Aplicação do biocarvão proveniente de resíduos de biomassas no tratamento de águas residuárias

Abstract

Wastewater encompasses all waters used in various processes and discarded with altered quality, including domestic, industrial, agricultural effluents, and infiltration waters. They may contain chemicals and microorganisms harmful to human health and ecosystems, requiring treatment to mitigate adverse environmental impacts. While basic sanitation in Brazil has advanced since 1970, a significant deficit in access to wastewater collection and treatment still persists. In this context, biochar has emerged as a promising and sustainable treatment alternative, since it has a porous surface similar to activated charcoal, but with lower energy consumption and costs. Biochar can be derived from carbonized biomass originating from solid waste and agricultural biomass. The objective of this study was to assess the applicability of biochar from diverse biomass sources in wastewater treatment, through a critical literature review. Studies involving biochars derived from orange peel, green coconut husks, beach almond leaves, woody plant residues, and sludge were highlighted. From the analyzed studies, it is evident that biochar generally yields favorable results in contaminant removal, such as 100% adsorptive capacity for pharmaceuticals and 46% removal of tartrazine. Furthermore, it was observed that the different biomass and pyrolysis conditions influences biochar's physicochemical properties, such as specific surface area, active functional groups, relatively structured carbon matrix, pH, and porosity. These properties are of great importance for the use of biochar in wastewater treatment, highlighting the importance of selecting the appropriate raw material for its production, according to the specific requirements of the intended application. Biochar can represent a sustainable, simplified, and cost-effective alternative for removing contaminants from wastewater, as evidenced by the use of orange peel-derived biochar, which repurposes a byproduct that would otherwise be discarded. However, it is important to encourage local income generation, foster startups, or establish internal departments within companies that intend to use biochar in effluent treatment or provide the product or service.