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- Lindkvist, Emma, 1984-
(författare)
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System studies of biogas production : comparisons and performance
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Biogas has the potential to be part of the transition towards a more sustainable energy system. Biogas is a renewable energy source and can play an important role in modern waste management systems. Biogas production can also help recirculate nutrients back to farmland. Besides all this, biogas is a locally produced energy source with the potential to increase global resource efficiency, since it can lead to more value and less waste, as well as decreased negative environmental effects. However, biogas production systems are complex, including different substrates, different applications for biogas and digestate, and different technology solutions for digestion, pre-treatment and for upgrading the raw gas. To increase the development of biogas production systems, knowledge sharing is a key factor. To increase this knowledge sharing, comprehensible analysis and comparisons of biogas production systems are necessary. Thus, studies are needed to verify the resource efficiency of biogas production systems from different perspectives.The aim of this thesis is to perform a systems analysis of biogas production systems and to explore how to analyse and compare biogas production systems. An additional aim is to study biogas production systems from a systems perspective, with a focus on environment, energy and economy. Studying biogas production systems from different system levels, as well as from different approaches, is beneficial because it results in deeper knowledge of biogas systems and greater opportunities to identify synergies.Systems studies of biogas are important, since biogas systems are often complex and integrated with other systems. In this thesis, biogas systems analyses are performed at different levels. In the widest system study, classifications of different biogas plants are analysed and classifications in different European countries are compared, with the prospect of paving the way for a new common classification for biogas plants in Europe. Today, classifications vary between countries, and hence comparisons of plants in different countries are difficult. In the narrowest system study, a new methodology for analysing energy demand at different biogas production plants has been developed. The aim was to develop a methodology that is applicable for all kinds of biogas plants with energy inputs. The methodology describes the process of analysing energy demand and allocating energy to sub-processes and unit processes.Further, an approach for assessing the resource efficiency of different treatment options for organic waste was designed. The approach includes environmental, economic and energy perspectives, and was applied to five different regions with several food manufacturing companies. A study of treatment options for organic waste from a single food company was also conducted. The results showed that biogas production is a resource-efficient way to treat waste from the food industry. The approach enables a wider analysis of biogas systems, and the results from the applications show the complexity of assessing resource efficiency. It is also shown that it is important to understand that the resource efficiency of a system is always in relation to the substituted system.In this thesis, three different approaches to analysing biogas production systems are presented: categorization, resource efficiency analysis and energy demand analysis. These approaches all contribute to the understanding of biogas systems and can help, in different ways, to increase knowledge about biogas systems in the world. If knowledge about different biogas systems can be easily disseminated, more of the unused potential of biogas production may be realized, and hence more fossil fuels can be replaced within the energy system.
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| 2. |
- Kastbom, Lisa, 1978-
(författare)
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A good death from the perspective of patients with severe illness and advance care planning (ACP) in patients near end-of-life
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Previous research has indicated that what constitutes a good death is heterogenic and complex although there are some recurrent themes and similarities regardless individual background factors. Studies on advance care planning (ACP), i.e. making proactive plans regarding content of care and treatment limitations, on nursing home (NH) patients are rare. Positive effects of ACPs are shown, but also that these often are lacking. The overall aim with this thesis was to explore the perceptions of a good death from the perspective of patients with severe illness and to investigate, from different perspectives, experiences of ACP in a NH context. In paper I, patients with cancer in a palliative phase were interviewed on their perceptions of a good death. Death was viewed as a process and previous experiences on the death of others influenced their own perceptions. A good death was associated with living with the prospect of imminent death, preparing oneself and others for one’s death and dying comfortably, e.g. without suffering, with independence and with social relations intact. Some were comforted by their belief that death is predetermined, and that after death, there is something else. Others felt uncomfortable when they viewed death as the end of the existence. In paper II, nurses and physicians were interviewed on their experiences of the factors that shape the ACP process in NHs. Exploration of the patient’s preferences regarding content of care and treatment limitations was important, as well as integration of the patient’s preferences and the views of the family members and staff concerning these questions. ACP documentation had to be clear, updated and available for staff and the implementation and reevaluation of ACP were also considered important, according to the participants. Significance of clinicians’ perceiving beneficence as well as fear of accusations of maleficence were shown to be essential factors to contemplate. In a retrospective chart review (paper III), medical records of 367 deceased NH patients were analysed. A high prevalence of ACP was shown, using two different definitions of ACP (ACP I and ACP II). Moreover, adherence to the ACP content was strong and positive associations were seen between ACP and variables of the three research aims, such as: diagnosis (dementia), physician attendance at NH and end-of-life (EOL) care. In paper IV, family members of deceased NH patients were interviewed on their experiences of ACP in NHs. EOL issues were challenging to talk about, although the family members appreciated staff raising these questions. The patient’s preferences were sometimes explicitly or implicitly communicated. However, in some cases, family members had a feeling of the patient’s preferences, although they had not been clearly communicated. Everyday details symbolised staff commitment. The family members viewed the nurse as central. The physician was described as absent and ACP meetings often went unnoticed. Both involvement and lack of involvement could cause the family members feelings of guilt. In conclusion, we found that what constitutes a good death is highly individual, although recurrent themes are seen. EOL conversations are important and challenging and need staff training and experience. It seems important to support healthcare staff not only to initiate ACP in NH patients, but also to involve the patient and family members in the ACP and planning EOL care. Making proactive plans regarding content of care including treatment limitations, could enable patient autonomy, optimise the chances for the patient to experience a good death and enhance for the family members during the dying trajectory and after the patient’s death.
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| 3. |
- Lawrence, Akvile, 1976-
(författare)
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Energy Management for Improved Energy Efficiency in the Pulp and Paper Industry : Success Factors for Strengthening Drivers and Overcoming Barriers
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Industrial energy efficiency improves the profit and competitive advantage of companies. The pulp and paper industry (PPI)being one of the five most energy-intensive industries uses 5.6% of global industrial energy, according to the InternationalEnergy Agency. It is one of the key sectors that is faced with the challenge of improving energy efficiency (EE). The PPI isnot less important in Sweden where it uses approximately 52% of the total industrial energy, employing more than 20000people and where improvement of the energy end-use by 1% corresponds to estimated savings of approximately 218 MSEKannually. Energy management (EnM) is a means for improving EE. However, despite research showing the possibility forannual improvement of the energy end-use by 5.5-19.4% by technical measures, EnM is not always used to its full potentialor often hardly implemented, resulting in an EE gap, i.e. the difference between the theoretical practically and cost-effectivelyachievable EE and actual EE. Why then does this EE gap exist? What are the drivers for and barriers to practicing EnM to itsfull potential and thus improving energy efficiency? What are the success factors for encouraging the drivers and overcomingthe barriers? What practical recommendations can be made that could lead to the improvement of energy efficiency? Afterextracting information from historical and current information using tools from multivariate data analysis (MDA), this PhDdissertation presents new knowledge that intends to contribute to overcome the challenges of improving energy efficiency inthe PPI. Specifically, international research primarily addressing EnM in the PPI showed that EnM in the PPI is perceived asEnM via technology, despite that EnM contains other aspects than EnM via technology, e.g. proactive EnM practices. Thisresult indicates the presence of a knowledge-gap on how to deploy EnM in the PPI. Studies on the PPI in Sweden showeddifferent EnM practices among the individual types of mills, i.e. pulp mills, paper mills and integrated-pulp and paper mills.Integrated mills seemed to measure the energy-related performance more than pulp mills and paper mills. However, the resultsalso suggested that the Swedish PPI worked continuously and regularly with EnM. Further, aside from the top ranked perceiveddrivers being economical and the barriers being organizational, knowledge related drivers and barriers were amongst the mostimportant. The results also showed that commonly only selected employees were trained in EnM, which indicated thatcommunication between the trained employees and operations personnel as well as the absorptive capacity for energy issuescould potentially be improved. Additionally, research showed that by using MDA, previously unstudied and unidentifiedconnections could be discovered. Namely, MDA showed that during the ten-year voluntary agreement policy program knownas PFE (Program for improved electricity efficiency in energy-intensive industry), less financially stable and less experiencedwith EnM companies tended to save electricity more than the more financially stable and more EnM experienced companies.Altogether, the success factors for EnM for improving energy efficiency could be summarized in the versatile 4M memorytool - The “4M for energy efficiency”: mind, measure, monitor and manage. The “4M for energy efficiency” suggests that allthe four “Ms” should be practiced simultaneously in order to maximize the achievement of goals of EnM.
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| 4. |
- Haraldsson, Joakim, 1990-
(författare)
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Improved Energy Efficiency in the Aluminium Industry and its Supply Chains
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Energy is an essential resource in the daily lives of humans. However, the extraction and use of energy has an impact on the environment. The industrial sector accounts for a large share of the global final energy use and greenhouse gas (GHG) emissions. The largest source of industrial GHG emissions is energy use. The production and processing of aluminium is energy- and GHG-intensive, and uses significant amounts of fossil fuels and electricity. At the same time, the global demand for aluminium is predicted to rise significantly by the year 2050. Improved energy efficiency is one of the most important approaches for reducing industrial GHG emissions. Additionally, improved energy efficiency in industry is a competitive advantage for companies due to the cost reductions that energy efficiency improvements yield.The aim of this thesis was to study improved energy efficiency in the individual companies and the entire supply chains of the aluminium industry. This included studying energy efficiency measures, potentials for energy efficiency improvements and energy savings, and which factors inhibit or drive the work to improve energy efficiency. The aim and the research questions were answered by conducting a literature review, focus groups, questionnaires and calculations of effects on primary energy use, GHG emissions, and energy and CO2 costs.This thesis identified several energy efficiency measures that can be implemented by the individual companies in the aluminium industry and the aluminium casting foundries. The individual companies have large potentials for improving their energy efficiency. Energy efficiency measures within the electrolysis process have significant effects on primary energy use, GHG emissions, and energy and CO2 costs. This thesis showed that joint work between the companies in the supply chains of the aluminium industry is needed in order to achieve further energy efficiency improvements compared to the companies only working on their own. The joint work between the companies in the supply chain is needed to avoid sub-optimisation of the total energy use throughout the entire supply chain. Better communication and closer collaboration between all the companies in the supply chain are two of the most important aspects of the joint work to improve energy efficiency. An energy audit for the entire supply chain could be conducted as a first step in the joint work between the companies in the supply chains. Another important aspect is to increase the use of secondary aluminium or remelted material waste rather than primary aluminium.The companies in the Swedish aluminium industry and the aluminium casting foundries have come some way in their work to improve energy efficiency within their own facilities. However, the results in this thesis indicate that cost-effective technology and improved management can, in total, save 126–185 GWh/year in the Swedish aluminium industry and 8–15 GWh/year in the Swedish aluminium casting foundries.This thesis identified several demands regarding economics, product quality and performance, and environment placed on the companies and products in the supply chains that affect energy use and work to improve energy efficiency. These demands can sometimes counteract each other, and some demands are more important to meet than improving energy efficiency. This implies that improving the energy efficiency of the supply chains as well as designing products so they are energy-efficient in their use phase can sometimes be difficult. The results in this thesis indicate that it would be beneficial if the companies reviewed these demands to see whether any of them could be changed.Both the economic aspects and demands from customers and authorities were shown to be important drivers for improved energy efficiency in the supply chains. However, placing demands on energy-efficient production and a company’s improved energy efficiency would require those placing the demands to have deeper knowledge compared to demanding green energy, for example. Requiring a company to implement an energy management system to ensure active work to improve energy efficiency would be easier for the customer than demanding a certain level of energy efficiency in the company’s processes. Additionally, energy audits and demands on conducted energy audits could act as drivers for improved energy efficiency throughout the supply chains.This thesis showed that the most important barriers to improved energy efficiency within the individual companies include different types of risks as well as the cost of production disruption, complex production processes and technology being inappropriate at the site. Similar to the supply chains, important drivers for improved energy efficiency within the individual companies were shown to be economic aspects and demands from customers and authorities. However, the factors that are most important for driving the work to improve energy efficiency within the individual companies include the access to and utilisation of knowledge within the company, corporate culture, a longterm energy strategy, networking within the sector, information from technology suppliers and energy audits.
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