This thesis develops quantitative methods for evaluation and design of large-scale biofuel production systems with a particular focus on bioreactor-based fuel systems. In Chapter 2, a lifecycle assessment (LCA) method is integrated with chemical process modeling to select from different process designs the one that maximizes the energy efficiency and minimizes the environmental impact of a production system. An algae-based ethanol production technology, which is in the process of commercialization, is used as a case study. Motivated by this case study, Chapter 3 studies the selection of process designs and production capacity of highly distributed bioreactor-based fuel system from an economic perspective. Nonlinear optimization models based on net present value maximization are developed that aim at selecting the optimal capacities of production equipment for both integrated and distributed-centralized process designs on symmetric production layouts. Global sensitivity analysis based on Monte Carlo estimates is performed to show the impact of different parameters on the optimal capacity decision and the corresponding net present value. Conditional Value at Risk optimization is used to compare the optimal capacity for a risk-neutral planner versus a risk-averse decision maker. Chapter 4 studies mobile distributed processing in biofuel industry as vehicle routing problem and production equipment location with an underlying pipeline network as facility location problem with a focus on general production costs. Formulations and algorithms are developed to explore how fixed cost and concavity in the production cost increases the theoretical complexity of these problems.

Products make substantial impact on environment. Design for Environment (DfE) is an approach to design where all the environmental impacts of a product are considered over entire products life. Since over 80% of the product costs are committed during the early stages, design can play a central role in reducing this environmental overloading by product. However, unlike cost and performance, use of environmental criteria and DfE is far from part of mainstream designing. Individual guidelines often exist for DfE but these are not integrated with design tools. There is a need for capture of the rationale in design process as a know how backup for later use. Life Cycle Assessment (LCA) is currently the most promising and scientifically proven technique for estimating environmental impacts of a product during its lifecycle. Current LCA tools are not well integrated with design process and CAD tools. Consequently, there is a need for an LCA tool integrated into the natural design process that can be applied to early as well as detailed design stages. Detailed LCA is critically dependent on high volumes of product specific data, time consuming, often unaffordable and used after the detailed stages of design. Current approximate LCA methods are either incomplete, inaccurate or require prior knowledge of what data is important There is substantial uncertainty involved in the environmental impact calculations in LC. While Literature discusses uncertainty of impact data, there is no discussion on how to calculate and represent the total uncertainty in the potential impact of a product proposal at any given stage in design with respect to LCA. There is a need for a method that can aid in decision making by supporting quantitative comparison of available alternatives to identify the best alternative, under uncertain information about alternatives. Often the likely performance, cost or environmental impacts of a product proposal could be estimated only with certain confidence, which may vary from one proposal to another. The overall objective of this thesis is to “Develop a support to the designers using which they can develop environmentally friendly product lifecycles in much the same way as they currently design products, at all stages of their design, while reusing information from their past design activities”. For this the specific objectives are to: 1.Understand how designers currently design products and what they need for developing environmentally friendly product design. 2.Develop a holistic framework for both generation and evaluation of environmentally friendly life cycle proposals. 3. Capture rationale as part of the design process. 4. Estimate uncertainty in the environmental impact assessment during design. 5. Evaluate product lifecycle proposals with multiple criteria under uncertainty. 6. Integrate design process with environmental impact assessment. 7. Apply environmental impact assessment through the design process. From the descriptive studies we found that there is substantial difference in the environmental impact among products having the same functionality generated during the same design process. Analysis of industrial products available in the market show similar results. This means that design can substantially affect the impact created by a product. In our studies, designers did not consider environmental impact as a criterion in evaluation and we also identified the typical activities performed by designers during An Interactive Support for Developing Environmentally Friendly Product Lifecycles designing that must be allowed, supported or taken into account while developing a support for environmentally friendly product lifecycle design (EFPLD). The requirements of the designer for support are: tools should be proactive, easy to learn, understand and use, allow understanding of design rationale, act as a checklist, reduce total time, store knowledge and experience as know‐how backup, useful in all stages of design, not require too much extra effort for analysis, integrated to CAD, aid in trade off between choices, show uncertainty analysis, aid in analysis & improvement, and consider all lifecycle phases. A holistic framework, ACLODS (is a acronym of the six dimensions) constituting the following six dimensions: a) Activities, b) Criteria, c) Lifecycle phases, d) Outcomes, e) Design stages, and f) Product Structure was proposed for development of environmentally friendly product lifecycle designs. Through descriptive studies we found mainly 4 categories and associated sub categories of uncertainty in information with respect to LCA in design. The four categories are uncertainty in product structure, lifecycle phases, data quality, and methodological choices. The sub categories are assemblies, sub- assemblies, parts, relations, and features in product structure, material, production, distribution, usage, and after‐usage in lifecycle phases, temporal relevance, spatial relevance and sample size in data quality, and temporal relevance, spatial relevance, and comprehensiveness in methodological choices. At any point of time, uncertainty in information available is an accrual of the combination of the individual uncertainties. A method called confidence weighted objectives method is developed to compare the whole lifecycle of product proposals using multiple evaluation criteria under various levels of uncertainty. It is compared with normal weighted objectives method and found to be better since it estimates the overall worth of proposal nd confidence on the estimate, enabling deferment of decision making when decisions cannot be made using current information available. A new integrated platform IDEA‐SUSTAIN is developed in this thesis for supporting synthesis in product development on a commercial CAD workspace, while also aiding automated capture and storage of the rationale behind the decisions for retrieval whenever required during design. It is extended to support life cycle assessment of product proposals created by automatically extracting the information already stored while designing and ask for other information required to model the lifecycle without much extra effort from the designer. Then it uses the method for uncertainty reasoning developed also as a part of this research to estimate the level of confidence on the impact value owing to the incompleteness in knowledge available. The estimation is possible at part, assembly or product levels, for a single lifecycle phase or multiple phases. Using in‐house design exercises and feedback questionnaire evaluation of support is done. The usage of Idea‐Sustain has been found to be the best for both generation and evaluation of product proposals. The two computer aided tools – software (LCA) and Idea-Sustain-are compared with each other for fulfilling the functional requirements by analysing the feedbacks given by the designers on these tools against these requirements. Idea‐Sustain fulfilled well most of the requirements while the software (LCA) fulfilled only some of the needs, that too less effectively.

Companies are increasingly pressed to consider sustainability aspects when making decisions during product development. However, the methodological support for doing so is immature. The immaturity is particularly pronounced regarding the social dimension (or pillar) of sustainability and regarding strategic sustainability considerations. The overall aim of this thesis was to explore how the social dimension of sustainability and a strategic sustainability perspective could be better included in methodological support for product development. This was pursued in two ways.   Firstly, a two-staged review of the literature was conducted. Stage one focused on summarizing the state of the art of integration of social sustainability aspects in product development and stage two focused on critically analyzing and evaluating these efforts. The Framework for Strategic Sustainable Development was used to guide the analysis of the current integration efforts and the evaluation of their potential for supporting sustainable product development and strategic sustainable development in general. Secondly, a recently published principled definition of social sustainability was used to enhance two approaches for including sustainability considerations in product development. One of these approaches is focused on decision-making support at concept selection, based on assessment and comparison of sustainability implications of the considered product concepts. The other approach is focused on developing sustainability criteria and a related sustainability compliance index in support of concept development.   In the literature review, social life cycle assessment methods (Social LCA) were found to represent a large part of the current efforts, and several challenges with those methods were identified. From a decision support perspective, they were found to have weaknesses regarding applicability and robustness: results from the assessment, usually performed by scientists to evaluate a scientific question, may be too complex to interpret from a business standpoint; the impact perspective may be too narrow, missing important aspects of social sustainability; and generally they lack a strategic perspective. The use of a strategic sustainable development perspective in the approaches prototyped in this thesis is a way of tackling these challenges. The use of backcasting from visions framed by sustainability principles can: help organize and make sense of the general field of sustainability, highlighting where overlaps between objectives exist; provide the long term perspective needed for sustainability; allow for product developers to gain awareness of potential impacts of a product’s life cycle phases within existing knowledge, time and resource constraints; help build a roadmap in order to reduce a product’s contribution to unsustainability (including social unsustainability).   Future research will focus on further testing and development of the suggested approaches and specifically on further development of tactical design guidelines that provide support for the fulfilment of long-term sustainability criteria and clarify the connection between decisions taken during product development and a product’s sustainability profile.

The building sector contributes to a large part of the total emissions of greenhouse gases, which demands for increased sustainability in all phases of a buildings’ lifecycle. Choices of building materials and the respective required maintenance and replacements are becoming more important if further reductions of climate impacts should be obtained. Folkhem is a Swedish construction company who constructs multi-storey buildings made of wood. The company has shown interest in developing knowledge about how the selection of building materials effects the impacts on climate, the extent of necessary maintenance and replacement work as well as economic consequences. The aim of this master thesis was to evaluate the potential climate impacts and costs for different scenarios of maintenance and replacements of selected exterior building components for Folkhem’s planned building in Stadshagen, in Stockholm. The façade, roof, windows and balconies have been in focus. To fulfill the aim of this study, life cycle assessment and a simplified cost analysis have been carried out. With the basis of the results from this study, recommendations of building materials for the chosen building components in Folkhem’s planned building have been stated. A façade made of pine impregnated with boiled linseed oil is recommended as façade cladding, and OrganoWood is recommended for the balcony decking. Folkhem planned to use wooden windows, but it is recommended that these are substituted to aluminum coated wooden windows. No recommendation could be provided for the roof from this study. The following conclusions have been made; More attention should be payed to the phases of maintenance and replacement when carrying out LCAs for timber buildings, since general assumptions could be misleading. The origin of the building materials could have a significant climate impact if several replacements need to be performed, since this includes a large number of transports of materials. Different building materials or building components have different lifespans and needs for maintenance. To reduce costs and potential climate impacts, long lifespans with little need for maintenance are desired. Planning for a specific lifespan of the building and the required maintenance and replacements may contribute to reduce the potential climate impacts. Maintenance is recommended for timber buildings, since this could reduce the need for replacements, which could reduce the potential climate impacts. LCA can be a useful tool for Folkhem to plan for maintenance and replacements of their timber buildings if improvements are performed regarding LCA data quality. LCA can provide guidance for Folkhem to choose sustainable building materials, with regards to maintenance and replacements at an early stage in the design process. A future study could be to perform a more detailed LCA of the materials and products that required assumptions in this study, for instance the surface treatments for maintenance. A more detailed LCA of all maintenance that should be conducted in a building could be of interest as well, and to investigate the impacts from excluded processes in this study. Alternative building materials for the exterior building components could be evaluated as well as different percentages of painting area. More impact categories than climate change could also be evaluated. Impacts from the building lifecycle phases of repair and refurbishment could also be interesting to evaluate in order to receive an overview of the total potential climate impacts and costs from all parts of the lifecycle of a building. Another approach could be to investigate if maintenance and replacement are carried out as described from technical literature and manufacturers in reality. Finally, a more thorough cost analysis could be carried out, evaluating how a housing society would be affected from costs from maintenance and replacement.

<p>    </p> <p>Electronic waste is one of the fastest growing waste streams, spurred by their rising market and demand. However, these devices contain an array of metals that is recyclable for economic and environmental benefit through secondary manufacturing. As the turnaround rate for newer models quickens, consumers are motivated to purchase novel devices, leaving their current ones behind. Focusing on how United States (U.S.) households manage their electronics, a top-down approach stock and flow STELLA model was created to model the lifecycle of eight common electronics. Input data for the model came from a public online survey directed to U.S. household owning adults. From the model, a metallic stock and flow analysis was conducted to quantify the trends, environmental footprint, and economic value of stored devices in U.S. households and how it compares to devices being used, disposed, and recycled. The number of stored devices in the U.S. was found to be increasing annually with a stored amount of over 757 million stored individual electronic devices, nearly half of which originate from cell phones, carrying an economic value of 32.6 billion US dollars (USD) and carbon emissions of 7.6 billion kilograms (kg) from their metallic components alone for the year 2020. Most of the pollution and economic value stems from precious metals (PMs) and in a circular economy, these stored metals can have a significant impact to the environment and economy through recycled. Also, with advancing capabilities of smartphones, the metallic composition for device components of Samsung galaxy smartphones was quantified to assess their evolving metallic content. With the growing market of electronic devices, knowing the value and importance of devices currently in U.S. households is critical. This underlies the influence of sustainable design through a circular economy to push initiatives to manufacture recyclable friendly devices, expand the metal recycling industry, and motivate citizens to properly handle their stored devices. </p>

<p>Biomass liquefaction is a nascent field within biorefinery research and has arisen in response to the bottleneck created from materials handling at the front end of the biorefinery. The basic concept is that if the biomass were to be converted into a flowable slurry at the front-end of the process, then the material could smoothly flow into the biorefinery pretreatment and down time due to the material forming a plug would be minimized or eliminated. Three liquefaction routes were studied in this work. These routes were: enzyme route, enzyme mimetic route, and a combined route of enzyme and enzyme mimetic. Through a Techno-economic assessment (TEA), it is possible to determine which route is most-economical to scale up and also to understand the extent to which liquefaction increases/decreases of the price of the biorefinery product.</p> <p>Gasification is a bio-based technology that has recently acquired more attention as it is an efficient conversion process for a variety of feedstocks. As new techniques and process routes are discovered, it is important to analyze which process technique is feasible for commercial scale up, as the highest performing technique may not be the most economical option to pursue. Along the same philosophy, a process concept was developed on Aspen Plus® to treat syn-gas impurities and also recycle the spent solvents. A TEA study was performed to determine the unit cost of treatment and to explore avenues of cost saving.</p>

För att kunna uppnå de tuffare materialåtervinningsmålen som börjar gälla i Sverige år 2020 måste utsorteringen av bland annat plast-, papper- och metallförpackningar öka. Hushållsavfall beskrivs som en av de mest miljöpåverkande kategorin av avfall men samtidigt den kategori där det finns mest potential för förbättringar genom bättre hantering. Plockanalyser från 67 procent av Sveriges kommuner mellan åren 2013 och 2016 visar att ett svenskt villahushålls restavfall innehåller 34,5 procent förpackningar och returpapper som skulle kunna sorteras ut för materialåtervinning. Ett sätt att öka utsorteringen av producentansvarsmaterial från restavfallet och då kunna uppnå materialåtervinningsmålen är att kommuner erbjuder enklare samt ökad service i form av källsortering närmare hushållen. Tidigare studier har jämfört systemen optisk sortering och fyrfackskärl, som båda innebär källsortering närmare hushållen, med det vanligaste systemet i Sverige idag, tvåkärl, som inte innebär en ökad service genom kvalitativa metoder. Systemen har inte jämförts med kvantitativa metoder utifrån ekonomi eller miljö och inte heller med ett nytt koncept som heter Kvartersnära insamling. Den här rapporten har därför jämfört de fyra systemen utifrån aspekterna miljö och ekonomi med hjälp av verktygen livscykel- och livscykelkostnadsanalys som applicerades i ett område i Kristinehamns kommun för att på så sätt komma närmare verkligheten. Resultatet visar att systemet kvartersnära insamling har lägst miljöpåverkan i de undersökta miljöpåverkanskategorierna och därefter fyrfackskärl, optisk sortering och högst miljöpåverkan har systemet tvåkärl utifrån förutsättningarna och antagandena som har applicerats i studien. Livscykelanalysen visar att miljönyttan med materialåtervinningen överväger konsekvenserna av ökade transporter. Systemet med lägst livscykelkostnad är tvåkärl och sedan kvartersnära insamling, optisk sortering och dyrast livscykelkostnad har fyrfackskärl utifrån antaganden och de förutsättningar som använts i studien. En slutsats från rapporten är att det är viktigt att även undersöka andra aspekter förutom ekonomi och miljö vid val av insamlingssystem då resultatet till stor del beror på andra aspekter bland annat användarens uppfattning om systemet. / To achieve the stricter material recycling goals in Sweden in 2020 plastic-, metallic- and paper packages need to be better sorted from the household waste. Household waste might have the highest environmental impact compared with other sorts of waste but household waste has the highest potential to lower its impact. Waste pick-up analysis from 67 percent of Sweden's municipalities between 2013 and 2016 show that a Swedish household waste contains 34.5 percent packaging and recycled paper that could be sorted for recycling. The producers of that material have the responsibility to collect it but it does not work as well as planned because of different circumstances. One way to increase the recycling of the material from the household waste and then achieve the material recycling goals is that municipalities offer simpler and increased service in the form of source sorting closer to the households. Previous studies have compared the systems of optical sorting and multi compartment bin, which offer separation at sources closer to the households. Moreover, those systems have been compared with the most common system in Sweden today, two bins, which do not involve increased service. The systems have not been compared with quantitative methods based on economics or the environment, nor with a new concept called district collection. This report has compared the four systems. The aspects that have been compared are the environmental aspects and economical aspects by using the tools lifecycle assessment and lifecycle cost assessment. Moreover, the systems have been fictive studied in an area in the municipality of Kristinehamn, in order to get closer to reality. The results indicate that the collection system district collection had the lowest environmental impact followed by multi compartment bin and then optical sorting. Moreover, the system with two bins has the highest impact in the studied environmental impact categories according to the assumptions that have been applied in the study. The lifecycle assessment indicates that the benefits with material recycling is higher than the environmental impacts of increased transportation. The system with lowest lifecycle cost is the system with two bins and then the district collection. The system with highest lifecycle cost is the system optical sorting and the system with the second highest cost is multi compartment bin according to the assumptions that have been applied in the study. One conclusion from the study is that it is important to investigate more aspects than environmental impact and costs when to decide collection system. It is because the results depends on the other aspects as well like the users experience about the system.

Images have become a ubiquitous and efficient data form to record information. Use of this option for data capture has largely increased due to the widespread availability of image sensors and sensor platforms (e.g., smartphones and drones), the simplicity of this approach for broad groups of users, and our pervasive access to the internet as one class of infrastructure in itself. Such data contains abundant visual information that can be exploited to automate asset assessment and management tasks that traditionally are manually conducted for engineering systems. Automation of the data collection, extraction and analytics is however, key to realizing the use of these data for decision-making. Despite recent advances in computer vision and machine learning techniques extracting information from an image, automation of these real-world tasks has been limited thus far. This is partly due to the variety of data and the fundamental challenges associated with each domain. Due to the societal demands for access to and steady operation of our infrastructure systems, this class of systems represents an ideal application where automation can have high impact. Extensive human involvement is required at this time to perform everyday procedures such as organizing, filtering, and ranking of the data before executing analysis techniques, consequently, discouraging engineers from even collecting large volumes of data. To break down these barriers, methods must be developed and validated to speed up the analysis and management of data over the lifecycle of infrastructure systems. In this dissertation, big visual data collection and analysis methods are developed with the goal of reducing the burden associated with human manual procedures. The automated capabilities developed herein are focused on applications in lifecycle visual assessment and are intended to exploit large volumes of data collected periodically over time. To demonstrate the methods, various classes of infrastructure, commonly located in our communities, are chosen for validating this work because they: (i) provide commodities and service essential to enable, sustain, or enhance our lives; and (ii) require a lifecycle structural assessment in a high priority. To validate those capabilities, applications of infrastructure assessment are developed to achieve multiple approaches of big visual data such as region-of-interest extraction, orthophoto generation, image localization, object detection, and image organization using convolution neural networks (CNNs), depending on the domain of lifecycle assessment needed in the target infrastructure. However, this research can be adapted to many other applications where monitoring and maintenance are required over their lifecycle.