Nutrient recovery from digested waste: Towards a generic roadmap for setting up an optimal treatment train

Area of Science:

• Environmental Science
• Chemical Engineering
• Agronomy

Background:

• Wastewater treatment plants are transitioning to water resource recovery facilities.
• Nutrient recovery from digestate is crucial for a circular nutrient economy.
• Developing effective nutrient recovery strategies requires local adaptation.

Purpose of the Study:

• To develop a generic roadmap for nutrient recovery from digestate.
• To provide decision-support for implementing bio-based fertilization strategies.
• To optimize nutrient recovery treatment trains for wastewater utilities.

Main Methods:

• A guideline-based decision-tree for bio-based fertilization strategies.
• Guidelines and criteria for evaluating bio-based fertilizer production feasibility.
• A conceptual decision-making algorithm for configuring nutrient recovery treatment trains.

Main Results:

• Identification of key digestate characteristics for nutrient recovery.
• Essential factors for monitoring and control of nutrient recovery processes.
• A framework to support utilities in implementing nutrient recovery strategies.

Conclusions:

• The roadmap facilitates the transition to water resource recovery facilities.
• It supports the adjustment of nutrient recovery strategies to local markets.
• Accelerates the shift towards a bio-based circular nutrient economy from fossil reserves.