Forest Refine, 2012-2014 : efficient forest biomass supply chain management for biorefineries : synthesis report

Current biorefining activities and plans for new biorefineries in Sweden and Finland are largely concentrated on the production of liquid biofuels for the transport sector. However, the pulp industry (and other players) are also developing new biorefinery processes, for example to: convert pulp fibers into new types of materials and products (e.g. textiles, diverse composites and nanocellulose); upgrade residue streams to deliver marketable products (e.g. via black liquor gasification, lignin extraction, fermentation of hemicellulose, and gasification or hydrolysis of fibre sludge); implement processes for coproduction of process steams and marketable products (e.g. gasification and pyrolysis); and extract useful substances from incoming raw material (e.g. pre-extraction of hemicellulose). Thus, for example tall oil from pulp mills is increasingly being used as feedstock for both motor fuels and various chemicals. The raw material requirements of future biorefineries (in terms of abundance, quality and timing of supplies) may radically differ from those of traditional forest industries and energy plants, demanding equally radical adjustment of the supply chains. Thus, it is vitally important to harmonize research and development goals in parts of northern Sweden and Finland in the Botnia-Atlantica (BA) region with the development of efficient and sustainable supply chains for forest raw material. Hence, the overall objective of this project was to acquire knowledge of ways to optimize biomass supplies for refineries in the BA region from existing, planned or potential procurement areas. An overall conclusion from the studies is that supply costs can be significantly reduced by integrating supplies of pulpwood and residual assortments rather than providing them via separate supply chains. However, assessing the costs and benefits of possible systems is not straightforward as they are influenced by complex interactions between supplies of multiple feedstock assortments and demands from multiple users. Furthermore, the costs of separating stemwood from residues at a later point in the chain may reduce or eliminate the benefits of integrated harvest. Hence, the advantages would be greatest for applications in which there is little gain from separating these assortments. Available amounts of feedstock could also be increased by pre-treatment operations, which could make previously non-viable assortments available. However, any cost reductions thus achieved from increasing supplies should be weighed against the additional pre-treatment costs. Overall, the options studied in the project indicate that new practices could potentially reduce supply costs by around 10%, compared to current best practices, under certain conditions. Another critical factor is to ensure that supplies of biomasses with various qualities can be rapidly adjusted and adapted to meet shifts (potentially unpredictable) in demand. Terminals can play a key role in the provision of such flexibility. Current terminals are mainly used as transition points, where little upgrading is done apart from comminution. Since raw forest biomass cannot be transported long distances, due to its relatively low value, robust value-upgrading at terminals closer to terminals before long distance transportation is likely to be necessary. Such terminals must be quite sophisticated in order to serve as flexible/semi-mobile refineries, i.e. they will need to have access (inter alia) to appropriate infrastructure, electricity, water and personnel. As most of the unexploited forest biomass resources are located in inland areas, particular attention should be paid to developing terminal-refinery-integrated supply chains in these areas for supplying industry-dense areas for further refining or direct use in processes.