Life Cycle Assessment of Fluoride Removal from Mining Effluents Using Electrocoagulation and Biogenic CO₂

Industrial wastewater is a significant source of environmental pollution. This study conducts a life cycle assessment (LCA) of fluoride removal from mineral industry ef-fluents via an electrocoagulation process, incorporating CO₂ derived from biogas for pH regulation and electricity cogeneration. The LCA includes five subsystems: elec-trocoagulation, pH adjustment, sedimentation, pumping, and sludge transport. Three scenarios were evaluated: S1, which employed hydrochloric acid for pH adjustment; S2, which used biogas exclusively for pH regulation and S3, which utilized biogas for both pH control and power generation. The overall environmental impact followed the order S3 < S1 < S2, with S3 achieving approximately a 50% reduction in impact com-pared to S1. Among these, the electrocoagulation unit exhibited the highest environ-mental impact. However, in Scenario 3 (S3), the pH adjustment subsystem demon-strated a net environmental benefit due to extra electricity generation. Furthermore, the valorization of electrocoagulation sludge as a raw material for bricks contributed to additional impact reduction. Sludge reuse was implemented in all scenarios. Human health was the most affected category, with primary contributors including human non-carcinogenic and carcinogenic toxicity, global warming potential, marine ecotoxi-city, and fine particulate matter formation. The findings underscore the environmental advantages of biogas integration and sludge valorization in industrial wastewater treatment.