Sustainability in the treatment of wastewater from canning industry effluents

Abstract

The treatment of wastewater from the fish canning industry presents specific challenges due to its high organic load and elevated salt and nutrient concentrations. This study combines modelling and real-world data from an operating industrial plant to evaluate the performance and environmental impact of a wastewater treatment plant located in Galicia, Spain, which treats effluent from a tuna canning factory. The treatment setup includes physical pretreatment, dissolved air flotation, sequential biological reactor, and sludge treatment units. Based on the simulation results, a Life Cycle Assessment (LCA) was applied using the ReCiPe Midpoint (H) methodology, considering eight environmental impact categories. The results indicate that the greatest impact corresponds to the power consumption of the sequencing batch reactor for aeration, which results into 6.75 kg CO2-eq./m3. The sensitivity analysis, which included different European electrical profiles and the replacement of the coagulant polyaluminium chloride with ferric chloride, identified significant opportunities for environmental improvement. In this regard, the climate change category may reach reductions up to 4.45 and 0.38 kg CO2-eq./m3, for energy and chemical substitutions respectively. This integrated approach demonstrates the potential of combining simulation and LCA as a decision-support tool to improve sustainability in industrial wastewater treatment in the canning sector.