Much of the discussion about biomass and biofuels centres around their use for residential heating or as a replacement for fossil fuels in the transport sector. It should not be forgotten, however, that Europe’s dependence on fossil fuels is not restricted to these uses. Fossil fuels are also a key raw material in the chemical industry, and are used extensively in the production of polymers and plastics.
The aim of the EU-financed BIOCORE project, which ran from March 2010 to February 2014, was to conceive and analyse the industrial feasibility of a biorefinery concept that would allow the conversion of feedstock into a wide spectrum of products, including second generation biofuels, chemical intermediates, polymers and materials. By developing a range of polymer building blocks, BIOCORE aimed to show that 70% of polymers currently in use could be derived from biomass.
The first challenge that the project addressed was to demonstrate that a biorefinery could operate on mixed biomass feedstock. Several scenarios were generated that took into account harvest seasonality, transport and storage of biomass for biorefineries located in different regions of Europe and Asia. These scenarios were then used to analyse how a biorefinery could be stably supplied with a mixture of cereal crop by-products, forestry residues and Short Rotation Coppice (SRC) wood.1
The BIOCORE project intensively studied and optimised a pilot plant run by France-based project partner Compagnie Industrielle de la Matiere Vegetale (CIMV) S.A., which operates on organosolv technology, based on the use of a formic/acetic acid solvent. The organsolv process was tested for its capacity to use a feedstock mix comprising rice straw, hardwood and SRC wood. The studies revealed that, with some process modifications, the organosolv process can be adapted to use this feedstock mix, thereby meeting a key criterion of the BIOCORE concept.
BIOCORE developed valorisation pathways for three types of lignocellulose feedstock: wheat and rice straws; deciduous forestry residues; and SRC. Regarding the latter, a recent IEA report has estimated that in 2050 up to 1000 exajoules of SRC could be produced annually, which represents approximately 66 gigatons of biomass. The IEA also expects that energy crops, particularly SRC and miscanthus, will continue to show yield increases as new varieties are developed and commercialized.2 According to the IEA report, this biomass will be produced on surplus or marginal lands and will therefore not compete with land use for food. Moreover, SRC woody crops have the added advantage that they can be grown on polluted land that is unfit for food production, which means that biomass production can be coupled with bioremediation land reclamation programmes.
A key feature of BIOCORE is its ambition to produce several types of polymer. This is because forecasts indicate that polymers will constitute one of the most dynamic future markets for bio-based products. Furthermore, it is clear that society is highly dependent upon bulk thermoplastic polymers, such as polyolefins PVC and polyurethanes. This means that, if biorefineries are to respond to market needs, it is vital that they develop the capacity to produce bio-based polymers that meet current standards.
An overarching priority for BIOCORE was to investigate the sustainability of the BIOCORE biorefinery concept from an environmental, economic and social viewpoint, in order to identify the most sustainable biorefinery options. A study of the environmental impacts of BIOCORE products revealed that biorefineries based on the BIOCORE concept could have various potential impacts, ranging from significant environmental benefits to distinctly harmful outcomes. The drivers behind these impacts include factors such as the choice of product portfolio, the mode of implementation and external influences. In many cases the impact analysis revealed significant opportunities to optimize the biorefinery’s environmental performance. However, to correctly identify these the specific interdependencies of local factors will have to be taken into consideration, which will only be possible during the planning of an actual industrial biorefinery. Overall, in terms of environmental sustainability, BIOCORE has shown that its biorefinery concept has the potential to deliver environmental benefits and that these could, in specific circumstances, be greater than those offered by current biomass-based energy processes.
The project’s economic assessment of the bioerfinery concept was complicated by the current immaturity of the biorefinery sector, by market factors such as green premiums and by the fact that BIOCORE biorefineries are expected to co-manufacture several products aimed at markets with very different volumes and revenue structures. Nevertheless, clear indications were received that a biorefinery producing chemicals will be more profitable than an ethanol biorefinery and that certain products could benefit from significant green premiums. Finally, the economic analysis provided compelling arguments in favour of a new subsidy policy for bio-based products, which would provide subsidies for bio-based chemicals.
The researchers developed and tested several methods to study the social impacts of biorefining, making it possible to investigate a large number of social issues. Overall, these methods revealed that BIOCORE biorefineries could create new jobs and generate rural development. Competition for biomass was identified as a potential threat, which might be partly mitigated through close collaboration with local stakeholders, in particular farmers/forest owners. The project’s final report notes in particular the importance of conducting a thorough social impact assessment for any planned biorefinery based on the BIOCORE concept, which should take into account potential impacts along the entire value chain.
There are a number of pilot lignocellulose biorefineries currently operating – for example, in Denmark, Italy, Spain and Sweden. However, these are mainly focussed on fuel ethanol production and significant work is required to fully integrate the use of all biomass fractions in the manufacture of additional products. Consequently, there is clearly a need for industrial demonstration of new technologies that use lignocellulose as a raw material for the manufacture of both fuels and chemicals. By providing this, BIOCORE has made a significant contribution to the advancement of this technology and increased the potential for the use of bio-based products in the chemical industry in Europe.
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1 Species selected for adaptability to various climate and soil conditions, relative insusceptibility to pests and diseases, ease of propagation and speed of vegetative growth.