• Energy Research

The power plant sector is adopting the co-firing of biomass and solid recovered fuel (SRF) with coal in an effort to reduce its environmental impact and costs. Whereas this intervention contributes to reducing carbon emissions and those of other pollutants related with the burning of fossil fuel, it may also result in hidden impacts that are often overlooked. When co-firing, the physical and chemical properties of the mixed fuels and the subsequent technical implications on the process performance and by-products are significant. Interconnections between multiple values nested within four domains of value, i.e. environmental, economic, technical and social, mean that changes in the one domain (in the co-firing case, the technical one) can have considerable implications in the other domains as well. In this study, using a systematic and flexible approach to conceptualising multi-dimensional aspects associated with the co-firing of biomass and SRF with coal, we unveil examples of such interconnections and implications on overall value delivered through the use and recovery of waste resources. Such an analysis could underpin the selection of useful metrics (quantitative or semi-quantitative descriptors) for enabling a systemic multi-dimensional value assessment, and value's distribution amongst interconnected parts of resource recovery systems; key in enabling sound analysis and decision-making.

The influence of IrO2 loading on the effectiveness factor Et of the electrochemical oxidation of isopropanol was investigated A model has been proposed based on three main reactions electrochemical IrO2 oxidation to IrO3 chemical oxidation of the organic compound via IrO3 and O-2 evolution via decomposition of IrO3 It has been found that the relative effectiveness factor E-f for the electrochemical oxidation of IrO2 to IrO3 is loading independent contrary to the chemical reaction which decreases with increasing IrO2 loading (C) 2010 Elsevier Ltd All rights reserved

While attention on the importance of closing materials loops for achieving circular economy (CE) is raging, the technicalities of doing so are often neglected or difficult to overcome. These technicalities determine the ability of materials, components and products (MCPs) to be properly recovered and redistributed for reuse, recycling or recovery, given their remaining functionality, described here as the remaining properties and characteristics of MCPs. The different properties of MCPs make them useful for various functions and purposes. A transition, therefore, towards a CE would require the utmost exploitation of the remaining functionality of MCPs; ideally, enabling recirculation of them back in the economy. At present, this is difficult to succeed. This short communication article explains how the remaining functionality of MCPs, defined here as quality, is perceived at different stages of the supply chain, focusing specifically on plastic packaging, and how this affects their potential recycling. It then outlines the opportunities and constraints posed by some of the interventions that are currently introduced into the plastic packaging system, aimed at improving plastic materials circularity. Finally, the article underpins the need for research that integrates systemic thinking, with technological innovations and policy reforms at all stages of the supply chain, to promote sustainable practices become established.

Plastic is a commodity that supports our modern lifestyles. Its remarkable range of properties (e.g., durability, lightweight, good barrier properties) combined with the ease of processing make plastic a sustainable alternative over other materials (e.g., glass, metals, and paper), of which production, use, and management can be more resource intensive. Owing to these attributes, plastics are considered to have an important role to play in promoting sustainability as part of a circular economy (CE). CE is a concept that seeks to promote a sustainable way of living, where resources are used more efficiently and are retained in the economy for as long as possible. The latter can be achieved by creating loops that feed resources back into the system for use in same or new components and products with the same or lower functionality. Paradoxically, plastics present also one of the biggest challenges to achieving a CE. This is because, in spite of their great potential to promote resource efficiency upstream, i.e., at the production stage, a vast amount of the plastic that becomes waste escapes into the environment and/or is largely mismanaged at the consumption and management stage. This highlights the urgent need for scrutiny in the way plastics are designed, produced, used, and managed, to better understand how to improve their ability to circulate back into the system, recovering maximum value from them. In this chapter, we present a framework for plastic waste management placing emphasis on their circularity potential via existing processes. Given the rapid emergence of bioplastics in the plastic industry, it would be an omission not to discuss their opportunities and implications in promoting circularity. Consideration of all aspects in the plastic and plastic waste system and of the processes that go beyond end-of-pipe solutions highlights that sustainable management necessitates a combination of an integrated solid waste management strategy with a renewed focus on designing out plastic waste. Scopus

Sustainability assessment of resource recovery from waste is an important prerequisite for informed and sound decision-making. Life Cycle Sustainability Assessment (LCSA) has been developed to support this process, yet its use is still constrained by the difficulty of identifying the most relevant impact parameters. This paper, seeks to inform LCSA for resource recovery from waste based on a parameter identification approach that uses the political, economic, social, technological, environmental and legal (PESTEL) analysis. The novelty of this approach lies in the structured conceptualisation of the resource recovery system and the context within which decisions are made. The anaerobic digestion of source-separated food waste in the UK is used as a case study to trial and demonstrate the approach. Findings suggest that a conceptual, qualitative analysis, although limited in its scope due to the lack of quantitative components, is suitable in integrating different parameters, allowing for a holistic conceptualisation of the system and capturing important issues that could be easily overlooked. This type of analysis can summarise the key interdependencies, contrast the trade-offs and provide a wider understanding of the political and legal context within which the system operates, all important in extending the implementation of LCSA towards the right direction.

Around 6 million tonnes of edible food are being wasted (post-farm gate) in the UK each year. This fraction of edible wasted food is known as avoidable food waste. In a circular economy food is a valuable resource that must be captured at all stages of the food supply chain and, where possible, redistributed for consumption. This can prevent avoidable food waste generation, and dissipation of food’s multidimensional value that spans environmental, economic, social, technical and political/organisational impacts. While the importance and benefits of surplus food redistribution have been well documented in the global literature, there are still barriers that prevent perfectly edible food from being wasted. This study looks at the main stages of the food supply chain, and amasses the opportunities, challenges and trade-offs associated with surplus food redistribution to the UK economy. It highlights points in the food system where interventions can be made, to improve food’s circularity and sustainability potential. Stakeholder interrelations, regulatory and socio-economic aspects are discussed in relation to their influence on decreasing avoidable food waste. The main output from this work is a diagrammatic depiction of where challenges and trade-offs occur along the food supply chain, and how policy and socio-economic reforms are needed to maximise avoidable food waste prevention, and the surplus avoidable food redistribution in the food supply chain for social benefit.