Digestate treatment for food waste plant to meet sewer discharge requirements for three locations - Reference

Project’s context & challenges

The client is transforming food waste into renewable energy and valuable resources while helping reduce food being wasted. To support this circular mission, the company required a wastewater treatment solution after digestion that could reliably manage high variable wastewater streams while meeting strict sewer discharge requirements. The client operates multiple food waste facilities, of which three are currently equipped with treatment plants supplied by NSI.

Ensuring reliable sewer discharge

The wastewater derived from food waste processing contains high concentrations of ammonia, and suspended solids. The client required future-proof treatment solutions capable of consistently meeting sewer discharge limits under fluctuating operating conditions at their anaerobic digestion locations.

Maximizing resource recovery

Beyond compliance, the client aimed to recover valuable resources from its wastewater while reducing disposal costs and improving operational efficiency. The objective was to create an integrated treatment concept that supports a circular approach to food waste processing.

Key figures

Industry:

Food waste processing | Waste to Energy

100.000 t/y

Feedstock processed

8.5 Mm³/y

Energy produced

Digestate treatment (25 m³/h)

Application

Sewer discharge

Objective

Customer benefits

Reliable compliance with municipal discharge requirements

Consistent removal of ammonia, suspended solids and dissolved organic contaminants, even during fluctuating operation conditions.

Maximized resource recovery

Recovering ammonia and enabling future water reuse supports a more circular and sustainable food waste operation.

Lower operational and disposal costs

One integrated treatment concept improves operational control while reducing disposal costs.

Future proof and scalable solution

The modular treatment approach allows facilities to adapt to changing regulations, production volumes, and sustainability objectives.

Solution

Nijhuis Saur Industries developed an integrated wastewater treatment concept after digestion (An-MBR) that combines ammonia stripping, aerobic biological treatment and advanced solids separation into one robust process.

The solution for two food waste plants combines:

Ammonia stripping (ByoFlex®) for efficient ammonia recovery.
Both Continues Aerobic activated sludge (Nijhuis BIOCTOR GD) as well a MBBR (FlooBed® MBBR) biological treatment for biological nitrogen removal.
Dissolved Air Flotation (Nijhuis GDF) for efficient solids separation.

The solution for one food waste plant combines:

Ammonia stripping (ByoFlex®) for efficient ammonia recovery.
Both Continues Aerobic activated sludge (Nijhuis BIOCTOR GD) as well as MBBR (FlooBed® MBBR) biological treatment for biological nitrogen removal.
Dissolved Air Flotation (Nijhuis GDF) for efficient solids separation.
Ultrafiltration (Nijhuis NMS-UF) and Reverse Osmosis (Nijhuis NMS-RO) for polishing of water to meet local discharge requirements.

This integrated approach ensures reliable treatment performance under varying influent conditions while closing resource loops and maximizing operational efficiency.

Scope of supply

contract type:

Design, engineering and technology supply for multiple sites

solution for two plants:

Ammonia stripping (ByoFlex®)
Biological treatment (FlooBed® MBBR)
Dissolved Air Flotation as activated-sludge unit (Nijhuis GDF)

solution for one plant:

Ammonia stripping (ByoFlex®)
Biological treatment (FlooBed® MBBR)
Dissolved Air Filtration as activated-sludge unit (Nijhuis GDF)
Ultrafiltration (Nijhuis NMS-UF)
Reverse Osmosis (Nijhuis NMS-RO)

Lifecycle services:

Engineering
Commissioning
Start-up support
Monitoring & process optimization