Assessment of a full-scale solid-state anaerobic co-digestion: A multi-component substrate analysis by using ORWARE

Area of Science:

• Biotechnology and Bioengineering
• Environmental Science
• Sustainable Energy

Background:

• Sustainable biogas production necessitates exploring alternatives to food waste, aligning with the 2030 Agenda.
• Horse manure (HM) is abundant in Sweden and suitable for biogas production via anaerobic digestion (AD).
• Investigating HM's impact on methane yield and digestate quality is crucial for optimizing biogas processes.

Purpose of the Study:

• To evaluate the effects of different substrates and their combinations on the anaerobic digestion (AD) process.
• To assess the feasibility of using horse manure (HM) as a co-substrate in solid-state anaerobic digestion (SS-AD).
• To analyze multicomponent substrate digestion at the elemental level using the ORWARE AD model.

Main Methods:

• Application of the modified ORganic WAste REsearch (ORWARE) anaerobic digestion (AD) model.
• Simulation of solid-state (SS)-AD processes with various substrate combinations.
• Elemental-level analysis of multicomponent substrate digestion.

Main Results:

• Replacing green waste (GW) with horse manure (HM) and wood chips enhanced energy turnover.
• The liquid digestate fraction from the HM and wood chip mixture showed the highest nutrient concentrations (total carbon-biological and phosphorus).
• Digestate nutrient levels met SPCR120 certification standards.

Conclusions:

• Horse manure (HM) is a viable and beneficial feedstock for sustainable biogas production.
• Co-digestion of HM with wood chips in SS-AD optimizes energy recovery and produces high-quality digestate.
• The findings support the use of HM as a valuable resource in biogas initiatives.