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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Energiomställning inom Sågverksindustrin : En utforskande undersökning av sågverksindustrins framtida energianvändning / Energy Transition in the Sawmill Industry : An exploratory study of the future energy use in the sawmill industry

Fredriksson, Hanna, Andreassen, Daniel January 2023 (has links)
The transition to a fossil-free industry is a current topic, and in Swedish industry, energytransition of existing energy systems is promoted to reduce climate impact. Energy transitioninvolves a structural change in the energy system with a focus on energy use and energysupply. To reduce global greenhouse gas emissions, the transition can be achieved throughelectrification and the use of biomass. Currently, sawmills combust significant amounts of biomass to meet the heat demandof industrial wood drying. As the biomass used is a by-product of the sawmills’ otherproduction processes, this combustion is usually considered sustainable and circular. However,some research indicates that increased biomass usage in several industrial sectors can leadto overexploitation of the resource with negative environmental impacts. Despite thesedisagreements, many argue that bio-based residual flows must be utilised efficiently to meetsociety’s future biomass needs. Against this background, it needs to be examined whether sawmills should continue tocombust biomass or whether an energy transition would be more economically and ecologicallysustainable. The aim of this study is to investigate how energy use in the sawmill industrywill change in the future and what potential consequences this change may have. In addition,the possibilities and feasibility of electrifying the drying process in the sawmill industryare investigated. To achieve this purpose, a literature search and an interview study wereconducted. The results from these parts form the basis for a scenario-based quantitativestudy of the consequences of different energy transition cases. The results show that future energy use in the sawmill industry will be affected by severalfactors. One important factor is the price of biomass, which can provide an incentive toelectrify the energy-intensive drying process. However, it can be challenging to make anelectrified drying process profitable, and until then energy efficiency will be prioritised ratherthan biomass replacement. The results also indicate that electrification of the drying processcan reduce the climate impact, assuming that the electricity source is fossil-free. The releasedbiomass can then be used more efficiently than incineration, and the optimal use may be toproduce long-life products. Clear knowledge gaps have been identified regarding the electrification of the drying processand its potential consequences. Since the sawmill industry is not ready for an energytransition today, there is time to fill these gaps and develop the electrifying processes. Furtherinvestigations should be conducted on various aspects of electrified drying through in-depthmodelling and analysis of the sawmill energy system. Additionally, future studies couldinvestigate the extent of the impact of sawmill biomass release on the surrounding energysystem.
2

Sustainable production of bio-energy products in the sawmill industry

Vidlund, Anna January 2004 (has links)
<p>One of the great challenges facing society is to convert theglobal energy system to a sustainable process. Currently, 80%of the world´s energy is supplied through the combustionof fossil fuels. Not only are the fossil resources limited, theutilisation also increases the level of greenhouse gases in theatmosphere. The convertion to a sustainable energy system isproblematic since the technology needed to exploit mostnon-fossil energy sources is not yet fully developed, e.g.solar energy. Biofuel is an available renewable energy sourcewhich is already widely used in many countries. If an effectiveswitch-over from fossil fuels to biofuels is to be realised,biofuels must be viewed as a limited resource. Consequently, itis important that the handling, upgrading and utilisationprocesses involving biofuels are efficient so that itspotential can be fully exploited.</p><p>This thesis considers efficient biofuel utilisation andupgrading within the sawmill industry. The goal has been toanalyse not only the technical opportunities for energy savingsin the sawmill industry, but also to analyse the costeffectiveness and environmental impact of studied measures. Theheat demand of the sawmill industry is almost completelycovered by its own by-products; primarily bark, sawdust andwood chips. The increased demand and improved economic value ofwoody biofuels on the market is thus an incentive for thesawmill industry to place more focus on energy issues. Thesawmill industry also has a more or less constant heat loadover the year, which is a beneficial factor for integrationwith district heating networks, biofuel upgrading plants andcombined heat and power plants.</p><p>The conclusion of the study is that a variety of energyproducts such as heat, unrefined biofuel, pellets andelectricity can be efficiently produced in the sawmill industryand sold for profit to external customers. The payback periodsfor the proposed investments are moderate and both theemissions of volatile organic compounds and global CO2 aredecreased. Should the proposed measures be fully implemented atSwedish sawmills, about 2.8 TWh of biofuel could be savedannually, 0.5 TWh of waste heat could be sold as districtheating and 0.8 TWh of green electricity could be produced.Language: English</p><p><b>Keywords:</b>Sawmill industry, energy efficiency, heatrecovery, integration, biofuel, upgrading, district heating,fuel pellets, CHP, VOC, CO2</p>
3

Customers' logistics service requirements and logistics strategies in the Swedish sawmill industry

Gustafsson, Åsa January 2006 (has links)
The future of the sawmill industry is uncertain; this is partly due to its internal structural changes, but also due to structural changes amongst their customers. Concurrently, competition within the industry is increasing, and therefore focus is constantly being placed on reducing costs and leveraging economies of scale. However, in order for sawmills to benefit from economies of scale, it is necessary to work with a well thought-out logistics strategy. This doctoral dissertation aims at identifying and describing the customers' logistics service requirements as well as describing and analyzing logistic strategies in the sawmill industry. The dissertation identifies and defines some of the sawmills customers' logistics service requirements and establishes a theoretical framework for logistics strategies, as well as it studies logistics strategies in the sawmill industry. House-builders and traditional retailers appear to focus on similar logistics service requirements, whereas the logistics service requirement of the DIY multiple retailers differ. Furthermore, this dissertation provides a general definition of logistics strategy that has been operationalized by generic logistics strategies. The sawmill industry makes use of generic logistics strategies such as differentiation and postponement. The individual sawmills ought to consider improving their process performance by implementing additional generic logistics strategies as well as increasing their utilization of generic logistics strategies that are already implemented. The sawmill industry's utilization of generic logistics strategies is however restricted by its own supplier market (including uncertainties of quality of incoming material), and also by the inherent nature of commodity products, as well as divergent material flows.
4

Supply chain management and industry cyclicality:a study of the Finnish sawmill industry

Holma, H. (Heikki) 02 May 2006 (has links)
Abstract The aim of this study is to deepen current understanding concerning cyclicality in the Finnish sawmill industry. Traditionally, economic actors in the sawmill industry have faced dramatic price and demand fluctuations. Managers often regard cyclicality as natural and unavoidable in the industry. Accordingly, research related to business cycles in the Finnish sawmill industry has consisted of short-term studies that have mainly focused on predicting the turning points of cycles. In contrast to these short-term investigations, this study proffers research on cyclicality that is both empirical and historical. It aims to emphasise the actor perspective that seems to be absent in existing research on business cycles and cyclicality. In line with the adopted perspective, business cycles are not merely objective economic phenomena external to their observers. As regards the research, the above view necessitates a more complete understanding of business cycles and historical knowledge of the industry and the actors in its supply chain. The idea that heavy economic fluctuation is detrimental to all is emphasised in this thesis, though it has been argued that in the short term, some actors at the lower end of a distribution chain may take advantage of cyclicality by game playing. However, in the long run there are very few actors, if any, who profit from business cycles. The empirical data was primarily collected during a number of discussions with sawmill experts and in essence, the problem of cyclicality is observed through the eyes of Finnish sawmill managers. However, interviews with intermediaries as well as many public statistics and archive documents were also used to describe and explain the economic fluctuations over three decades in the industry. Industry-, supply chain- and dyadic business relationship-levels are used in the empirical and theoretical parts of the thesis. Business cycle theories by economists form the context for the study of cyclicality. Systems thinking presents the total picture of cyclicality as a problem in a specific industry, whereas the Bullwhip/Forrester effect describes cyclicality in a supply chain, and explanations for cyclicality in the Finnish sawmill industry are studied in terms of supply chain management. In particular, the presented sub-cases of dyadic business relationships shed light on the power of long-term business relationships as a smoothing-out strategy. The findings of this study reveal that there is another option for managers other than considering the cycles as being "natural", and that there is an opportunity to affect the traditional mode of behaviour in coping with business cycles. It is argued that the structures, behavioural patterns and management components of supply chain management play major roles when the sources of cyclicality and opportunities to moderate business cycles are investigated.
5

Sustainable production of bio-energy products in the sawmill industry

Vidlund, Anna January 2004 (has links)
One of the great challenges facing society is to convert theglobal energy system to a sustainable process. Currently, 80%of the world´s energy is supplied through the combustionof fossil fuels. Not only are the fossil resources limited, theutilisation also increases the level of greenhouse gases in theatmosphere. The convertion to a sustainable energy system isproblematic since the technology needed to exploit mostnon-fossil energy sources is not yet fully developed, e.g.solar energy. Biofuel is an available renewable energy sourcewhich is already widely used in many countries. If an effectiveswitch-over from fossil fuels to biofuels is to be realised,biofuels must be viewed as a limited resource. Consequently, itis important that the handling, upgrading and utilisationprocesses involving biofuels are efficient so that itspotential can be fully exploited. This thesis considers efficient biofuel utilisation andupgrading within the sawmill industry. The goal has been toanalyse not only the technical opportunities for energy savingsin the sawmill industry, but also to analyse the costeffectiveness and environmental impact of studied measures. Theheat demand of the sawmill industry is almost completelycovered by its own by-products; primarily bark, sawdust andwood chips. The increased demand and improved economic value ofwoody biofuels on the market is thus an incentive for thesawmill industry to place more focus on energy issues. Thesawmill industry also has a more or less constant heat loadover the year, which is a beneficial factor for integrationwith district heating networks, biofuel upgrading plants andcombined heat and power plants. The conclusion of the study is that a variety of energyproducts such as heat, unrefined biofuel, pellets andelectricity can be efficiently produced in the sawmill industryand sold for profit to external customers. The payback periodsfor the proposed investments are moderate and both theemissions of volatile organic compounds and global CO2 aredecreased. Should the proposed measures be fully implemented atSwedish sawmills, about 2.8 TWh of biofuel could be savedannually, 0.5 TWh of waste heat could be sold as districtheating and 0.8 TWh of green electricity could be produced.Language: English Keywords:Sawmill industry, energy efficiency, heatrecovery, integration, biofuel, upgrading, district heating,fuel pellets, CHP, VOC, CO2
6

En teoretisk modell av furu för en effektiv produktion av attraktiv furuparkett. : -En studie i effektivt råvaruutnyttjande

Lindqvist, Sven January 2020 (has links)
Wood has in several ways become a sought after material, much thanks to the materials advantages from a sustainability point of view. There are several indicators that this will continue and that the competition of the raw material will increase. The efficient utilization of raw materials is considered central, both from a societal perspective but also for the individual company, which can increase their profitability with a well considered wood. The complexity of the raw material puts great demand on knowledge and logistics to achieve an efficient utilization. This study is a case study that investigates the requirements of the wood for the production of pine parquet at the parquet producer Berg &amp; Berg. To clarify the consumers need, a literature study about the customer preferences about floor has been carried out. To be able to develop a descriptive model on which timber best meets the requirements, from production as well as the customers’ needs, a literature study about pines wood property has been done. This examines how the wood properties vary within logs, between individual trees and between stands. In addition, a description is made of how the raw material is handled by the forest and sawmill industry with the help of literature studies. The wood properties that are important for the customer when buying flooring is the visual appearance in which an even distribution of knots is the most desirable. Dry knots create problems with rework in the production. The most suitable wood is obtained from stands with a lower site index. It’s the middle part of the trunk that meets the requirements for an even knot structure with a larger green-knot zone with a lower proportion of juvenile wood. A one-sided focus on increased volume and lower production costs in forestry and sawmill industry, as well as information barriers between different players in the production chain, makes it more difficult to efficiently utilize the raw material where a more customer oriented range is received. With good knowledge about wood properties, a simple tree model can be derived. For a producer, the tree model can simplify the communication with wood suppliers to obtain a more customer oriented wood.
7

Safety shortcomings within a sawmill facility : How can Virtual Reality Simulators and RFID potentially decrease the most common identified causes?

Torudd, Johan, Olsson, Marcus January 2019 (has links)
In a changing and globalized world, companies are faced with an ever-increased competition. This rapid change has made a big impact, where automation, complex production and customization are common requirements in order to stay competitive. Due to more complex production, companies need to prioritize safety aspects simultaneously as they develop internal processes. The addressed problem in this thesis have been centralized to the department Massamagasinet at Södra Cell in Mönsterås, mainly due to their experienced safety problems regarding forklifts and heavy vehicles. Due to the chosen context, a case study has been conducted in order to create an in-depth understanding of Södra’s witnessed safety issues. The executed thesis has been characterized by three theoretical perspectives: Multi Causational Theory, Unified Theory of Acceptance and Use of New Technology as well as Virtual Reality. Thanks to the theories, an identification of safety shortcomings as well as user requirements was made possible. The context and theoretical perspectives have consistently been linked to chosen technologies, Virtual Reality simulators and RFID. Furthermore, interviews with users as well as software-developers have provided a broader perspective, regarding the situation and techniques mentioned above. Results generated, includes both technical possibilities and limitations based on the thesis initial perspective. Moreover, it has been shown that a potential reduction of identified shortcomings is possible, by using a Virtual Reality simulator and RFID system. However, it’s worth mentioning that such implementations and the advantages they potentially might generate, are feasible first when prevailing requirements regarding the techniques are carefully considered. Investments of similar character require both human and financial resources, where maximum value can be achieved first if the employees stands positively against such implementation. Thanks to the theory Unified Theory of Acceptance and Use of New Technology, this thesis has been enriched with an additional perspective which aimed to investigate how Södra in general, and Massamagasinet in particular, stands towards new techniques.
8

Managing timber procurement in Nordic purchasing sawmills

Helstad, Klara January 2006 (has links)
Procurement of sawlogs to purchasing sawmills represents a basic strategic business process. The properties of inbound sawlogs are decisive for the output of sawn products and the cost of raw material contributes substantially to the cost of the final product. Increasing customer orientation and new demands from powerful customers in the building and retail sectors entail new or accentuated demands on management of procurement. Managing raw material procurement and communicating needs to suppliers and logging machine operators are vital issues for sawmills in order to be competitive. The purpose of the thesis is to explore how purchasing sawmills manage procurement of sawlogs. The results are based on 46 in-depth interviews with people involved in the procurement process at seven softwood sawmills in Denmark, Finland and Sweden. The thesis identifies various types of supply uncertainties as well as process improvement and buffer activities that reduce uncertainties. However, the major obstacle in the procurement process is the power/dependence balance in the relationships with suppliers. Beyond doubt, it restricts the manageability of procurement and particularly bucking. The results suggest that there are a number of ways to improve management of procurement, which are currently not fully employed. The thesis provides four key strategic dimensions of the procurement process and suggests a general conceptual model of wood procurement to purchasing sawmills. Further research within the subject can usefully explore the link between procurement management and procurement strategy as well as the relation to other functions' strategies and the corporate strategy. The importance of the identified strategic dimensions of the procurement process needs to be quantified in order to provide normative suggestions.
9

Det dolda kulturlandskapet : Okända fartygslämningar i vår närmiljö. / The hidden cultural landscape. : Unknown ship remains in our immediate environment.

Högberg, Lennarth January 2021 (has links)
Along Sweden’s east coast there are thousands of well-preserved shipwrecks after an extensive shipping that stretches far back in history. The Baltic Sea is a unique sea in the sense that the ship worm Teredo Navalis cannot live here, which means that the ship’s timber is well preserved under water. But we have little knowledge how many these wrecks are and where they are located. No comprehensive underwater inventory like those made on land has even been made. Therefore, these shipwrecks are threatened with destruction by our ignorance of them. By scanning water areas in our immediate environment with Side scan sonar technology, our state of knowledge can be significantly improved. With this method, these relics can be found and preserved as far as possible for future generations. The wrecks can also be used for recreation and experience activities.
10

Ser inte skogen för alla träd : Reducering av kvalitetsbristkostnader enligt förbättringscykeln DMAIC. En fallstudie vid Derome Timber AB / Can't see the forest for the trees : Reducing cost of quality through DMAIC. A case study at Derome Timber AB

Johansson, Erik January 2022 (has links)
Den svenska skogsindustrin är den tredje största exportören av skogsprodukter i världen och närmare 80% av produktionen exporteras. Den höga efterfrågan på svenska skogsprodukter har tillåtit det svenska sågverksföretaget Derome Timber AB att göra nyinvesteringar som resulterat i ökad produktion. Vid ett av företagets fyra sågverksanläggningar har ledningen emellertid identifierat avdelningen Justerverket som en flaskhals på grund av de stora mellanlager och kassationer som uppstått. Som följd härav vill Derome undersöka och kartlägga kvalitetsbristkostnaderna som är kopplade till avdelningen Justerverket. Tidigare studier menar att sågverksindustrin inte tillämpar systematiska förbättringsarbeten i samma utsträckning som andra industrier. Syftet med denna studie är att undersöka hur systematiska förbättringsarbeten kan tillämpas i sågverksindustrin för att arbeta med kvalitetsbristkostnader. Syftet uppfylls genom en litteraturgenomgång och ett Lean Sex Sigma (LSS) projekt vid Derome Timber AB:s avdelning Justerverket. LSS är en förbättringsstrategi som kombinerar verktyg från Lean och Sex Sigma, avsedd för att reducera kostnader och öka effektivitet. LSS-projektet följer strukturen DMAIC (Define, Measure, Analyze, Improve och Control) och genomförs med hjälp av flera kvalitetstekniska verktyg under respektive fas i förbättringscykeln. I en av studien framtagen konceptuell modell illustreras vidare hur systematiska förbättringsarbeten kan tillämpas i sågverksindustrin för att arbeta med kvalitetsbristkostnader genom LSS-verktyg och DMAIC. Merparten av fallföretagets kvalitetsbristkostnader utgörs av dolda kvalitetsbristkostnader i form av förlorade intäkter som beräknades uppgå till ca 13Mkr. Genom insamling av frekvensdata framkom det att driftstopp står för den primära orsaken till de identifierade kvalitetsbristkostnaderna. Orsaken till driftstoppen kartlades därefter genom verktygen Ishikawadiagram och 5 Varför tillsammans med sågverkets medarbetare. I denna fas framkom det att data över driftstopp och kunskap om värdet i att mäta dessa saknas. En rad rekommenderade åtgärder togs fram genom LSS-projektet och den teoretiska referensramen. Dessa inkluderar utbildning, upprättandet av arbetsrutiner och engagemang kring arbete med kvalitetsbristkostnader. Implementering av ett nytt nyckeltal, TAK (Tillgänglighet, Anläggningsutnyttjande, Kvalitetsutbyte), rekommenderas för att ge en rättvisande bild över Justerverkets faktiska prestation. Slutligen rekommenderas implementering av statistisk processtyrning (SPS) för att urskilja systematiska orsaker till driftstopp från slumpmässiga. / The Swedish forest industry is the third largest exporter of forest products in the world and almost 80% of the production is exported. The high demand for Swedish forest products has allowed the Swedish sawmill company Derome Timber AB to make new investments, resulting in an increased production. At one of the company's four sawmill facilities, however, the management has identified the Adjustment department as a bottleneck due to the large intermediate storage and rejections that have arisen. Therefore, Derome wants to investigate and identify the costs of quality linked to the Adjustment Department. However, previous studies have found that the sawmill industry does not apply systematic improvement methods to the same extent as other industries. The aim of this study is to investigate how systematic improvement methods can be applied in the sawmill industry to work with cost of quality. The aim is achieved through a brief literature review and a Lean Sex Sigma (LSS) project at Derome Timber AB's Adjustment department. LSS is an improvement strategy that combines tools from Lean and Six Sigma, designed to reduce costs and increase efficiency. The LSS project follows the structure of DMAIC (Define, Measure, Analyze, Improve and Control) and shows the use of several quality improvement tools in each phase of the improvement cycle. A conceptual model developed in the current study illustrates how systematic improvement methods can be applied in the sawmill industry to work with cost of quality through LSS and DMAIC. The vast majority of the case company's cost of quality consists of hidden costs in the form of lost income, which is estimated to approximately 13 million SEK. Through the collection of frequency data, it emerged that downtime account for the primary cause of the identified costs of quality. The cause of downtime was then mapped through the tools Ishikawa diagram and 5 whys together with the sawmill's employees. In this phase, it emerged that data on downtime and knowledge of the value in measuring it are lacking. Several recommended measures are developed through the LSS project and the theoretical frame of reference. These include training, the establishment of work routines and commitment to work with cost of quality. Implementation of a new key performance indicator, OEE (Overall Equipment Effectiveness), is recommended to provide an accurate representation of the Adjustment department’s actual performance. Finally, the implementation of statistical process control (SPC) is recommended to distinguish systematic root causes of downtime from random ones.

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