Biocarvão de resíduos de laranja como meio filtrante para tratamento de efluente doméstico visando reúso agrícola

Abstract

Brazil stands out as the world's largest producer of oranges, generating a significant volume of byproducts from the agro-industrial sector. In order to make use of these resources, the production of biochar from orange waste emerges as a promising alternative, especially for its use as a filtering medium in wastewater treatment systems. The objective of this study was to evaluate the impact of temperature on biochar production and to characterize the resulting material for application as an adsorbent in filtration systems for agricultural reuse. The pyrolysis process for biochar production was conducted at temperatures ranging from 350 to 650ºC for 60 minutes. The obtained material was analyzed for its chemical composition, crystalline structure, morphological changes resulting from the transformation of biomass into biochar, as well as the determination of surface area and average pore size. Pyrolysis tests indicated that the ideal temperature for biochar synthesis was 550ºC. The characterization results showed that the material has a high surface area and a significant increase in pore size, promising characteristics for its application as an adsorbent in filtration systems. In filtration tests with septic tank effluent, the system with orange biochar showed higher efficiency in the removal of macronutrients compared to the system with gravel. Notable removals were observed for total phosphorus (31.58%), magnesium (62.09%), and microbiological contaminants (62.09% – 76.14%). These results suggest that the treated effluent may be viable for use in certain crops, revealing a promising and sustainable alternative for wastewater treatment.