Hybrid electrolysis and membranes system for apple packing houses water treatment

Abstract

The apple industry uses high flows of potable quality water to transport and clean the apple, which is regularly contaminated. Thus, it is necessary to implement an efficient water treatment system during the industrial process, providing reductions in the intake and release flows. A hybrid system was developed by applying the electrolytic treatment by electrocoagulation using a batch process (Step 1) and a continuous process (Step 2), followed by a microfiltration membrane separation (MSP) process (Step 3). The optimal conditions for removal of organic matter, chemical oxygen demand, total suspended solids (TSS), turbidity, color, and fungi obtained in Step 1 were a hydraulic detention time of 40 min, stirring at 40 rpm, current density of 20 A/m2, pH of 8.00, and temperature of 10 °C. These findings led to a successful implementation in Step 2, which evolved into Step 3, where tests in the combined continuous electrolytic reactor together with MSP showed significant removal rates, notably reaching up to 54% organic matter (OM) removal, 72% chemical oxygen demand (COD) removal, 83% TSS removal, 92% haze and color removal, and 100% mildew removal. The hybrid system proved to be a promising alternative for implementation in the processing industry, minimizing environmental impacts and costs. HIGHLIGHTS Electrocoagulation associated with the separation process by the microfiltration membrane demonstrated efficiency in the removal of pollutants.; The hybrid system proved to be a promising alternative to prolong the life cycle of water in the apple processing industry.; This study contributes to the reduction of input and output flows, minimizing environmental impacts and costs during the industrial processing of apples.;

Keywords

• apple industry
• electrolysis
• hybrid system
• membranes
• pollutant removal
• water treatment