Abstract
The study performs a material flow analysis of the flows containing carbon of a Norwegian paper mill. Both the dry matter and the carbon flows are quantified. The results of the quantification is used to develop a model of the mill. The results of the modelling show a significant potential for the mill to increase both its energy and material efficiency while reducing the carbon emissions at the same time. The re-use of secondary heat to dry the bark used as fuel of the boilers at the mill show a great potential in reducing the amount of non-biogenic emissions of the mill. Removing the recycling paper line of the mill will reduce the amount of direct carbon emissions but will shift most of them outside the system. The four scenarios developed for the study show that the combination of both the removal of the recycled paper line and the drying of bark can reduce the carbon emissions of the boilers by 23.5% and the overall direct carbon emissions of the mill by 18.6%. Drying the bark showed the most potential in reducing the fossil fuel consumption of the mill. Increasing the dry content of the bark to 70-75 % is enough to phase out most of the oil used by the mill. Increasing the energy recovery of the TMP also showed a huge otential in reducing the direct carbon emissions of the mill which could reach a 30% lower value.