Tratamento de lixiviado de aterro sanitário por processo de eletrocoagulação

Abstract

With the continuous population growth observed in recent decades, the demand for consumer products has increased, consequently leading to a rise in the amount of Municipal Solid Waste (MSW) sent to sanitary landfills. These landfills, due to the percolation of rainwater and the decomposition of organic matter, generate landfill leachate (LL), which contains various organic pollutants that are difficult to remove and pose a threat to environmental health if not properly treated. Therefore, this study aimed to evaluate the efficiency of the Electrocoagulation (EC) process in removing pollutants present in LL. Initially, raw leachate was characterized based on physicochemical parameters such as absorbance at 254 nm, electrical conductivity, and potential of hydrogen (pH), revealing a medium-aged landfill effluent with a significant presence of organic compounds. Preliminary tests were conducted using different electric current intensities (3, 6, 12, and 18 Ampere (A)), with 6 A being selected for the main experiments due to its good contaminant removal performance and lower energy consumption. In the experimental tests, absorbance, conductivity, and pH were monitored over time, confirming the process's effectiveness in reducing organic matter and altering the physicochemical properties of the LL. However, toxicity bioassays with Artemia salina indicated high residual toxicity, with considerable larval mortality, suggesting the presence of contaminants even after treatment. The results demonstrate that, although electrocoagulation significantly improves leachate quality, complementary methods such as biological processes are necessary to enhance the removal efficiency of toxic substances.