Lindberg, Lovisa
- Department of Energy and Technology, Swedish University of Agricultural Sciences
Black soldier fly larvae (BSFL) composting is becoming increasingly recognised as a sustainable bioconversion technology aligned with circular economy principles. However, when applied to plant-based food and agro- industry waste—such as cucumber plant residuals, orange peels, and vegetable mixes—its biological efficiency and economic viability remains unclear. This study evaluated the effects of various pre-treatments (ammonia, fungal, enzymatic) and co-substrate additions (e.g., frass) on BSFL process efficiency, greenhouse gas and ammonia emissions, and larval biomass yield across both small- and large-scale systems. Whilst fungal and enzymatic pre-treatments improved material reduction, their impact on biomass conversion efficiency (BCE) was substrate- and scale-dependent. The addition of both enzymes and frass significantly enhanced BCE and larval yield in small-scale systems but was less effective at larger scales. Direct emissions of CH4 and N2O were low relative to CO2, however, ammonia pre-treatment increased NH3 emissions. Despite reduced larval yields, BSFL composting achieved substantial waste volume reduction and partial degradation of pesticide residues. These environmental benefits suggest that the technology may still offer a viable treatment pathway for nutritionally imbalanced, fibrous waste streams, particularly where conventional composting or anaerobic digestion is unsuitable. For successful large-scale implementation, system modifications—such as improved environmental control, passive harvesting strategies, and decentralised processing models—will be essential. Overall, BSFL composting presents a promising waste management solution for plant-based residues, with potential value lying more in environmental services than in larval biomass production.
Biological treatment; plant-based waste; Hermetia illucens; pre-treatment; co-treatment; ammonia; Trichoderma reesei; enzyme; frass; Biologisk behandling; växtbaserat avfall; Hermetia illucens; förbehandling; sambehandling; ammoniak; Trichoderma reesei; enzym; frass
Acta Universitatis Agriculturae Sueciae
2025, number: 2025:85
Publisher: Swedish University of Agricultural Sciences
Other Environmental Biotechnology
https://res.slu.se/id/publ/142486