Design of a Wastewater Treatment Plant for Agroindustrial Bins Washing: Technical, Economic, and Environmental Evaluation

Resumen

Agro-industrial fruit processing operations require large volumes of water, especially during flotation, washing, and container cleaning processes. These activities generate wastewater containing suspended solids and organic matter which, with proper treatment, can be reused within the production cycle. This project presents the design and techno-economic evaluation of a wastewater treatment plant intended to enable the reuse of water generated during the fruit flotation and washing stages in a Chilean agro-export company. The treated water is subsequently reused for washing agricultural containers used for transporting and handling fruit. The wastewater produced in these operations contains a mixture of leaves, branches, soil particles, partially decomposed apples, and traces of an anionic detergent used during the washing process. To address these characteristics, the proposed treatment system integrates a screening stage, clarification using inclined plates, and activated carbon filtration to remove suspended solids and improve water quality. The system was designed considering an operational water consumption of approximately 10,000 L every three days, equivalent to almost 100 m3 per month. The results indicate that implementing a compact treatment configuration with a relatively low investment and rapid payback can significantly reduce freshwater consumption and minimize wastewater discharge, thereby contributing to more sustainable water management in agro-industrial operations.