Potential Water Reuse for High Strength Fruit and Vegetable Processor Wastewater with an MBR.

Abstract

High strength food processing wastewater from two processing plants was studied to determine the effectiveness of an aerobic membrane bioreactor (MBR) to reduce BOD, TSS and nutrients below municipal sewer discharge limits. The MBR comprised a 20 L lab-scale reactor combined with a flat sheet, ultrafiltration membrane module. The parameters studied included the operational flux, solids and hydraulic retention times and recirculation ratio with regards to nitrification/denitrification. The MBR system provided excellent removal efficiency at 97% COD, 99% BOD, 99.9% TSS, 90% TKN, and 60% TP for both processing plants, which eliminated the surcharges, allowing the firms to stay competitive. Effluent reuse tests showed that activated carbon proved effective in removing color from the MBR permeate, while UV treatment was able to achieve a 5 log reduction in bacteriophage. Overall, these treatment successes show the potential for water reuse in the agrifood sector.