Flume Wastewater Treatment and Reuse Using the Anti-Fouling Membrane System

An innovative anti-fouling membrane filtration system was applied for reuse of process water at two fruit/vegetable processing facilities. At the first facility, vegetables are washed in a large flume, and the flume water rapidly becomes soiled with solids, requiring frequent water change-outs. The anti-fouling membrane system fitted with an ultrafiltration (UF) membrane was tested to continuously filter the process water, reducing solids and preventing microbial growth. An on-site pilot system was installed after successful bench-scale testing, and it achieved a flux of 46 gallons per square foot of membrane per day (GFD) while producing a permeate quality suitable for reuse in the flume. The second facility operates a fruit washing flume. The anti-fouling membrane system was tested with the goal of meeting rural reuse standards for fruit wash water (50 mg/L total suspended solids and 150 mg/L chemical oxygen demand). The nanofiltration (NF) membranes tested were able to meet both goals, and the UF membranes were able to meet the TSS goal. The flux was 30 GFD for the NF membrane and 32 GFD for the UF membrane for treatment of fruit flume water.