Lifecycle energy and greenhouse gas emissions analysis of biomass‐based 2‐ethylhexanol as an alternative transportation fuel

This study investigates the environmental performance of 2‐ethylhexanol (2‐EH), as a potential drop‐in transport fuel alternative. Three different biomass‐based production pathways are evaluated and compared using life cycle assessment (LCA) methodology. The environmental impact of 2‐EH is assessed in terms of cumulative energy demand (CED) and global warming potential (GWP). Among the three alternative pathways, 2‐EH produced via syngas results in the lowest primary energy demand and GHG emissions under the baseline assumptions of this work. The two biochemical production pathways (via ethanol and butanol) exhibit higher CED and GWP during biomass conversion steps mainly due to process materials and chemicals used. Process specifications such as transport distance to production facility or the fate of the obtained by‐products are shown to influence the overall environmental impact of the fuel for all studied pathways. The use phase performance of 2‐EH was also considered in this work, as part of a 100% renewable blend and was compared to existing fossil and renewable fuels. The studied blend has the potential to reduce GHG emissions by more than 85% compared to fossil diesel while when certain production pathways are followed, it exhibits lower GWP than renewable fuels already in the market such as ethanol blends and biodiesel. 2‐EH can therefore provide a competitive alternative to fossil transport fuels increasing the share of renewable content in the current vehicle fleet, thus enhancing the efforts for a sustainable transport sector. Document type: Articl

RED, PEF, and EPD: Conflicting rules for determining the carbon footprint of biofuels give unclear signals to fuel producers and customers

Biofuel producers and other commodity suppliers are increasingly affected by conflicting rules for life cycle assessment (LCA). They may get multiple requests for LCAs to be used in various contexts, which require the application of different methodological approaches that vary in scope, system boundaries, data demand, and more. This results in increased cost and competence requirements for producers, as well as confusion among other actors including their customers. Differences in methodologies might also lead to various outcomes, conclusions and conflicting guidance regarding which fuels to prioritize or develop. We have analyzed the actual differences when applying three different frameworks: the EU Renewable Energy Directive (RED), the EU framework for Product Environmental Footprints (PEF), and the framework of Environmental Product Declarations (EPD), which have different modeling requirements. We analyzed the methods from a conceptual point of view and also applied the methods to estimate the carbon footprint on a wide range of biofuel production pathways: (i) ethanol from corn, (ii) fatty acid methyl ester (FAME) from rapeseed oil, (iii) biogas from food waste, (iv) hydrogenated vegetable oil (HVO) from rapeseed oil, and (v) HVO from used cooking oil. Results obtained for a specific fuel could differ substantially depending on the framework applied and the assumptions and interpretations made when applying the different frameworks. Particularly, the results are very sensitive to the modeling of waste management when biofuel is produced from waste. Our results indicate a much higher climate impact for, e.g., biogas and HVO produced from used cooking oil when assessed with the PEF framework compared to the other frameworks. This is because PEF assigns at least part of the production of primary materials and energy to the use of recycled material and recovered energy. Developing Category Rules for biofuels for PEF and EPD ought to help clarifying remaining ambiguities

Well-to-tank data for advanced tailor-made biofuel alternatives

The transport sector accounts for almost 25% of Europe\u27s GHG emissions and is the main cause of air pollution in cities. As part of the effort to increase the sustainability of the transport sector, and to reach the national vision for a vehicle fleet that is independent of fossil fuels by 2030 Sweden set of goals for an increased share of renewables in the transport sector, also following the EU target of at least 10% by 2020. The major goal, for the larger project, is to contribute with applicable data for promoting the best biofuel alternatives for a medium term future with both improved engine combustion concepts and sustainable production pathways. Feedstock potential and integration opportunities with existing industry infrastructure for improved techno-economic and environmental production performance will also be an inherent part of the biofuels analysis of WTT performance. In this literature review focus is on finding different relevant pathways for the production of biomass based drop-in fuels such as n-octanol, 2-ethyl-hexanol, n-decanol, 2-propyl-heptanol, DNBE, 2-MTHF, Caromax, and PolyDME (or POMDME or OME). To illustrate the methodology, one of the Diesel-like biofuels – 2-ethylhexanol – has been chosen and three different production pathways are analyzed for their energy performance. 2-ethylhexanol can be produced via the following three routes: (1)Butanol-based via Guerbet condensation, (2)Ethanol-based via the intermediate product n-butyraldehyde, and (3) Gasification-based via OXO-synthesis. The performance of the three routes will be compared to results for other biofuels serving as Diesel drop-i

A COMPARATIVE ASSESSMENT OF CURRENT AND FUTURE FUELS FOR THE TRANSPORT SECTOR

To facilitate the transition to a sustainable and less fossil dependent transport sector in the short to medium term, the current fuel mix needs to be enriched with renewable fuel alternatives. The present work aims to assess and highlight the opportunities for current and future biomass based fuels to be utilized. Seven fuels and fuel blends fulfilling the EN590 diesel fuel standard have been selected and are compared using qualitative and quantitative criteria covering technical, environmental and economic attributes of the fuels. Mature fuels such as dimethyl-ether (DME) and hydrotreated vegetable oils (HVO) are ranked higher in the assessment due to the increased possibility for environmental gains at moderate costs. For future fuels to be competitive stricter regulation in terms of GHG emissions savings are needed

Methodological Approaches to End-Of-Life Modelling in Life Cycle Assessments of Lithium-Ion Batteries

This study presents a review of how the end-of-life (EOL) stage is modelled in life cycle assessment (LCA) studies of lithium-ion batteries (LIBs). Twenty-five peer-reviewed journal and conference papers that consider the whole LIB life cycle and describe their EOL modelling approach sufficiently were analyzed. The studies were categorized based on two archetypal EOL modelling approaches in LCA: The cutoff (no material recovery, possibly secondary material input) and EOL recycling (material recovery, only primary material input) approaches. It was found that 19 of the studies followed the EOL recycling approach and 6 the cutoff approach. In addition, almost a third of the studies deviated from the expected setup of the two methods by including both material recovery and secondary material input. Such hybrid approaches may lead to double counting of recycling benefits by both including secondary input (as in the cutoff approach) and substituting primary materials (as in the EOL recycling approach). If the archetypal EOL modelling approaches are not followed, it is imperative that the modelling choices are well-documented and motivated to avoid double counting that leads to over- or underestimations of the environmental impacts of LIBs. Also, 21 studies model hydrometallurgical treatment, and 17 completely omit waste collection

Bioenergy and links to agriculture & LULUCF in a Nordic context

publishedVersio

Opto-mechanical design for sight windows under high loads

In this study, the design aspects of optically accessible pressure vessels are investigated via a case study of a High Pressure Combustor experimental rig. The rig was designed to take optical measurements of combustion, simulating the conditions found in internal combustion engines and turbines. Although, it is not new to equip chambers and reactors with sight windows, important aspects of design and relevant information regarding optical access is missing or are insufficiently explored or not readily accessible in the existing literature. A comprehensive review of requirements for optical access to such high-pressure, high-temperature systems has been conducted. It is shown in a readily-navigable format as function of application and precision, with data and technical correlations hitherto not found in a ‘user-friendly’ style. The material selection procedure is detailed and supported by a complete comparison of optical materials and relevant properties. The review revealed a significant inconsistency in mechanical properties claimed in the literature for optical materials. As a response to this, increased safety factor values are suggested as function of level of uncertainties and effects of failure, typically three to four times higher than the industrial standard. Moreover, newly developed equations are presented linking performance analysis to the design criteria

What Stops Designers from Designing Sustainable Packaging?—A Review of Eco-design Tools with Regard to Packaging Design

Packaging has caused much waste and its sustainability has received much attention in the past decades. Designers have made efforts to mitigate environmental impacts of packaging. However, many packaging designs are still far from achieving their sustainability goals. The purpose of this study is to perform a literature review of the principal design methods and tools for sustainable packaging published over the last twenty years. The objective is to understand the main obstacles that limit their effective implementation in the packaging design process. This study develops a sustainable packaging design and development model and proposes criteria for accessing packaging tools and methods. This study has found that to achieve sustainable design, many tools have limitations in demonstrating usage and balancing trade-off situations. Most of the tools focus on defining problems rather than suggesting possible solutions