a dinâmica que caracteriza a participação de seus vários atores, assim como as formas de aumentar os investimentos em processos de recuperação de rejeitos.

State of the Art of the Use of Mining Tailings in Road Pavements

“…A search was performed for current data on iron ore tailings production, but no results were found. However, considering the values published by Moraes et al (2017), where the number of iron ore tailings generated corresponded to 26.7% of its annual production, it can be concluded that more than 100 million tons are generated per year. In this work, the use of iron ore tailings in pavements was divided into 6 classes:…”

“…Of the 70 mineral substances produced in Brazil, only 15 correspond to about 90% of the national gross production, also characterizing themselves as the most important generators of tailings and, in 15 years, they were responsible for the origin of about 4.86 billion tons of accumulated tailings, with the production of iron, gold, and phosphate representing 58% of the total generated (MORAES et al, 2017).…”

“…According to Moraes et al (2017), each person consumes around 5.4 tons of inputs of mineral origin per year, reaching about 328 tons in 70 years of life, which would result in 3,000 tons of tailings per inhabitant. Considering the current Brazilian population of 213 million inhabitants, this implies a total of over 9 billion tons of waste generated annually!…”

“…The search for technologies that result in the use of tailings efficiently could reduce the number of tailings disposed of in dams. According to Moraes et al (2017), many studies using the tailings generated by mining have been carried out in Brazil and several countries around the world, and in the last 15 years, more than 500 articles involving mineral substances produced in Brazil have been identified. In 2017, the mining theme was the subject of research in 41 Science, Technology, and Innovation institutions spread across 17 Brazilian states, with emphasis on the State of Minas Gerais, one of the main producers of ores in the country.…”

“…In 2017, the mining theme was the subject of research in 41 Science, Technology, and Innovation institutions spread across 17 Brazilian states, with emphasis on the State of Minas Gerais, one of the main producers of ores in the country. The number of research groups studying the mining topic was 68, and there were 25 lines of research directly related to the reuse of tailings (MORAES et al, 2017). The research approaches the application of tailings in several areas, such as in civil construction and, particularly, in road engineering, in pavement works, where the main tailings studied come from iron, bauxite, copper, and tungsten ores.…”