Maximizing the utilisation of the nutrient and energy potential of sewage sludge

Activities

The Y-MAX project covered the entire value chain of municipal sewage sludge, from sludge to the final treatment of digestate after biogas production. The project consisted of six work packages:

WP 1. Project coordination and communication

The project and its results were presented at several events and in a final webinar. The results have been compiled in the final publication, which can be found at: https://urn.fi/URN:ISBN:978-952-344-634-2

WP 2. Regulations, symbiosis and commercialization

The operation of biogas plants is governed by legislation that is continuously being updated. Finnish Water Forum carried out a comprehensive study on the regulations affecting the biogas sector as well as upcoming updates.

The biogas sector has growth potential both in Finland and internationally. Intolead assessed the commercialization and export opportunities for the technologies, with particular focus on South Africa.

WP 3. Characterization, measurement and monitoring

Reliable real-time measurement data play a key role in process management. Valmet developed measurement technologies for biogas processes and created basis for a control and optimization concept that supports resource-wise and energy-efficient operations.

WP 4. Nitrogen removal and recovery

Chicken manure contains high nitrogen levels, which can inhibit gas production. Using Ductor’s nitrogen recovery method, part of the nitrogen was recovered from the chicken manure before the actual digestion process.

WP 5. Fraction characterization & optimization of sludge and digestion

A special interest in the anaerobic digestion process was the co-digestion of municipal sludge and chicken manure. Xamk performed laboratory and demonstration scale tests, where the goal was to increase biogas production by utilizing chicken manure
as an additional energy source.

WP 6. Digestion disposal and nutrient recovery

Sludge drying is a key factor in the functionality and cost-efficiency of wastewater treatment processes. Dewaco studied the optimization of solid–liquid separation of digestate after biogas production and tested the mechanical drying of the digestate using a belt filter press.