WoodCircus, Underpinning the vital role of the forest-based sector in the Circular Bioeconomy. D2.2 Resource Efficiency, Side Streams and Value Chain Analysis – WP2 Final Report

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An Overview of Thermal Treatment Emissions with a Particular Focus on CO2 Parameter

Waste-to-energy (WtE) technologies can offer sustainable solutions for waste that cannot be further reused or recycled, such as the part of municipal solid waste (MSW) that is not suitable for recycling processes. The two main (most widely used) thermal treatment technologies that can be applied to MSW are direct combustion in an incineration plant and gasification. This paper examines in particular the direct combustion in incineration plants, explaining the main process, the main technologies applied, and the resulting environmental aspects. Moreover, this work focuses on analyzing flue gas emissions from thermal treatment in order to better understand the impacts of these kinds of processes. A particular focus on the CO2 parameter is performed. CO2 is a persistent atmospheric gas, and it is one of the greenhouse gases (GHGs) potentially responsible for the climate change phenomenon. In this sense, specific indexes (tCO2/tMSW and tCO2/MWh) are elaborated considering the thermal treatment plants present in six Italian regions. The main aim of this review paper is to try to fill the gap that still exists regarding the emissions environmental compatibility coming from these type of plants, the evaluation of the amount of CO2 emitted, and the possible reduction of the CO2 parameter. One of the main outcome obtained is in fact the evaluation of the amount of CO2 coming from these kinds of plants and some indications about the technological possibilities of reducing this amount

MSW management in two italian mountainous areas

Two case studies are reported in the present work. They regard municipal solid waste (MSW) management trends in the last decades in two Italian provinces selected to analyse some issues of waste management in mountainous areas. The first case study refers to a selective collection (SC) rate expected to reach 80 % soon. This scenario assumes SC mainly in kerbside mode. The scenario is based on specific local conditions: the absence of a thermo-chemical plant in the territory (but with a part of the residual MSW burnt in a neighbour province), the presence of local plant of anaerobic, and a sanitary landfill for pre-treated residual MSW. The adopted tariff helped increasing the SC rate: indeed, since 2013, a tariff calculated at user level, depending on the behaviour of each user, has been adopted. This is called punctual tariff. The second case study concerns an area where SC reached about 75 %. The punctual tariff has been recently introduced. In this scenario, an incineration plant and a Solid Recovered Fuel (SRF) plant allow implementing an industrial symbiosis solution in conjunction with a cement factory. The work demonstrates that SC can be the core of a correct MSW management and that kerbside collection is fully compatible with mountainous area. However, other issues remain to be optimized yet: the low density of mountain areas makes difficult to implement enhanced solutions of SC (e.g. for diapers) and increases costs for light packaging collection; moreover, the presence of tourist fluxes can significantly affect SC efficiency

ENHANCING SUSTAINABLE PROCESS DESIGNS THROUGH STRATEGIC MATERIAL UTILIZATION AND WASTE MINIMIZATION APPROACHES

Sustainability is a growing concern as resources are continually depleted for various applications without adequate renewal plans. The resulting impacts on the ecosystem, health, and resource circularity are often overlooked. This research analyzes improvement opportunities at each major stage in a product\u27s life cycle. Raw material acquisition, product synthesis, process waste management, and the fate of a material in the end-of-life phases were examined. The viability of utilizing renewable resources has been demonstrated in this work by extracting bio-based chemicals from underutilized renewable resources at a commercial scale and transforming the extracted resources into polymeric materials. The optimization of raw material acquisition and process waste management have been accomplished via a superstructure-based approach that is modeled as MINLP optimization problem. Even though process sustainability can be achieved with strategic usage of renewable resources and recovery, the fate of post-consumer materials also poses major concerns regarding releases and emissions if left unmitigated. The guidelines surrounding the manufacturing and end-of-life phases of a material introduced in this work, backed by experimental and computational findings, can be used to effectively design environmentally conscious processes, inventions, and materials without sacrificing costs

Decision support strategies for the efficient implementation of circular economy principles in process systems

Economic growth at any expense is no longer an option. Awareness of the growing human footprint is crucial to face the problems that the impoverishment of ecosystems is causing and will cause in the future. One of the key challenges to address it is moving toward approaches to manage resources in a more sustainable way. In this light, circular economy stands as a promising strategy to improve the lifetime of resources by closing material and energy loops. The Process Systems Engineering (PSE) community has been developing methods and tools for increasing efficiency in process systems since the late 1980s. These methods and tools allow the development of more sustainable products, processes, and supply chains. However, applying these tools to circular economy requires special considerations when evaluating the introduction of waste-to-resource technologies. This Thesis aims at providing a set of models and tools to support in the decision-making process of closing material cycles in process systems through the implementation of waste-to-resource technologies from the circular economy perspective. The first part provides an overview of approaches to sustainability, presents the optimization challenges that circular economy and industrial symbiosis pose to PSE, and introduces the methodological and industrial scope of the Thesis. Part two aims at assessing the environmental and economic reward that may be attained through the application of circular economy principles in the chemical industry. With this purpose, a systematic procedure based on Life Cycle Assessment (LCA), economic performance and Technology Readiness Level (TRL) is proposed to characterize technologies and facilitate the comparison of traditional and novel technologies. The third part describes groundwork tasks for optimization models. A methodology is presented for the systematic generation of a list of potential waste-to-resource technologies based on an ontological framework to structure the information. In addition, this part also presents a targeting approach developed to include waste transformation and resource outsourcing, so a new dimension of potential destinations for waste are explored for the extension of material recovery. Finally, part four includes the development of decision-making models at the strategic and tactical hierarchical levels. At the network level, a framework is presented for the screening of waste-to-resource technologies in the design of process networks. The most promising processing network for waste recovery is identified by selecting the most favorable waste transformation processes among a list of potential alternatives. After the network selection, an optimization model is built for the detailed synthesis of individual processes selected in the resulting network. The developed methodologies have been validated and illustrated through their application to a case study under different viewpoints in the process industry, in particular to the chemical recycling of plastic waste. Despite the low Technology Readiness Level of some chemical recycling technologies, the results of this Thesis reveal pyrolysis as a promising technology to close the loop in the polymer sector. Overall, all these positive outcomes prove the advantages of developing tools to systematically integrate waste-to-resource processes into the life cycle of materials. The adaptation to this change of perspective of the well-established methods developed by the PSE community offers a wide range of opportunities to foster circular economy and industrial symbiosis. This Thesis aims to be a step forward towards a future with more economically efficient and environmentally friendly life cycles of materials.El crecimiento económico a cualquier precio ha dejado de ser una opción viable. Tener conciencia sobre nuestra creciente huella ambiental es clave para afrontar los problemas que el empobrecimiento de los ecosistemas está causando y causará en el futuro. Uno de los desafíos clave para abordarlo es avanzar hacia técnicas que permitan una gestión de recursos más sostenible. En esta línea, la economía circular es una estrategia con gran potencial para mejorar la vida útil de los recursos mediante el cierre de ciclos de materiales y energía. Desde finales de los años ochenta, la investigación en Ingeniería de Procesos y Sistemas (PSE) ha permitido generar métodos y herramientas para el desarrollo sostenible de productos, procesos y cadenas de suministro. Sin embargo, su aplicación en economía circular requiere consideraciones especiales al evaluar la introducción de nuevas tecnologías para el reciclaje de materiales. Esta Tesis tiene como objetivo proporcionar un conjunto de modelos y herramientas para apoyar el proceso de toma de decisiones sobre el aprovechamiento de materiales a través de la lente de la economía circular mediante la implementación de tecnologías de conversión de residuos en recursos. La primera parte presenta una visión general de los enfoques de sostenibilidad, lista los desafíos que la economía circular y la simbiosis industrial plantean en PSE, e introduce el alcance metodológico e industrial de la Tesis. La segunda parte tiene como objetivo evaluar los beneficios ambientales y económicos que se pueden obtener mediante la aplicación de los principios de la economía circular en la industria química. Con este propósito, se desarrolla un método sistemático basado en el análisis del ciclo de vida, el rendimiento económico y el nivel de madurez tecnológica para caracterizar las tecnologías de recuperación y facilitar la comparación entre técnicas tradicionales y en desarrollo. La tercera parte describe las tareas previas al desarrollo de los modelos de optimización. Se presenta una metodología para la generación sistemática de una lista de posibles tecnologías de conversión de residuos en recursos utilizando en un marco ontológico para estructurar la información. Además, se expone un método para acotar la transformación de residuos y la externalización de recursos, que permite explorar una nueva dimensión de destinos potenciales para los residuos, extendiendo así el grado de recuperación de materiales. Por último, la cuarta parte incluye el desarrollo de modelos de toma de decisiones a nivel estratégico y táctico. A nivel estratégico, se presenta un marco para la detección de tecnologías de reciclaje de residuos en el diseño de redes de procesos. Tras sintetizar la red, a nivel táctico se construye un modelo de optimización para el diseño detallado de los procesos individuales seleccionados en el mismo. Las metodologías desarrolladas han sido ilustradas y validadas a través de su aplicación en un caso de estudio con diferentes perspectivas sobre el reciclaje químico de residuos plásticos. A pesar del bajo nivel de madurez tecnológica de los procesos de reciclaje químico, los resultados de esta Tesis permiten identificar el gran potencial económico y ambiental de la pirolisis de residuos plásticos para cerrar su ciclo de materiales. En conjunto, los resultados demuestran las ventajas de desarrollar herramientas para integrar sistemáticamente los procesos de reciclaje de residuos en el ciclo de vida de los materiales. La adaptación a las necesidades de este cambio de perspectiva de métodos bien establecidos en la comunidad PSE ofrece grandes oportunidades para fomentar la economía circular y la simbiosis industrial. Esta tesis pretende ser un paso adelante hacia un futuro con ciclos de vida de materiales económica y ambientalmente más eficientes

Environmental Impacts of Electricity from Incineration and Gasification: How the LCA Approach Can Affect the Results

Waste-to-energy (WtE) technologies can offer sustainable solutions for waste, which can no more be reused or recycled, such as the part of municipal solid waste (MSW) that is not suitable for recycling processes. This study focused on the environmental consequences of the production of electricity from incineration and gasification of MSW. To this aim, the standardised life cycle assessment (LCA) methodology was used. A life cycle inventory, mainly composed by primary data, is provided. Starting from these data, different highly shared LCA approaches were used to calculate the potential impacts of 1 kWh provided by the two analysed WtE technologies. The different approaches concern the method of accounting for the by-products (through an economic allocation and a system expansion) and the inclusion/exclusion of environmental benefits due to the avoided landfill for the MSW. For each approach, impact-assessment results were calculated with the ReCiPe midpoint (H) method. A comparison was carried out (i) between the results obtained for the same WtE technology but calculated with different approaches and (ii) between the impact results of electricity generated by the two WtE technologies calculated with the same approach. From the study, it emerged that, according to the accounting rules, the impact results can significantly change and, for some impact categories, even lead to opposite conclusions. In the absence of category rules that harmonise the environmental assessments of WtE processes, it is therefore recommended that the development/use/reproduction/comparison of studies focused on the valorisation of waste should be carried out with caution

Mitigation of Methane Emissions: A Rapid and Cost-Effective Response to Climate Change

Methane is a major anthropogenic greenhouse gas, second only to carbon dioxide (CO2) in its impact on climate change. Methane (CH4) has a high global warming potential that is 25 times as large as the one of CO2 on a 100 year time horizon according to the latest IPCC report. Thus, CH4 contributes significantly to anthropogenic radiative forcing, although it has a relatively short atmospheric perturbation lifetime of 12 years. CH4 has a variety of sources that can be small, geographically dispersed, and not related to energy sectors. In this report, we analyze methane emission abatement options in five different sectors and identify economic mitigation potentials for different CO2 prices. While mitigation potentials are generally large, there are substantial potentials at low marginal abatement costs. Drawing on different assumptions on the social costs of carbon, we calculate benefit/cost ratios for different sectors and mitigation levels. We recommend an economically efficient global methane mitigation portfolio for the year 2020 that includes the sectors of livestock and manure, rice management, solid waste, coal mine methane and natural gas. Depending on assumptions of social costs of carbon, this portfolio leads to global CH4 mitigation levels of 1.5 or 1.9 GtCO2-eq at overall costs of around $14 billion or$30 billion and benefit/cost ratios of 1.4 and 3.0, respectively. We also develop an economically less efficient alternative portfolio that excludes cost-effective agricultural mitigation options. It leads to comparable abatement levels, but has higher costs and lower benefit/cost ratios. If the global community wanted to spend an even larger amount of money - say, $250 billion - on methane mitigation, much larger mitigation potentials could be realized, even such with very high marginal abatement costs. Nonetheless, this approach would be economically inefficient. If the global community wanted to spend such an amount, we recommend spreading the effort cost-effectively over different greenhouse gases. While methane mitigation alone will not suffice to solve the climate problem, it is a vital part of a cost-effective climate policy. Due to the short atmospheric lifetime, CH4 emission reductions have a rapid effect. Methane mitigation is indispensable for realizing ambitious emission scenarios like IPCC's "B1", which leads to a global temperature increase of less than 2°C by the year 2100. Policy makers should put more emphasis on methane mitigation and aim for realizing low-cost methane mitigation potentials by providing information to all relevant actors and by developing appropriate regulatory and market frameworks. We also recommend including methane in emissions trading schemes.Methane, mitigation, climate change, cost-benefit analysis

A life cycle optimization framework for the sustainable design of circular municipal solid waste management systems

RESUMEN: Los objetivos de esta tesis son desarrollar un marco metodológico para determinar la configuración óptima de los sistemas integrados de gestión de residuos bajo una perspectiva del ciclo de vida, e investigar si la economía circular contribuye a la reducción del consumo de recursos y los impactos ambientales y al crecimiento económico. El marco metodológico propuesto se aplicó a la gestión de residuos municipales orgánicos en la Comunidad Autónoma de Cantabria. El modelo del sistema se construyó combinando análisis de flujo de materiales y análisis de ciclo de vida (ambiental y económico). Se formuló un problema de optimización multi-objetivo para maximizar la circularidad de los nutrientes y minimizar el uso de recursos, los impactos ambientales y los costes de gestión de residuos. Los resultados sugieren que mejorar la circularidad de los recursos no implica necesariamente una reducción de costes, del consumo de recursos o de la emisión de cargas ambientales.ABSTRACT: The objectives of this dissertation are twofold: to develop a methodological framework to select the optimal configuration of integrated waste management systems under a life cycle perspective, and to investigate whether adopting a circular economy is an effective measure to attain increased economic benefits and a reduction in resource consumption and environmental impacts. The proposed framework – based the expansion of the boundaries of linear waste management systems – was applied to the management of municipal organic waste in the Spanish region of Cantabria. The system model was constructed combining material flow analysis, life cycle assessment and life cycle costing tools. A multi-objective optimization problem was formulated to maximize nutrient circularity and minimize resource use, environmental impacts and waste management costs. The results suggest that improving resource circularity can lead to increased costs and does not necessarily entail a decrease in the consumption of natural resources or the emission of environmental burdens.The author has been the recipient of two predoctoral fellowships granted by the University of Cantabria and the Spanish Ministry of Education (code FPU 15/01771). Her visit to NCSU was funded by a predoctoral mobility scholarship awarded by the University of Cantabria and by the research project CTQ2016-76231-C2-1-R, whereas her research at Cornell University was sponsored by the FPU program (code EST18/00007). She gratefully acknowledges this financial support

OPTIMIZATION OF wasteWOIMA’s MODULAR POWER PLANT INSTALLATION USING 3D SIMULATION AND VIRTUAL REALITY

The primary objective of this research is to optimize module installation procedure for Woima’s modular WTE power plant by making a Three-Dimensional (3D) simulation of the power plant and inspecting the model using Virtual Reality (VR). This thesis ad-dresses the research question on how to use 3D simulation to reduce time and cost dur-ing the construction. Therefore, this thesis suggests an installation procedure where each module fits into the other as it were a lego puzzle. This proposed building procedure is previewed as 3D simulation that could then be used to optimize the construction of wasteWOIMA’s modular power plant. This research work employs the use of primary data, CAD blueprints, sourced from the case company, while secondary data was sourced from books, online repository, aca-demic and scientific journals. To uphold the credibility of this research, it utilized both experimental and case study research strategies to conceptualize the simulation of the power plant which can be previewed on Virtual Reality (VR) glasses. VR model inspec-tion provides an immersive and real-life scale experience. The entire 3D simulation was done using SketchUp software, a 3D modelling and simulation tool. A VR session was also carried out during the research to help identify areas of possible improvement with safety, cost and quality, using HTC Vive VR glasses and Symmetry Alpha software. The outcome of this research shows that 3D simulation, especially when combined with VR models inspection, can help to optimize models to prevent errors during actual con-struction work, hence, saving cost and reducing lead time

Editorial: SDEWES science - The path to a sustainable carbon neutral world

In 2021, the 16th SDEWES (Sustainable Development of Energy, Water and Environment Systems) Conference was held in Dubrovnik (Croatia), October 10th – 15th and delivered more than 690 contributions, presented in regular and 13 special sessions, with 7 invited lectures devoted to various sustainability topics. The Energy journal has continued its cooperation with SDEWES launching a special issue dedicated to this SDEWES Conference. The 29 selected papers cover a wide variety of issues in the fields of energy, water and environment, and all of them propose novel approaches or remarkable advances in well established research lines already explored in past SDEWES Conferences