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• Different configurations were tested for producing biogas from roadside grass. • Dry digestion succeeded at pilot and large scale, but the latter can be improved. • Digested fibers performed better than undigested fibers for biomaterial production. • Anaerobic digestion might be stopped midway for improved fiber recovery. • Market potential of roadside grass for biomaterials production was significant. Roadside grass clippings hold potential as a sustainable source of bioenergy as they do not compete with crops for land use, and are only partially utilized for low-value applications. In this study, we proposed using roadside grass as a sole feedstock for anaerobic digestion (AD) in three different settings, and assessed the potential of producing biomaterials and fertilizers from grass-based digestate. Wet continuous digestion at pilot scale and dry batch digestion at pilot and large scales resulted in biogas yields up to 700 Nm3.t−1 DOM with a methane content of 49–55 %. Despite promising results, wet AD had operational problems such as clogging and poor mixing; once upscaled, the dry digestion initially also presented an operational problem with acidification, which was overcome by the second trial. Digested grass fibers from the pilot dry AD were processed into biomaterials and performed similarly or better than the undigested fibers, while around 20 % performance reduction was observed when compared to reference wood fibers. A mass balance indicated reduced fiber recovery when higher biogas production was obtained. The liquid fraction from the pilot dry AD was characterized for its nutrient content and used as a biofertilizer in another study. In contrast, the leachate collected from the large-scale dry AD had a low nitrogen content and high chloride content that could hinder its further use. Finally, a regional market analysis was conducted showing that the biocomposites produced with the available grass fibers could substitute at least half of the current European market based on our results. [ABSTRACT FROM AUTHOR]

A future bio-based economy envisions the transformation of the petrochemical industry into using biomass such as wood (waste) as a major resource. The early-stage evaluation of a biorefinery project requires the optimization of the lay-out of the supply chain considering the spatio-temporal variability of the availability of feedstock and the techno-economical characteristics of the biorefinery process. Therefore, the presented methodology was developed combining three models: (1) a forest management and planning tool providing a detailed prediction on the wood resource availability as well as the harvested feedstock quantity and cost with respect to location and time, (2) a techno-economic assessment model of the biorefinery process (e.g., species-specific conditions, capacity, CAPEX, OPEX), and (3) a strategic supply chain optimization model combining the insights of (1) and (2) into a spatio-temporal explicit supply chain analysis. The developed methodology has been evaluated through a case-study on the emerging reductive catalytic fractionation (RCF) biorefining in the Flanders region (EU) and shows that the most economically interesting configuration is one large biorefinery with a yearly wood chip intake of 150 kton. The biorefinery location reflects the available feedstock distribution in Flanders and is suggested to be situated best in the most forested region. The proposed methodology proved to be dynamic and robust: (1) input data and technical calculations can easily be adapted or updated; (2) the methodology can be applied to a broad range of applications beyond the scope of the biorefinery, to different feedstock choices; (3) the impact of the biorefinery location on e.g. energy balance, CO 2 emissions, and financial balance can be assessed. [Display omitted] • Integration of resource availability, techno-economic analysis, supply chain design. • Supports designing new bio-based value chains at low Technology Readiness Level. • Case study on emerging reductive catalytic fractionation in Flanders. • Region features and time variations impact process feasibility and chain layout. [ABSTRACT FROM AUTHOR]

Abstract: Biomass as a renewable energy source has many advantages and is therefore recognized as one of the main renewable energy sources to be deployed in order to attain the target of 20% renewable energy use of final energy consumption by 2020 in Europe. In this paper the concept of a biomass Energy Conversion Park (ECP) is introduced. A biomass ECP can be defined as a synergetic, multi-dimensional biomass conversion site with a highly integrated set of conversion technologies in which a multitude of regionally available biomass (residue) sources are converted into energy and materials. A techno-economic assessment is performed on a case study in the Netherlands to illustrate the concept and to comparatively assess the highly integrated system with two mono-dimensional models. The three evaluated models consist of (1) digestion of the organic fraction of municipal solid waste, (2) co-digestion of manure and co-substrates, and (3) integration. From a socio-economic point of view it can be concluded that it is economically and energetically more interesting to invest in the integrated model than in two separate models. The integration is economically feasible and environmental benefits can be realized. For example, the integrated model allows the implementation of a co-digester. Unmanaged manure would otherwise represent a constant pollution risk. However, from an investor’s standpoint one should firstly invest in the municipal solid waste digester since the net present value (NPV) of this mono-dimensional model is higher than that of the multi-dimensional model. A sensitivity analysis is performed to identify the most influencing parameters. Our results are of interest for companies involved in the conversion of biomass. The conclusions are useful for policy makers when deciding on policy instruments concerning manure processing or biogas production. [Copyright &y& Elsevier]

Abstract: European policy states that by 2020 at least 20% of final energy consumption should come from renewable energy sources. Biomass as a renewable energy source cannot be disregarded in order to attain this target. In this study a macro screening approach is developed to determine potential locations for biomass valorization in a specified region. The approach consists of five steps: (1) criteria determination, (2) data gathering, (3) weight assignment, (4) final score, (5) spatial representation. The resulting outcome provides a first well balanced scan of the possibilities for energy production using regional biomass. This way policy makers and investors can be supported and motivated to study the possibilities of building energy production plants at specific locations in more detail, which can be described as a ‘micro-screening’. In our case study the approach is applied to determine the potentially interesting locations to establish a biomass project. The region has been limited to the forty-four communities in the province of Limburg (Belgium). The macro screening approach has shown to be very effective since the amount of interesting locations has been reduced drastically. [Copyright &y& Elsevier]