Biogas upgrading : techno-economic evaluation of different technologies based on Norwegian potential of raw materials

Abstract

This thesis comprises a literature study of the Norwegian potential for biogas production from food waste, fish processing waste and manure, in addition to an evaluation of different technologies for biogas upgrading.

The study shows that the theoretical potential of waste and residues for biogas production is around 6 TWh, of which 2.3 TWh are considered a realistic part of the potential within 2020. This is enough to cover approximately 4% of the total fuel demand associated with the Norwegian transport sector.

To evaluate the technical aspects of biogas upgrading technologies, a multi criteria analysis was used. The basis for this evaluation is data adapted from operating biogas upgrading plants in Norway as well as Europe, in addition to an in-depth literature study. This evaluation shows that for the given sets of criteria, the organic chemical scrubbing technology, often named amine scrubbing, is the best choice.

Furthermore, an economic evaluation was conducted with the purpose of estimating the production cost of amine scrubbing. The results state that the total cost of biogas upgrading is 1.26 NOK/Nm3 of produced biomethane. The most decisive cost element was electricity and an evaluation of the effect of varying electricity prices was carried out. In addition, an evaluation of the effect of varying natural gas price and cost of raw biogas production was done to provide a broader view of the whole biogas value chain.