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Asphaltenes, the heaviest and most polar components of crudes, are generally associated with considerable operational issues in refineries. In order to understand potential operational issues during upgrading/processing of bio-crudes, structural and thermal behaviour of asphaltenes derived from bio-crude (bio-asphaltenes) from hydrothermal liquefaction of food-waste and wood residues were compared with petroleum derived asphaltenes derived from bitumen. Structural analysis using nuclear magnetic resonance and elemental analysis revealed 7 aromatic rings per unit structure for bitumen asphaltenes, 4 for food-waste asphaltenes, and 3 for wood asphaltenes. The calculated molecular weight per unit structure followed the order: bitumen asphaltenes (589–636 g mol−1) > food-waste derived asphaltenes (338–358 g mol−1)> wood residue derived asphaltenes (268–274 g mol−1). The carbon residues using thermal gravimetric analysis (bitumen asphaltenes = 40%, bio-asphaltenes = 19–25%) and glass transition temperature (bitumen asphaltenes = 80 °C, bio-asphaltenes = 4–64 °C) followed the same order. These results indicate a very different structural and thermal behaviour for petroleum and bio-asphaltenes.

The biodegradable portion of solid waste generated in farmhouses can be treated for energy recovery with small portable biogas plants. This action can be done across the Netherlands and all around the planet. This study aims to appraise the performance of anaerobic digestion of different wastes (cow manure, food waste and garden waste) obtained from a regional farmhouse. Batch reactors were established under mesophilic conditions in order to investigate the impact of ternary mixtures on the anaerobic digestion process performance. Different mixing ratios were set in the batch tests. The upshots from the experiments connoted that ternary digestion with cow manure:food waste:garden waste mixing ratio of 40:50:10 yielded higher biogas amount. The kinetics’ results showed quite good congruence with the experimental study. The results from the kinetic analysis appeared to be in line with the experimental one.

In this study, life cycle assessment has been used to evaluate life cycle environmental impacts of substituting traditional anaerobic digestion (AD) feedstocks with food wastes. The results have demonstrated the avoided GHG emissions from substituting traditional AD feedstocks with food waste (avoided GHG-eq emissions of 163.33 CO2-eq). Additionally, the analysis has included environmental benefits of avoided landfilling of food wastes and digestate use as a substitute for synthetic fertilisers. The analysis of the GHG mitigation benefits of resource management/circular economy policies, namely, the mandating of a ban on the landfilling of food wastes, has demonstrated the very substantial GHG emission reduction that can be achieved by these policy options – 2151.04 kg CO2 eq per MWh relative to UK Grid. In addition to the reduction in GHG emission, the utilization of food waste for AD instead of landfilling can manage the leakage of nutrients to water resources and eliminate eutrophication impacts which occur, typically as the result of field application. The results emphasise the benefits of using life-cycle thinking to underpin policy development and the implications for this are discussed with a particular focus on the analysis of policy development across the climate, renewable energy, resource management and bioeconomy nexus and recommendations made for future research priorities.

Biofuels production is expected to be an intrinsic confluence to the renewable energy sector in the coming years under the European regulations for renewable energy. Key standpoints of the biofuels promotions are the reduction of national carbon emissions and rural deployment. Despite jubilant outlook of biofuels for sustainable development, research efforts still tend to link the biofuel industry and regional growth. The aim of this study is to explore and review the biofuels industry through a socio-political, techno-economic, legal and environmental (PESTLE) analysis approach, and discuss the interrelation between technological facets and sustainable deployment.

The goal of this research was to appraise the effect of combined inoculation on the performance of anaerobic digesters treating hardly degradable material, and particularly the pressed fine sieved fraction (PFSF) derived from wastewater treatment plants (WWTPs). Batch tests were conducted in mesophilic conditions in order to examine the optimal mixing ratio of inoculums. Mixing ratios of 100:0, 75:25, 50:50, 25:75, and 0:100 of three different inoculums were applied in the batch tests. The findings indicated that the inoculation of digested activated sludge with digested organic fraction of municipal solid waste (MSW) in the ratio 25:75 resulted in a higher PFSF degradation and a higher biogas yield. The results from the kinetic analysis fit well with the results from the batch experiment.