Glossary
Dairy and food processing

What is Effluent treatment plant (ETP)?

Definition

An effluent treatment plant (ETP) treats industrial wastewater from a factory before it is discharged or reused. In dairy and food plants, an ETP typically removes fats, solids and organic load through screening, equalization, biological treatment and clarification, and it is itself a large energy and chemical user.

What it is

An ETP takes process wastewater, cleaning water and floor wash from a factory and treats it to meet discharge or reuse requirements. Common stages are screening, oil and grease removal, equalization, biological treatment such as activated sludge or anaerobic reactors, clarification and sludge handling.

Biological treatment depends on aeration, and aeration blowers are often the largest electrical load in an ETP. Equalization tanks smooth out surges from production and CIP, so how the plant operates upstream affects how well the ETP performs.

An ETP is different from a sewage treatment plant (STP), which treats domestic wastewater. Many campuses run both, plus RO or tertiary treatment for reuse.

Who it applies to / where it is used

ETPs are required at most dairies, food and beverage plants, textile, pharmaceutical and chemical units. In India, consent to operate from the state pollution control board usually sets the treatment and discharge conditions.

How it is measured / what evidence it needs

ETP evidence covers what came in, what went out and what it cost to treat. Flow, quality and energy are all needed.

  • Inlet and outlet flow
  • Inlet and outlet BOD, COD, suspended solids and oil and grease
  • Aeration blower energy and dissolved oxygen
  • Treated water reused versus discharged
  • Sludge generated and chemicals dosed

How Aqueduct helps

Aqueduct treats the ETP as part of the plant water balance and energy picture, not a separate island.

  • aQ WaterGuard meters inlet, outlet and reuse flows so treatment losses and reuse are visible
  • aQ EnergySmart tracks blower and pump energy per cubic meter treated
  • Where control is enabled, with owner approval, blower schedules can follow measured oxygen demand
  • Alerts flag inflow surges that trace back to production or CIP
Questions

Effluent treatment plant (ETP): common questions

An ETP treats industrial process wastewater. An STP treats domestic sewage from toilets, kitchens and showers. Factories often run both.

Aeration for biological treatment is usually the largest electrical load, followed by pumps and sludge handling.

Measure inflow, quality and energy together, reduce product losses upstream, and match aeration to actual oxygen demand. Reusing treated water also reduces fresh water intake.

No. Aqueduct supplies metered flow, quality and energy data and recommended actions. The plant team or its operator runs the ETP.

See Aqueduct on your own facility.

Bring a site, a utility bill or a question. We will show you where the loss is.