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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.
21

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.
22

Konstruktion av skyddshuv för röntgenrör till RemaLog X-Ray

Nordin, Daniel January 2013 (has links)
Denna rapport kommer av avhandla det examensarbete som genomförts inom civilingenjörsprogrammet innovation och produktdesign på Mälardalens högskola. Arbetet har genomförts på RemaControl Sweden AB och startade den 3:e september 2012 med slutpresentation den 29:e mars 2013. RemaControl är ett företag som är baserat i Västerås och tillverkar mätsystem till sågverksindustrin. Den produkt som detta projekt har kretsat runt är deras mätsystem som heter RemaLog X-Ray som är ett ”state-of-the-art-system” som använder sig av röntgen för att läsa av mätdata från trästockar när de kommer in på sågverket. Uppdraget från RemaControl var att omkonstruera den skyddshuv som omsluter röntgenrören. Dess syfte är att skydda miljön utanför mätramen från strålning som röntgenrören genererar. Röntgenrören måste servas vart 6:e månad och för att komma åt röntgenrören så måste man i dagsläget montera bort skyddsramen. Detta är ett moment som tar tid och är slitsamt för servicepersonalens ryggar eftersom den är svåråtkomlig och väger över 25 kg. Anledningen till dess höga vikt är på grund av att den måste vara tillverkad med blyväggar för att stoppa strålningen. Det är även viktigt för sågverken att servicetiden är så kort som möjligt eftersom det minskar tiden som banan behöver stå still, i vilket sågverken förlorar pengar. För att lösa detta problem så har uppdraget delats upp i olika delproblem som har lösts på olika sätt. Det har tagits fram olika koncept med hjälp av CAD. Dessa koncept har utvärderats och en helhetslösning har tagits fram som uppfyller RemaControls krav. Utöver detta så har även en prototyp tagits fram för att säkerställa att dess egenskaper uppfyller även alla krav i praktiken. / This report contains the thesis work in the civil engineering program of innovation and product design on Mälardalens Högskola, Sweden. This work has been collaboration with RemaControl Sweden AB and it started on September the 5th 2012 and was presented on April the 5th 2013. RemaControl is a company that is based in Västerås, Sweden, and manufactures measuring systems for the sawmill industry. This project has been focused on their system RemaLog XRay that is a state-of-the-art-system that implements x-ray-technology to retrieve measuring data from incoming logs of wood. The assignment from RemaControl was to redesign the protective housing that contains the xray tubes. Its purpose is to protect the outside environment from radiation generated from the x-ray tubes. The x-ray tube needs to be maintained every 6 thmonths and to retrieve the x-ray tubes it is necessary to remove the protective housing in its present configuration. This operation puts the service engineers backs in unfavorable positions because it is very inaccessible to retrieve and has a weight of more than 25 kg. The reason for this weight is because that the protective housing needs to be constructed with walls of pure lead to protect the outside environment from the radiation. It is also important for sawmills that the time of the service is as short as possible because it prevents interruption of the runway, from which sawmills loses money. To solve this assignment the problem has been divided into sub problems that have been solved with different methods. Different concept solutions have been creating using CAD. These concepts have been evaluated and a final solution has been created that meets the requirement from RemaControl. To ensure that its practical properties are sufficient, a prototype has also been developed.
23

Att skolas för hemmet : trädgårdsskötsel, slöjd, huslig ekonomi och nykterhetsundervisning i den svenska folkskolan 1842-1919 med exempel från Sköns församling / Schoolin for the home : gardening, handicraft, domestic science and temperance instruction in Swedish elementary school 1842-1919 with an example from the parish of Skön

Johansson, Ulla January 1987 (has links)
This study deals with how the subjects Gardening, Handicraft, Domestic Science and Temperance Instruction were introduced and developed in elementary school (compulsory school) in Sweden during the period 1842-1919. During this same period a capitalist mode of production replaced the feudal one with consequent changes in home life for the people. The school subjects dealt with have been selected to throw light on whether and to what extent the elementary school was used to bring about a reorganization in the lives of wage earner families.The official argument, curricula and school enquiries have been examined. Teaching content in relation to workers' family conditions has been studied in the parish of Skön in the sawmill region of northern Sweden.The main official argument was that the miserable conditions of working class life were caused just as much by ignorant housewives and drunken fathers as by low wages and poor housing. The cure was therefore seen to lie in education, and the introduction of the subjects in question can be seen in the light of this.The study shows how the state gradually took over more and more of the responsibility for child upbringing, and how the schools of the sawmill companies played a part in this process. The results, however, indicate that the actual effect of elementary school teaching on the home lives of sawmill workers was insignificant. Working class poverty was ol course caused primarily by economic and structural factors, but defining the problems in pedagogical terms meant that responsibility could be apportioned at an individual level - and thereby the bourgeoisie reaped considerable ideological profits.Key word: history of education, Swedish compulsory school, Gardening, Handicraft, Domestic Science, Temperance Instruction, working class family, sawmill region. / digitalisering@umu
24

Statistical Process Control for the Sawmill Industry / Statistisk processkontroll för sågverksindustrin

Sundholm, Per January 2015 (has links)
In the sawmill industry, it can be very profitable to monitor the dimensions of sawn boards so that operators quickly can detect errors and take cor-rective action. In this master’s thesis project, Statistical Process Control (SPC) methods have been implemented to achieve this. SPC is a set of statistical methods whose purpose is to minimize the variations in an in-dustrial process. In particular, the SPC method used here is the control chart, which with an upper and lower control limit quantifies the bounds of natural variation. To find the most suitable control chart, five control charts monitoring the process mean, and two monitoring process variability were tested with help of both a simulation study and an empirical evaluation. The result of the evaluation was that the ”Average Moving Range” chart was regarded the most suitable for changes in process mean, and the Range chart was regarded as the best at detecting changes in process variability. Both charts are constructed for individual boards and not subgroups of boards (as is more common) due to compatibility reasons with the existing measurement practice. The two methods were deemed to be quite able to detect process changes, but some results indicate that the methods might work better for double arbour saw lines than single arbour ones. / Det kan vara mycket lönsamt för sågverk att övervaka mått på plankor så att personal snabbt kan hitta och åtgärda fel som uppstår i processen. I det syftet har det här masterarbetet gått ut på att implementera statistisk processkontroll (SPC) för råmåttkontroll på sågverk. SPC är en mängd olika statistiska metoder vars syfte är att minimera spridningen i en tillverkningsprocess. Den metod som är i speciellt focus i det här arbetet är det så kallade styrdiagrammet som med en övre och undre gräns kvantifierar hur stor den naturligt förekommande spridningen är. För att finna det mest lämpade styrdiagrammet utvärderades fem styrdiagram som övervakar processens medelvärde och två styrdiagram som övervakar processens spridning. Denna utvärdering bestod både av en simuleringsstudie och tester gjorda för empiriskt data. Utvärderingen resulterade i att det så kallade ”Average Moving Range” diagrammet rekommenderades för övervakning av medelvärde och ett räckviddsstyrdiagram rekommenderades för spridningen. Båda styrdiagrammen konstruerades för enskilda plankor och inte för stickprov av flera plankor (vilket är vanligare) på grund av kompatibelitetsskäl med gängse mätmetodik. De båda metoderna ansågs vara ganska bra på att upptäcka processförändringar men vissa resultat tyder på att metoderna kanske fungerar bättre för sågverk med mötande klingor än enaxliga sågverk.
25

Investigation into the use of meta-heuristics in the optimisation of log positioning during sawmill processing

Du Plessis, Johan de Villiers 12 1900 (has links)
Thesis (MSc (Forest and Wood Science))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The percentage yield of sawn timber recovered from logs has a large influence on the profitability of a sawmill. The positioning of the log as it is fed into the primary breakdown saw is one of the factors that impacts on the volume recovery percentage. The log’s position can be adjusted by changes in rotation, offset and skewness and depending on the ranges and increments used for these variables, the number of possible combinations can become substantial. In a sawmill the time available to assess possible log positions is limited and different strategies can be followed to arrive at an optimal or close‐to‐optimal positioning solution without an exhaustive evaluation of solutions. Meta‐heuristics are sometimes used to arrive at solutions for combinatorial optimisation problems in a limited time. The effectiveness of this approach on the optimisation of timber volume recovery based on log form is evaluated in this study using sawmill simulation data of sixty SA pine logs. A new meta‐heuristic, for convenience named the Tentacle algorithm, was developed specifically for the problem of log positioning optimisation. The results obtained with the Tentacle algorithm was compared with results from three existing meta‐heuristics i.e. the Simulated Annealing algorithm, the Population Based Incremental Learning algorithm and the Particle Swarm Optimisation algorithm, in terms of its efficiency and effectiveness in finding good log positioning solutions in a limited time. A fifth method, that of exhaustively searching smaller, high quality areas around the centered and “horns‐up” and “horns‐down” positions in the search space was compared to that of using the meta‐heuristic algorithms. In terms of volume recovery, the Tentacle algorithm performed, on average, the best of the four algorithms evaluated. However, exhaustive searches in the smaller, high quality areas in the search space, outperformed the algorithms. / AFRIKAANSE OPSOMMING: Die herwinningspersentasie van gesaagde planke uit saagblokke het ‘n groot invloed op die winsgewendheid van ‘n saagmeul. Die posisionering van die blok in die primêre saag is een van die faktore wat die herwinningspersentasie beïnvloed. Die blok se posisie kan verstel word deur veranderinge in rotasie, oplyning en skeefheid. Afhangend van die veld ‐en inkrementgrootte kan die hoeveelheid moontlike kombinasies beduidend wees. In ‘n tipiese saagmeul is die beskikbare tyd om moontlike posisies te evalueer beperk en verskeie strategieë kan gevolg word om optimale of nabyoptimale kombinasies te bereik sonder om alle moontlike kombinasies te evalueer. Meta‐heuristieke word soms gebruik om in ‘n beperkte tyd oplossings te vind vir kombinatoriese optimeringsprobleme. Die doeltreffendheid van hierdie metode by die optimering van herwinningspersentasie gebaseer op blokvorm is in hierdie studie ondersoek. Dit is met behulp van saagmeulsimulasiedata soos van sestig SA dennehoutblokke verkry, uitgevoer. ‘n Nuwe meta‐heuristiek, genaamd die Tentakelalgoritme, is tydens hierdie studie spesifiek vir die probleem van blokposisie‐optimering ontwikkel. Die resultate verkry met die Tentakelalgoritme is vergelyk met drie bestaande meta‐heuristieke, nl. die “Simulated Annealing”‐algoritme, die “Population Based Incremental Learning”‐algoritme en die “Particle Swarm Optimisation”‐algoritme in terme van doeltreffendheid om goeie blokposisies in ‘n beperkte tyd te vind. ‘n Vyfde metode, die gebruik van ‘n volledige ondersoek van verkleinde versamelings, rondom hoë‐kwaliteit areas in die soekarea, is vergelyk met die gebruik van die meta‐heuristieke. Hierdie hoë‐kwaliteit areas word gevind rondom die gesentreerde “horns‐up” en “horns‐down” posisies. Die Tentakelalgoritme het gemiddelde die beste herwinningsresultate van die vier meta‐heuristieke wat ondersoek was gelewer. Die volledige ondersoek van verkleinde versamelings in die hoë kwaliteit areas het egter die meta‐heuristieke oortref.
26

Monitoramento da deflexão de serras de fita contínua como proposta de avaliação da qualidade de peças serradas de madeira /

Gehring Junior, Waldemar. January 2016 (has links)
Orientador: Marcos Valério Ribeiro / Coorientador: Marcos Tadeu Tibúrcio Gonçalves / Banca: Manoel Cleber Sampaio Alves / Banca: José Vitor Candido de Souza / Banca: José Orlando Gomes / Banca: Carlos de Oliveira Affonso / Resumo: No serramento contínuo da madeira por serra de fita, o projeto da ferramenta de corte, o desgaste e as avarias do uso destas ferramentas no processo de produção fazem com que o comportamento da lâmina ao longo de um ciclo de uso seja mais ou menos instável, podendo perder estabilidade e impactando em produtos mal serrados. Conhecer essa tendência ao longo de toda a vida útil da serra ou mesmo a sua aplicação em dado período em condições reais de corte permite avaliar o projeto da serra e sua durabilidade. Para isso, o projeto de um dispositivo robusto, resistente a vibração e a ambientes severos e sujos, além de boa capacidade de armazenamento de informações é de grande valia. O objetivo do presente trabalho foi propor um dispositivo de registro de dados para monitorar a instabilidade/vibração da ferramenta de corte no processo de serramento da madeira por serra de fita. Com vistas a essas premissas foram estudados os elementos para o projeto da ferramenta de corte e as referências sobre os fundamentos da usinagem da madeira, o projeto da ferramenta de corte, sua geometria e causas para as decorrências como a vibração, estabilidade e desgaste. Foi construído um protótipo em escala laboratorial, onde foi validado o pré-projeto e o sistema de aquisição de dados. Optou-se pelo uso do microcontrolador Arduino que disponibiliza software livre para sua programação permitindo que o sistema possa ser reproduzido a baixo custo. Em um segundo estágio este mecanismo de controle foi exp... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In continuous sawing wood by a large Bandsaw the cutting tool design, use and tools faults in the production process causes blade behavior over a duty cycle. The process looses stability and impacts in badly sawn products. Knowing this trend throughout the life of the blade or its application in a given period on real conditions of cut allows evaluating the project and the durability of the saw. For this, the design of a robust device, resistant to vibration, harsh and dirty environments and good information storage capacity is a big deal. The aim of this study was to propose a data recording device to monitor the instability / vibration of the cutting tool in Bandsawing process of the wood. With a view to these assumptions were studied elements for cutting tool design and references about the fundaments of wood machining, cutting tool design, geometry and the causes that origin vibration, instability and tools wear. A prototype in laboratory scale which has validated the pre-design and data acquisition system was built. We chose to use the Arduino microcontroller that provides free software to its programming allowing the system to be reproduced at low cost too. In a second stage this control mechanism has been expanded to a timber industrial environment where it might be used as support for the evaluation of the cutting process. The device proved to be robust and operational in real production conditions in a large sawmill. This paper reports the used sensor, microcontrolle... (Complete abstract click electronic access below) / Résumé: Dans le sciage continu de bois effectué avec une scie à ruban, la conception de l'outil de coupe, l'usure et les dommages dus à l'utilisation de cet outil dans le processus de production modifient le comportement de la lame sur un cycle d'utilisation, la rendant plus ou moins instable jusqu'à perdre sa stabilité, ce qui va générer des produits sciés de mauvaise qualité. Considérer cette tendance tout au long de la vie de la scie ou de son application dans une période donnée dans des conditions réelles de coupe permet d'évaluer et projeter la scie ainsi que sa durabilité. Pour cela, la conception d'un dispositif robuste, résistant aux vibrations, aux environnements agressifs, à la saleté, tout en ayant une bonne capacité de stockage de l'information est primordiale. Le but de cette étude est de proposer un dispositif d'enregistrement de données pour surveiller l'instabilité et vibration de l'outil de coupe dans le processus de sciage du bois par scie à ruban en continu. A partir de ce scénario, les éléments du projet d'outil de coupe ont été étudiés avec pour bases l'usinage du bois, le projet de l'outil de coupe, sa géométrie et ses conséquences comme la vibration, la stabilité et l'usure. Un prototype à l'échelle de laboratoire a validé le système du préprojet et la construction de l'acquisition de données. Nous avons choisi d'utiliser le microcontrôleur Arduino qui fournit des logiciels libres de programmation permettant au système d'être fabriqué à faible coût. Dans une ... (Résumé complet accès életronique ci-dessous) / Doutor
27

Oclusão da casca indica o início da formação de clear em árvores desramadas / Bark wound occlusion indicates clear wood formation in pruned trees

Julia Carolina Araujo Fideles 31 October 2016 (has links)
O eucalipto é um gênero amplamente cultivado no Brasil desde o início do século XX. É utilizado principalmente na produção de carvão e polpa, apesar da aptidão para produção de toras para serraria. Para as espécies cultivadas no Brasil, as técnicas de manejo para serraria foram pouco desenvolvidas e delas depende a introdução efetiva da madeira serrada de eucalipto no mercado. O presente estudo objetivou identificar as variáveis do manejo florestal do Eucalyptus urophylla que determinam, física e temporalmente, a formação de madeira limpa (clear) em árvores manejadas para serraria. O experimento foi implantado em julho de 2013 na Estação Experimental de Ciências Florestais de Itatinga (E.E.C.F.I/ESALQ/USP) e consistiu de 4 espaçamentos, sendo eles (3 x 1), (3 x 2), (3 x 3) e (6 x 1,5) m. Realizou-se o primeiro inventário em janeiro de 2015, aos 18 meses de idade, com medições de atributos das árvores e dos galhos. As parcelas foram subdivididas pela metade e, também em janeiro de 2015, aplicou-se a desrama artificial (poda) até os 2,5 m do tronco em uma de cada par de subparcelas. Daí em diante foram realizadas medições de cicatrizes e incremento secundário (dendrômetros) tomadas periodicamente até fevereiro de 2016, aos 31 meses de idade. Em junho de 2015 foi feita a primeira amostragem destrutiva de toras para medição de espessura da casca e em fevereiro de 2016 uma segunda leva de toras foi amostrada e submetida a análise em laboratório. Esta amostragem não incluiu o tratamento sem poda devido à ausência de desrama natural. Toretes foram gradualmente processados em torno mecânico para observação em plano tangencial da madeira formada após a desrama artificial. Nesta etapa também mediu-se a espessura da zona de oclusão e de madeira clear. A zona de oclusão é essencialmente composta pelo exsudado secretado para proteção periférica da cicatriz na casca. A área calculada do anel de oclusão está altamente correlacionada à área do anel da casca. Portanto, a espessura da casca determina a espessura do anel de oclusão e a formação de clear se inicia quando o xilema secundário sobrepõe o ponto mais externo no plano tangencial marcado pelo exsudado. / Eucalyptus is a genus widely grown in Brazil since the beginning of the 20th century, traditionally used to produce fuel and pulp despite its potential for sawlog production. The silvicultural techniques developed for eucalyptus short rotation woody crops in Brazil have neglected essential traits for high quality sawlog production, without which eucalyptus solid wood is not marketable. The aim of the present study was to identify the variables in silvicultural management of Eucalyptus urophylla limiting, physical and temporally, clear wood formation. The experiment was established in July 2013 at the Itatinga Experimental Station, College of Agriculture \"Luiz de Queiroz\" (ESALQ), University of São Paulo (USP), Brazil, consisting of spacing trials of (3 x 1), (3 x 2), (3 x 3) e (6 x 1,5) m. Measurements o trees and branches attributes were first taken in January 2015, when trees were 18 months old. The plots were split in half (subdivided) and one of the subplots was addressed for a pruning trial in which all live and dead branches were removed to 2,5 m, also in January 2015From then on, wound occlusion and secondary growth (band dendrometers) were periodically measured until February 2016, when the trees were 31 months old. Destructive samplings were firstly carried out in June 2015, for bark thickness determination, and secondly in February 2016. The latter did not include unpruned subplots, once the trees had not yet shed the branches. Logs were debarked and processed in mechanical lathe while measurements of clear wood and occlusion zone were taken in the tangential plane. High correlation between occlusion zone ring area and bark ring area has been found. The occlusion zone of Eucalyptus urophylla is mainly composed by the exudate released by trees during the bark wound closure process. Therefore, the bark thickness establishes the occlusion ring thickness and clear wood formation starts after the secondary xylem overlaps the most external point in the tangential plane marked by the exudate.
28

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.
29

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
30

Varför steg träpriserna under 2020 och 2021? : Vad låg bakom materialbristen och de stigande priserna?

Johansson, Simon January 2022 (has links)
Trä har sedan länge varit ett av de viktigaste materialen vid husbyggnad i Sverige, mycket med tanke på den goda tillgång vi har på trävaror tack vare våra stora skogsytor. Men under 2020 och 2021 hände någonting på trämarknaden som gjorde att tillgången plötsligt inte var så stor längre, utan vi hamnade i en situation med brist i stället. Den här rapporten undersöker just den träbrist som uppstod 2020 och låg till grund för de stora prisökningar som upplevdes under åren 2020 och 2021. Vad var orsaken till dessa, och var någonstans i produktionskedjan uppstod problemen? För att ta reda på detta har undersökningsmetoden i rapporten bestått utav faktainsamling via de skrifter som redan publicerats, samt intervjuer med individer aktuella inom området. Det har intervjuats försäljningschefer på sågverk, säljare inom byggvaruhandelsektorn, samt personer verksamma i byggbolag. Intervjuer har skett i alla delar av marknadskedjan för att på så sätt kunna klargöra de olika aktörernas olika syn på problemet. Det resultat som rapporten presenterar är att coronapandemin var en starkt bidragande faktor till att efterfrågan på trävaror steg rekordartat. Många privatpersoner tvingades stanna hemma och tog då tillfället i akt att renovera och påbörja byggprojekt hemma. Även företag som drabbades hårt av pandemin och dess restriktioner, passade på att renovera och bygga om lokaler under tiden eftersom folk inte besökte dem på grund av restriktionerna. Denna kraftiga ökning i efterfrågan innebar ett stort tryck på sågverken som inte alls hann med att producera i den takt som de sålde. Detta resulterade i att sågverkens lager blev allt tunnare, och priserna steg allt mer. Rapporten beskriver även hur marknadsstrukturen för trävaror ser ut, och analyserar med hjälp av porters femkraftsmodell hur situationen ser ut. Slutsatserna blir då att marknaden är oerhört sårbar i och med den makt som sågverken sitter på, vilket blir speciellt märkbart under 2020 och 2021 då sågverken befann sig i en situation där allt de producerade blev sålt, och därmed kunde sätta vilka priser som helst. Vidare har trämarknaden en struktur som innebär att kunderna är låsta till sågverken och helt beroende av den prisnivå som de själva beslutar om. Sågverkens förhandlingssituation, brist på substitut till trä, brist på konkurrens av både befintliga och nya aktörer är alla faktorer som i allra högsta grad har påverkat och bidragit till den situation somupplevdes under åren 2020 och 2021. / Timber has been one of high importance when building houses in Sweden, due to the big supply generated by our large forest areas. But in 2020 and 2021we ended up in a situation with a shortage. This report examines the wood shortage that occurred in 2020 and was the foundation of the large price increases experienced in 2020 and 2021, causesand where problems arose in the supply chain? Previous findings was studied as well as interviews with individuals from the field, active in all parts of the market chain Findings state that the corona pandemic was a strong contributing factor to the record rise in demand for wood products resulting in s private and public projects to renovate and rebuild premises. This sharp increase in demand put pressure on the sawmills who were not able to produce at the rate they were selling. This resulted in prices rising more and more. The report also describes the market structure for wood products with Porter's five forces model. The market is extremely vulnerable due to the power that the sawmills have, accentuated by the situation in 2020 and 2021.

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