Foto: Viktoria Wiklicky
Titel: Livscykelanalys av fluglarvskompostering under storskaliga sve
Title:Life Cycle Assessment of Large Scale Fly Larvae Composting in Swedish Conditions
Credits: 30 credits
Subject: Technology or environmental science
Start: As soon as possible
Fly larvae composting (FLC) is a relatively new and very efficient food waste treatment method. The treatment is performed using black soldier fly larvae (Hermetia Illucens). The larvae are very efficient in extracting the nutrients available in the food waste and accumulating them in their own biomass. The treatment lasts for two weeks, after which the larvae are separated from the residue. The residue can be used in the same way as traditional compost, however it is more rich in nitrogen. The larvae can be utilized in different ways. Optimally they can be used as feed for production animals, fisheries and as pet food, but current legislation limits their use. In current legislation the larvae grown on food waste can be used as pet food, as source of raw materials such as proteins, oils and chitin and as high quality substrate for biogas production. Within a short time the larvae grown on vegetable substrate will be allowed to be used as feed in fish farming and possibly in poultry production.
Research on FLC has been performed regarding the substrate conversion and larvae composition. Research on the environmental impacts of FLC and especially on the energy demand and GHG emission in large scale waste treatment is still very limited. Large scale FLC is in the phase of implementation in Sweden with a pilot scale treatment plant being established in Eskilstuna at the Eskilstuna Strängnäs Energi och Miljö AB waste treatment facility. Part of the implementation of this pilot project is to perform the LCA of FLC food waste treatment. This master thesis will provide a large contribution towards this assessment.
The Environmental Engineering group have been performing research on FLC in many years, and have accumulated the necessary data to perform an LCA study of the FLC waste treatment system.
The emission data from two projects will be analyzed. The aeration demand estimated in another project will be used as a ground for evaluating energy demands of the pilot project being established at Eskilstuna. The temperature data from previous experiments will be used to estimate the heating demands during different seasons in Swedish conditions. The different use cases of larvae will be compared based on the examples presented in the background section.
The expected area of study would be to calculate the greenhouse gas emissions and primary energy use form large scale fly larvae composting in relation to other waste treatment alternatives like anaerobic digestion and composting. Since this treatment method has the potential to produce animal feed from waste, this would be an important focus of the study.
Competence and experience
Previous experience of LCA and/or waste management is desirable, but not compulsory.