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System Integration in the Energy Transition

Lectorale redeboekje naar aanleiding van de intrede in het lectoraat Systeemintegratie in de energietransitie

Improving the sustainability of farming practices through the use of a symbiotic approach for anaerobic digestion and digestate processing

The dairy sector in the Netherlands aims for a 30% increase in efficiency and 30% carbon dioxide emission reduction compared to the reference year of 1990, and a 20% share of renewable energy, all by the year 2020. Anaerobic Digestion (AD) can play a substantial role in achieving these aims. However, results from this study indicate that the AD system is not fully optimized in combination with farming practices regarding sustainability. Therefore, the Industrial Symbiosis concept, combined with energy and environmental system analysis, Life Cycle Analysis and modeling is used to optimize a farm-scale AD system on four indicators of sustainability (i.e., energy efficiency, carbon footprint, environmental impacts and costs). Implemented in a theoretical case, where a cooperation of farms share biomass feedstocks, a symbiotic AD system can significantly lower external energy consumption by 72 to 92%, carbon footprint by 71 to 91%, environmental impacts by 68 to 89%, and yearly expenditures by 56 to 66% compared to a reference cooperation. The largest reductions and economic gains can be achieved when a surplus of manure is available for upgrading into organic fertilizer to replace fossil fertilizers. Applying the aforementioned symbiotic concept to the Dutch farming sector can help to achieve the stated goals indicated by the Dutch agricultural sector for the year 2020.

3D Printing with biomaterials

Het boek ‘3D Printing with biomaterials’ introduceert een manier om een duurzame en circulaire economie te realiseren; 3D printen gecombineerd met het gebruik van biomaterialen.

Green-washing or best case practices?

Closed loop or ‘circular’ production systems known as Circular Economy and Cradle to Cradle represent a unique opportunity to radically revise the currently wasteful system of production. One of the challenges of such systems is that circular products need to be both produced locally with minimum environmental footprint and simultaneously satisfy demand of global consumers. This article presents a literature review that describes the application of circular methodologies to education for sustainability, which has been slow to adopt circular systems to the curriculum. This article discusses how Bachelor and Master-level students apply their understanding of these frameworks to corporate case studies. Two assignment-related case studies are summarized, both of which analyze products that claim to be 'circular'. The students' research shows that the first case, which describes the impact of a hybrid material soda bottle, does not meet circularity criteria. The second case study, which describes products and applications of a mushroom-based material, is more sustainable. However, the students' research shows that the manufacturers have omitted transport from the environmental impact assessment and therefore the mushroom materials may not be as sustainable as the manufacturers claim. As these particular examples showed students how green advertising can be misleading, applying “ideal” circularity principles as part of experiential learning could strengthen the curriculum. Additionally, this article recommends that sustainable business curriculum should also focus on de-growth and steady-state economy, with these radical alternatives to production becoming a central focus of education of responsible citizens. https://doi.org/10.1016/j.jclepro.2019.02.005 LinkedIn: https://www.linkedin.com/in/helenkopnina/

Conversion of a Xylose-rich Stream from Biomass-biorefining into Polyhydroxyalkanoate (PHA) by Schlegelella thermodepolymerans

The transition to a biobased economy necessitates utilizing renewable resources as a sustainable alternative to traditional fossil fuels. Bioconversion is a way to produce many green chemicals from renewables, e.g., biopolymers like PHAs. However, fermentation and bioconversion processes mostly rely on expensive, and highly refined pure substrates. The utilization of crude fractions from biorefineries, especially herbaceous lignocellulosic feedstocks, could significantly reduce costs. This presentation shows the microbial production of PHA from such a crude stream by a wild-type thermophilic bacterium Schlegelella thermodepolymerans [1]. Specifically, it uses crude xylose-rich fractions derived from a newly developed biorefinery process for grassy biomasses (the ALACEN process). This new stepwise mild flow-through biorefinery approach for grassy lignocellulosic biomass allows the production of various fractions: a fraction containing esterified aromatics, a monomeric xylose-rich stream, a glucose fraction, and a native-like lignin residue [2]. The crude xylose-rich fraction was free of fermentation-inhibiting compounds meaning that the bacterium S.thermodepolymerans could effectively use it for the production of one type of PHA, polyhydroxybutyrate. Almost 90% of the xylose in the refined wheat straw fraction was metabolized with simultaneous production of PHA, matching 90% of the PHA production per gram of sugars, comparable to PHA yields from commercially available xylose. In addition to xylose, S. thermodepolymerans converted oligosaccharides with a xylose backbone (xylans) into fermentable xylose, and subsequently utilized the xylose as a source for PHA production. Since the xylose-rich hydrolysates from the ALACEN process also contain some oligomeric xylose and minor hemicellulose-derived sugars, optimal valorization of the C5-fractions derived from the refinery process can be obtained using S. thermodepolymerans. This opens the way for further exploration of PHA production from C5-fractions out of a variety of herbaceous lignocellulosic biomasses using the ALACEN process combined with S. thermodepolymerans. Overall, the innovative utilization of renewable resources in fermentation technology, as shown herein, makes a solid contribution to the transition to a biobased economy.[1] W. Zhou, D.I. Colpa, H. Permentier, R.A. Offringa, L. Rohrbach, G.J.W. Euverink, J. Krooneman. Insight into polyhydroxyalkanoate (PHA) production from xylose and extracellular PHA degradation by a thermophilic Schlegelella thermodepolymerans. Resources, Conservation and Recycling 194 (2023) 107006, ISSN 0921-3449, https://doi.org/10.1016/j.resconrec.2023.107006. [2] S. Bertran-Llorens, W.Zhou. M.A.Palazzo, D.I.Colpa, G.J.W.Euverink, J.Krooneman, P.J.Deuss. ALACEN: a holistic herbaceous biomass fractionation process attaining a xylose-rich stream for direct microbial conversion to bioplastics. Submitted 2023.

Applying principles of circular economy to sustainable tourism.