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Mechanical and chemical chip pre-treatment in mechanical pulp productionSjölin, Malin January 2008 (has links)
The mechanical pulping industry has been developing throughout the years, due to competitive prices in the electricity market and good accessibility of wood. This has made it possible for such and “expensive” process to further develop. Today, with increasing electricity prizes, it is of great interest to reduce electrical consumption in mechanical pulping industry, since the process consumes large amounts of electricity. Braviken paper mill is starting up a new thermomechanical pulping line, scheduled for start-up in August 2008, which aims to reduce electrical consumption. The new line will include chip pre-treatment equipment such as an impregnator, an Andrtiz Impressafiner (Screw press), a high intensity primary stage refines double disc (DD), and a new low consistency refiner (LC), significantly bigger than those earlier available on the market. This master´s thesis is one out of three Master´s thesis made at Braviken paper mill during spring 2008. They all are connected, and are investigating the possibility to reduce electric energy consumption within TMP production. Master´s thesis concerning high consistency refining was done by Dino Muhic, “High consistency refining of mechanical pulps during varying refining conditions”, and low consistency refining written by Fredrik Johansson “Increased energy efficiency in low consistency refining”. Chip pre-treatment is to be used to reduce electrical consumption. Mechanical pre-treatment, such as using an Andrtiz Impressafiner demolishes the chips while also making it possible to impregnate the chips with chemicals, the later giving additional possibilities to reduce electricity consumption. Chemical chip pre-treatment decreases the lignin softening temperature, which benefits the refining process, yielding longer and less damaged fibers that will create a fibrous pulp with reduced electrical energy input.The goal for this study was to investigate the effect of alkaline-peroxide on chip pre-treatment by using a design of experiment method, in terms of electric energy consumption for the process, strength properties, opacity and ISO-brightness within the pulp/sheets. The trials were built up as a factorial experiment, with two factors, alkaline and peroxide, with two levels each (high and low). The high level for alkaline was 15 kg/t and 10 kg/t for the low level, and the high level for peroxide was 10 kg/t and 5 kg/t for the low level. This resulted in four trials with two zero-points, and two reference pulps, one normal TMP, thermomechanical pulp, and the other TMP with pressafiner and water. The trials showed that adding alkaline-peroxide clearly had an impact on pulp properties, such as increased strength properties, fiber length improvements and less shives could be found in the alkaline-peroxide treated pulps. The yield was highest for the normal TMP, about 99% and it decreased with increasing alkaline addition, the lowest value was achieved for the pulps containing the highest dose of alkaline, about 95%. The optical properties were more or less as expected. Opacity had the highest value for the pulps that had been made from chips with the highest total alkaline level. The ISO brightness was highest for pulps containing low level of alkaline. It could not be decided if the electricity demand had been reduced for the chemically treated pulps; it actually had the opposite effect as expected. The chemically treated pulps demanded a higher SEC, specific energy consumption, compared to the reference pulps. This result could have depended on the small pilot plant high consistency refiners at CTP, Centre technique du papier, Grenoble, France, due to the plate size and what kind of plats that were used. To do trials like this and to be able to draw correct conclusions relevant for a full scale plant, bigger refiners might give a more comparable result. It was clear that the fiber properties had improved, which could be the key to reduce electricity when LE- (low-energy) plates are used in the HC-refiner. A higher intensity could be used and electricity energy could be saved.
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Mechanical and chemical chip pre-treatment in mechanical pulp productionSjölin, Malin January 2008 (has links)
<p> </p><p><p>The mechanical pulping industry has been developing throughout the years, due to competitive prices in the electricity market and good accessibility of wood. This has made it possible for such and “expensive” process to further develop. Today, with increasing electricity prizes, it is of great interest to reduce electrical consumption in mechanical pulping industry, since the process consumes large amounts of electricity. Braviken paper mill is starting up a new thermomechanical pulping line, scheduled for start-up in August 2008, which aims to reduce electrical consumption. The new line will include chip pre-treatment equipment such as an impregnator, an Andrtiz Impressafiner (Screw press), a high intensity primary stage refines double disc (DD), and a new low consistency refiner (LC), significantly bigger than those earlier available on the market. This master´s thesis is one out of three Master´s thesis made at Braviken paper mill during spring 2008. They all are connected, and are investigating the possibility to reduce electric energy consumption within TMP production. Master´s thesis concerning high consistency refining was done by Dino Muhic, “<em>High consistency refining of mechanical pulps during varying refining conditions</em>”, and low consistency refining written by Fredrik Johansson “I<em>ncreased energy efficiency in low consistency refining</em>”.</p><p><p>Chip pre-treatment is to be used to reduce electrical consumption. Mechanical pre-treatment, such as using an Andrtiz Impressafiner demolishes the chips while also making it possible to impregnate the chips with chemicals, the later giving additional possibilities to reduce electricity consumption. Chemical chip pre-treatment decreases the lignin softening temperature, which benefits the refining process, yielding longer and less damaged fibers that will create a fibrous pulp with reduced electrical energy input.The goal for this study was to investigate the effect of alkaline-peroxide on chip pre-treatment by using a design of experiment method, in terms of electric energy consumption for the process, strength properties, opacity and ISO-brightness within the pulp/sheets. The trials were built up as a factorial experiment, with two factors, alkaline and peroxide, with two levels each (high and low). The high level for alkaline was 15 kg/t and 10 kg/t for the low level, and the high level for peroxide was 10 kg/t and 5 kg/t for the low level. This resulted in four trials with two zero-points, and two reference pulps, one normal TMP, thermomechanical pulp, and the other TMP with pressafiner and water.</p><p>The trials showed that adding alkaline-peroxide clearly had an impact on pulp properties, such as increased strength properties, fiber length improvements and less shives could be found in the alkaline-peroxide treated pulps. The yield was highest for the normal TMP, about 99% and it decreased with increasing alkaline addition, the lowest value was achieved for the pulps containing the highest dose of alkaline, about 95%. The optical properties were more or less as expected. Opacity had the highest value for the pulps that had been made from chips with the highest total alkaline level. The ISO brightness was highest for pulps containing low level of alkaline. It could not be decided if the electricity demand had been reduced for the chemically treated pulps; it actually had the opposite effect as expected. The chemically treated pulps demanded a higher SEC, specific energy consumption, compared to the reference pulps. This result could have depended on the small pilot plant high consistency refiners at CTP, Centre technique du papier, Grenoble, France, due to the plate size and what kind of plats that were used. To do trials like this and to be able to draw correct conclusions relevant for a full scale plant, bigger refiners might give a more comparable result. It was clear that the fiber properties had improved, which could be the key to reduce electricity when LE- (low-energy) plates are used in the HC-refiner. A higher intensity could be used and electricity energy could be saved.</p></p></p>
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Vývoj aplikace pro měření spotřeby elektrické energie strojních zařízení / DAQ application development for measurement of electric energy consumption in machineryKovář, Lukáš January 2020 (has links)
The goal of the diploma thesis is to develop application for data acquisition and analysis during the measurement of electrical consumption at mechanical machines. First part of the diploma thesis is providing general summary about the methods of measuring the electrical consumption. Special focus is given on methods of the metering electrical consumption in three-phase distribution network. Furthermore, the data acquisition components are being described. Hardware components and development environment LabVIEW where the program itself was created are detailly described.
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Virtual power: um modelo de custo baseado no consumo de energia do processador por máquina virtual em nuvens IaaS / Virtual power: a cost model based on the processor energy consumption per virtual machine in IaaS cloudsHinz, Mauro 29 September 2015 (has links)
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Previous issue date: 2015-09-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The outsourcing of computing services has been through constant evolutions in the past years, due to the increase of demand for computing resources. Accordingly, data centers are the main suppliers of computing service and cloud-based computing services provide a new paradigm for the offer and consumption of these computing resources. A substantial motivator for using cloud computing is its pricing model, which enables to charge the customer only for the resources he used, thus adopting a pay-as-you-use cost model. Among cloud-based computing services, the service type Infrastructure-as-a-Service (IaaS) is the one mostly used by companies that would like to outsource their computing infrastructure. The IaaS service, in most cases, is offered through virtual machines. This paper revisits the cost models used by data centers and analyses the costs of supply of virtual machines based on IaaS. This analysis identifies that electricity represents a considerable portion of this cost and that much of the consumption comes from the use of processors in virtual machines, and that this aspect is not considered in the identified cost models. This paper describes the Virtual Power Model, a cost model based on energy consumption of the processor in cloud-based, virtual machines in IaaS. The model is based on the assumptions of energy consumption vs. processing load, among others, which are proven through experiments in a test environment of a small data center. As a result, the Virtual Power Model proves itself as a fairer pricing model for the consumed resources than the identified models. Finally, a case study is performed to compare the costs charged to a client using the cost model of Amazon for the AWS EC2 service and the same service charged using the Virtual Power Model. / A terceirização dos serviços de computação tem passado por evoluções constantes nos últimos anos em função do contínuo aumento na demanda por recursos computacionais. Neste sentido, os data centers são os principais fornecedores de serviço de computação e os serviços de computação em nuvem proporcionam um novo paradigma na oferta e consumo desses recursos computacionais. Um considerável motivador do uso das nuvens computacionais é o seu modelo de tarifação que possibilita a cobrança do cliente somente dos recursos que ele utilizou, adotando um modelo de custo do tipo pay-as-you-use. Dentre os serviços de computação em nuvem, o serviço do tipo IaaS (Infrastructure-as-a-Service) é um dos mais utilizados por empresas que desejam terceirizar a sua infraestrutura computacional. O serviço de IaaS, na grande maioria dos casos, é ofertado através de instâncias de máquinas virtuais. O presente trabalho revisita os modelos de custos empregados em data centers analisando a formação dos custos no fornecimento de máquina virtuais em nuvens baseadas em IaaS. Com base nesta análise identificasse que a energia elétrica possui uma parcela considerável deste custo e que boa parte deste consumo é proveniente do uso de processadores pelas máquinas virtuais, e que esse aspecto não é considerado nos modelos de custos identificados. Este trabalho descreve o Modelo Virtual Power, um modelo de custo baseado no consumo de energia do processador por máquina virtual em nuvens IaaS. A constituição do modelo está baseada nas premissas de consumo de energia vs. carga de processamento, entre outros, que são comprovados através de experimentação em um ambiente de testes em um data center de pequeno porte. Como resultado o Modelo Virtual Power mostra-se mais justo na precificação dos recursos consumidos do que os modelos identificados. Por fim, é realizado um estudo de caso comparando os custos tarifado a um cliente empregando o modelo de custo da Amazon no serviço AWS EC2 e o mesmo serviço tarifado utilizando o Modelo Virtual Power.
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Gestion autonomique de performance, d'énergie et de qualité de service : Application aux réseaux filaires, réseaux de capteurs et grilles de calcul / Autonomic management of performance, energy consumption and quality of service : Application to wired networks, sensors networks and grid computing facilitiesSharrock, Rémi 08 December 2010 (has links)
La motivation principale de cette thèse est de faire face à l'accroissement de la complexité des systèmes informatiques, qui, dans un futur proche ( de l'ordre de quelques années) risque fort d'être le principal frein à leur évolution et à leur développement. Aujourd'hui la tendance s'inverse et le coût de gestion humaine dépasse le coût des infrastructures matérielles et logicielles. De plus, l'administration manuelle de grands systèmes (applications distribuées, réseaux de capteurs, équipements réseaux) est non seulement lente mais aussi sujette à de nombreuses erreurs humaines. Un des domaines de recherche émergent est celui de l'informatique autonomique qui a pour but de rendre ces systèmes auto-gérés. Nous proposons une approche qui permet de décrire des politiques de gestion autonomiques de haut niveau. Ces politiques permettent au système d'assurer quatre propriétés fondamentales de l'auto-gestion: l'auto-guérison, l'auto-configuration, l'auto-protection et l'auto-optimisation. Nos contributions portent sur la spécification de diagrammes de description de politiques de gestion autonomiques appelés (S)PDD "(Sensor) Policy Description Diagrams". Ces diagrammes sont implémentés dans le gestionnaire autonomique TUNe et l'approche a été validée sur de nombreux systèmes: simulation électromagnétique répartie sur grille de calcul, réseaux de capteurs SunSPOT, répartiteur de calcul DIET. Une deuxième partie présente une modélisation mathématique de l’auto-optimisation pour un « datacenter ». Nous introduisons un problème de minimisation d’un critère intégrant d’une part la consommation électrique des équipements du réseau du « datacenter » et d’autre part la qualité de service des applications déployées sur le « datacenter ». Une heuristique permet de prendre en compte les contraintes dues aux fonctions de routage utilisées. / The main challenge of this thesis is to cope with the growing complexity of IT systems. In a near future (mainly the next few years) this complexity will prevent new developments and system evolutions. Today the trend is reversing and the managing costs are overtaking the hardware and software costs. Moreover, the manual administration of large systems (distributed applications, sensor networks, and network equipment) is not only slow but error-prone. An emerging research field called autonomic computing tries to bring up self-managed systems. We introduce an approach that enable the description of high level autonomic management policies. These policies allow the system to ensure four fundamental properties for self-management: self-healing, self-self-configuring, self-protecting and self-optimizing. We specify autonomic management Policy Description Diagrams (PDD) and implement them in Toulouse University Network (TUNe). We validated our approach on many systems: electromagnetic simulations distributed on computer grids (grid’5000), wireless sensor networks with SunSPOTs and the computing scheduler DIET. A second part of this thesis presents a mathematical modeling for self-optimizing datacenters. We introduce a minimization problem with a criterion integrating both the electrical consumption of the datacenter networking equipment and the quality of service of the deployed applications. A heuristic takes into account the routing functions used on the network.
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