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Case Study · Food Processing

Food plant effluent: 100% bacterial reduction.

Powell Water E-Cell treatment of bacterial loading in food production plant water across four source streams — total plant effluent, hot wash, ambient wash, and cold water. Caro Labs analyzed APC, coliform, and salmonella before and after treatment.

The objective

Food processing operations generate plant effluent with high bacterial loading — aerobic plate counts (APC) in the hundreds of millions of colony-forming units per gram, coliform counts at similar levels, and the periodic positive test for salmonella that creates regulatory and reputational risk. Conventional treatment for this stream typically involves chlorination or UV, both of which have operating costs and regulatory considerations.

The objective of this test was to determine whether electrocoagulation alone could achieve the bacterial reduction required for discharge or recycle — without chlorination, ozone, or UV.

Treatment configuration

The Powell Water E-Cell was operated at 100 volts with amperage varied by sample type, ranging from 1.0 to 5.3 amps depending on water conductivity and bacterial loading. Energy consumption ranged from 1.67 to 8.75 kWh per 1,000 gallons treated.

Powell Water E-Cell unit configured for food plant water treatment
Powell Water E-Cell setup for treatability testing across four food plant water sources.

Results — All Four Sources

Caro Labs analyzed each source stream before and after E-Cell treatment for aerobic plate count, total coliform, and salmonella presence. Results below.

Source APC cfu/g (raw) APC cfu/g (treated) Coliform (raw) Coliform (treated) Salmonella kWh/1000 gal
Total Plant Effluent 118,000,000 280 65,000,000 10 PosNeg 4.17
Hot Wash Water 168,000,000 10 65,000,000 10 PosNeg 8.75
Ambient Wash Water 5,200 20 430 10 NegNeg 1.67
Cold Water 40 10 10 10 NegNeg 2.50

Reductions

Plant Effluent APC
118Mcfu/g raw
280cfu/g treated
100% ↓
Plant Effluent Coliform
65Mcfu/g raw
10cfu/g treated
100% ↓
Hot Wash APC
168Mcfu/g raw
10cfu/g treated
100% ↓
Salmonella
Positiveplant + hot wash
Negativeall streams
Eliminated

Takeaway

The E-Cell delivers complete bacterial reduction across the full range of food plant water sources — from highly contaminated total plant effluent (118 million cfu/g APC) down to cleaner ambient wash water. Treatment energy per 1,000 gallons varies with conductivity and loading, but stays in single digits.

For food processors looking at alternatives to chlorination, UV, or ozone — particularly where chemical residue in recycled wash water is a concern — electrocoagulation provides a chemistry-free path to bacteriologically safe recycle water.