Analysis of the generation and physical-chemical characteristics of slag from the recycling of lead-acid batteries

Abstract

The lead produced in Brazil comes entirely from the lead-acid battery recycling industry. During the process, 100 to 350 kg of slag is generated for each ton of metallic lead produced. This large amount of waste generated causes serious environmental problems, where reuse and reducing toxicity are measures to resolve its negative impact. Thus, the work methodology adopted was a bibliographic survey addressing the battery recycling process (pyrometallurgy), presenting data, and discussing the toxicity of slag, its generation, its physical and chemical characteristics, and the possible waste environmental impact if not treated and disposed of properly. The results show that lead slag contains some toxic elements, such as lead, zinc, and cadmium, and that if it is not disposed of properly, it will become a paramount environmental problem. Lead slag contains large amounts of silicon, calcium, iron, copper, and other value-added metals, which can be reused as secondary resources. Thus, improper disposal of lead waste can cause critical waste of resources. This article highlights the problems that need to be faced to guarantee the industry’s sustainable development, seeking to reduce the use of inputs and natural resources and minimize environmental problems.