• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 20
  • 10
  • 5
  • 1
  • Tagged with
  • 40
  • 40
  • 12
  • 11
  • 9
  • 9
  • 8
  • 6
  • 6
  • 6
  • 6
  • 5
  • 5
  • 5
  • 5
  • 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

Improved pipe support design for the process industry to reduce mechanical loads on pumps / Vidareutveckling av rörstöd för processindustrin för att reducera mekaniska krafter på pumpar

Påhlsson, Carl January 2016 (has links)
This master thesis has been written to develop a new pipe support for pipe systems in the process industry. The purpose was to relieve pumps or other sensitive equipment from elevated forces or moments that may cause failure. The elevated forces or moments occur due to the weight of the piping, the weight of the medium and expansion due to elevated temperatures. The support is mainly designed to be implemented in a 90 degree bend but they can also be implemented in straight pipes with small adjustments of the attachment between the support and the pipe. Six different complete concepts were developed and put through different elimination matrices and evaluated against a requirement specification. The final design was calculated to withstand the forces and moments from a worst case scenario. The concept is in need of further development and testing before it can be implemented in projects. It is necessary to investigate if the clamps can withstand the working load in the new design. The concept should also be tested possibly by a prototype.
2

Optimization of Burner Kiln7, Cementa Slite

Grönwall, Fred January 2010 (has links)
Abstract   The fuel is put into the process through a burner pipe and this burner pipe is modified to reach a more efficient combustion. The primary target is to enable burning of heterogeneous alternative fuels and increase the production level. Other positive effects from this type of optimization is lowered specific fuel consumption and lowered CO2 emissions. A redundant burner is chosen for the project and overall the project steps are the following: 1. Installing a Jet air nozzle ring in a way so it can move both axially and radially due to temperature changes. 2. Remove the present refractory from the burner and order a new form to decrease the weight of the burner 3. Place a K6 blower in operating the axial channel. 4. Install Gauging equipment (Temp, pressure, ampere blower etc) 5. Carefully observe process values during the modified burners run in time. 6. Evaluate the results of the project 7. With the help of proven potential in the kiln system be able to convince management of the proceeds to invest in a new burner 8. If point 7 is fulfilled with the help of experience, be able to operate as a projectcoordinator in the purchase of a professional burner. This task will include coordinating the project group in various meetings and then lead to an RFQ (Request For Quotation). Results from the project show the great potential in an optimization of a burner at a cement plant. A production increase of 5% could be seen together with a lowered specific energy consumption which is extremely satisfactory results. Unfortunately a breakdown of the system occurred a bit down the path of optimisation that resulted in damages to the kiln. At this stage the optimization was stopped and the old burner was put back after finished kiln repair. Finally crucial to underline is that the proven results in this study convinced the Group Management of buying a new burner. The benefits from a professional tailor made burner are far greater than the cost of buying it. The payback time is roughly around a year for such an investment depending on current market conditions. In this report focus is put on the combustion process at a cement plant. Combustion is the heart of the cement making process and absolutely crucial to have under full control and well optimized.
3

Fluid property reasoning in knowledge-based hazard identification

Heino, Perttu M. January 1998 (has links)
The study of serious accidents, which have occurred in the chemical process industry in recent times, highlights the need to understand fluid property related phenomena and the interactions between chemicals under abnormal process conditions or with abnormal fluid compositions. Consideration of these issues should be common practice in professional safety analysis work, and computer programs designed to support this work have to be able to deal with them.
4

Modelos matemáticos para problemas de planejamento da produção em indústrias de processos / Mathematical models for production planning problems in process industries

Cunha, Artur Lovato da 09 November 2018 (has links)
Nesta tese é realizado um estudo de caso em uma indústria química brasileira, no qual busca-se representar características da tomada de decisões para a programação da produção em plantas de bateladas. Para isso, foi proposto um modelo matemático do tipo MIP (Mixed Integer Programming) que considerou a disponibilidade de matérias-primas, múltiplas tarefas produtivas para um mesmo produto, tanques de armazenamento multiproduto, envase de produtos e demanda de produtos a granel e envasados. O objetivo principal desse estudo era permitir a obtenção de soluções compatíveis com a prática da empresa em tempo de processamento viável. A partir desse estudo de caso, foi efetuado um segundo estudo com objetivo de avaliar o desempenho de formulações matemáticas para a resolução de um problema de programação da produção. Foram considerados modelos clássicos das comunidades científicas de pesquisa operacional e de engenharia de sistemas de processo, além de um terceiro modelo desenvolvido a partir de conceitos dessas duas comunidades. Algumas características do estudo de caso não foram retratadas, como o consumo de matérias-primas e o envase dos produtos, porém, foram consideradas duas características comumente observadas em problemas da indústria de processos: bateladas com quantidade produzida flexível e tarefas que produzem mais de um produto. Por fim, um terceiro estudo foi realizado com base no estudo de caso da indústria química brasileira, porém, com um foco decisões mais próximas ao nível tático. Sendo assim, foi considerado apenas o dimensionamento de lotes, sem o sequenciamento da produção. Por outro lado, foram acrescentadas características pertinentes à aquisição de matérias-primas, como custos das matérias-primas e descontos por quantidade adquirida. O objetivo deste último trabalho era avaliar a influência da integração das decisões de dimensionamento de lotes e de aquisição das matérias-primas nos custos da cadeia produtiva durante todo o horizonte de planejamento. / In this thesis we developed a study case in a Brazilian chemical industry, in which the aim was to represent the characteristics of decision-making for production scheduling in batch plants. For this, a mixed integer programming model was proposed to consider the availability of raw materials, multiple productive tasks for the same product, multi-product storage tanks, product packaging and demand for products in bulk and packaged. The main objective of this study was develop a model that is able to obtain solutions that clould be used in practice for this chemical industry in viable processing time. From this study case, a second work was carried out to evaluate the performance of mathematical formulations to solve a problem of production scheduling. Classic models of operational research and process system engineering communities were considered, and a third model was developed from concepts of these two communities. Some features of the case study were not modelled, such as the consumption of raw materials and the product packaging, however, two characteristics usually present in process industries were considered: flexible batch production quantity and multi-product task production. Finally, a third study developed based on the study case of the Brazilian chemical industry, but with focus on decisions more familiar to the tactical level. Thus, only lot sizing was modelled, without production scheduling. On the other hand, features relevant raw material purchasing were included, such as raw material costs and discounts for quantity purchased. The objective of this last work was to evaluate the influence of integrating lot sizing decisions and raw material purchasing decisions in the overall costs of the production chain during the entire planning horizon.
5

Modelos matemáticos para problemas de planejamento da produção em indústrias de processos / Mathematical models for production planning problems in process industries

Artur Lovato da Cunha 09 November 2018 (has links)
Nesta tese é realizado um estudo de caso em uma indústria química brasileira, no qual busca-se representar características da tomada de decisões para a programação da produção em plantas de bateladas. Para isso, foi proposto um modelo matemático do tipo MIP (Mixed Integer Programming) que considerou a disponibilidade de matérias-primas, múltiplas tarefas produtivas para um mesmo produto, tanques de armazenamento multiproduto, envase de produtos e demanda de produtos a granel e envasados. O objetivo principal desse estudo era permitir a obtenção de soluções compatíveis com a prática da empresa em tempo de processamento viável. A partir desse estudo de caso, foi efetuado um segundo estudo com objetivo de avaliar o desempenho de formulações matemáticas para a resolução de um problema de programação da produção. Foram considerados modelos clássicos das comunidades científicas de pesquisa operacional e de engenharia de sistemas de processo, além de um terceiro modelo desenvolvido a partir de conceitos dessas duas comunidades. Algumas características do estudo de caso não foram retratadas, como o consumo de matérias-primas e o envase dos produtos, porém, foram consideradas duas características comumente observadas em problemas da indústria de processos: bateladas com quantidade produzida flexível e tarefas que produzem mais de um produto. Por fim, um terceiro estudo foi realizado com base no estudo de caso da indústria química brasileira, porém, com um foco decisões mais próximas ao nível tático. Sendo assim, foi considerado apenas o dimensionamento de lotes, sem o sequenciamento da produção. Por outro lado, foram acrescentadas características pertinentes à aquisição de matérias-primas, como custos das matérias-primas e descontos por quantidade adquirida. O objetivo deste último trabalho era avaliar a influência da integração das decisões de dimensionamento de lotes e de aquisição das matérias-primas nos custos da cadeia produtiva durante todo o horizonte de planejamento. / In this thesis we developed a study case in a Brazilian chemical industry, in which the aim was to represent the characteristics of decision-making for production scheduling in batch plants. For this, a mixed integer programming model was proposed to consider the availability of raw materials, multiple productive tasks for the same product, multi-product storage tanks, product packaging and demand for products in bulk and packaged. The main objective of this study was develop a model that is able to obtain solutions that clould be used in practice for this chemical industry in viable processing time. From this study case, a second work was carried out to evaluate the performance of mathematical formulations to solve a problem of production scheduling. Classic models of operational research and process system engineering communities were considered, and a third model was developed from concepts of these two communities. Some features of the case study were not modelled, such as the consumption of raw materials and the product packaging, however, two characteristics usually present in process industries were considered: flexible batch production quantity and multi-product task production. Finally, a third study developed based on the study case of the Brazilian chemical industry, but with focus on decisions more familiar to the tactical level. Thus, only lot sizing was modelled, without production scheduling. On the other hand, features relevant raw material purchasing were included, such as raw material costs and discounts for quantity purchased. The objective of this last work was to evaluate the influence of integrating lot sizing decisions and raw material purchasing decisions in the overall costs of the production chain during the entire planning horizon.
6

Estudo da readequação estratégica e de operações no setor de não tecidos

Fasolo, Ricardo Basso January 2010 (has links)
Este trabalho tem como objetivo o estudo da readequação estratégica e operacional no segmento de nãotecidos, pertencente à terceira geração da cadeia petroquímica, frente à realidade global das consolidações por parte de fornecedores e clientes. Este setor caracterizase por ser intensivo em capital e possuir fluxos contínuos de produção com a geração intrínseca de resíduo como subproduto de seu processo produtivo. Baseando-se em referências sobre gestão da cadeia de suprimentos, estratégia e gestão de operações, realizou-se uma pesquisa-ação na empresa pioneira na produção de nãotecidos no Brasil após a instalação de novas plataformas, que adicionaram capacidade produtiva e qualidade técnica ao produto acabado. Este cenário demandou um estudo para a modificação das suas estratégias de mercado e operacional em determinados segmentos de negócios. Utilizando-se de registros da própria empresa, seus indicadores de desempenho tipo BSC, relatórios setoriais e informações técnicas dos equipamentos, estudaram-se as inter-relações de atributos dos produtos acabados, como cor, diâmetro e largura, com a geração de resíduo do processo produtivo para o delineamento da readequação estratégica e operacional. Concluiu-se que, as plataformas produtivas de tecnologia atualizada tendem a direcionar seus produtos para segmentos de mercado que apresentam alta rentabilidade. Também se conclui que em determinadas situações advindas das características das plataformas produtivas de nãotecidos, há a necessidade de alteração de mix de produção para a adequação do sistema produtivo frente a uma nova realidade de mercado. / This work aims the study of strategic and operational re-adequation in the nonwovens market, belonging to the third generation of the petrochemical supply chain, in the reality of global consolidation by suppliers and customers. This sector is characterized as capital intensive and has continuous flow production system, with the intrinsic generation of waste as a byproduct from its production process. Based on references of supply chain management, strategy and operations management, this study was developed at a Brazilian pioneer nonwoven production company after its installation of state-of-art production equipments, which added production capacity and technical quality to the finished good. This scenario required a study to change its strategy and operational marketing in certain business segments. Using company´s records, keys performance indicators (BSC type), sector reports and technical information about the equipments, we studied the interrelationships of finished products attributes, such as color, diameter and width, with the generation of waste production process for the design of strategic and operational alignment. We concluded that the production equipments with modern technology naturally drive their products to high profitability market segments. In certain situations, because of these equipments and the company's positioning in the market, there is a production mix change in order to suit the new reality of the production system.
7

Developing an assessment tool for measuring total quality management in SASOL's Steam Station Plant / L.E. Amorighoye

Amorighoye, Lucky Eyituoyo January 2009 (has links)
Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
8

Developing an assessment tool for measuring total quality management in SASOL's Steam Station Plant / L.E. Amorighoye

Amorighoye, Lucky Eyituoyo January 2009 (has links)
Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
9

Predictive Control for Wireless Networked Systems in Process Industry

Henriksson, Erik January 2014 (has links)
Wireless networks in industrial process control enable new system architectures and designs. However, wireless control systems can be severely affected by the imperfections of the communication links. This thesis proposes new methods to handle such imperfections by adding additional components in the control loop, or by adapting sampling intervals and control actions. First, the predictive outage compensator is proposed. It is a filter which is implemented at the receiver side of networked control systems. There it generates predicted samples when data are lost, based on past data. The implementation complexity of the predictive outage compensator is analyzed. Simulation and experimental results show that it can considerably improve the closed-loop control performance under communication losses. The thesis continues with presenting an algorithm for controlling multiple processes on a shared communication network, using adaptive sampling intervals. The methodology is based on model predictive control, where the controller jointly decides the optimal control signal to be applied as well as the optimal time to wait before taking the next sample. The approach guarantees conflict-free network transmissions for all controlled processes. Simulation results show that the presented control law reduces the required amount of communication, while maintaining control performance. The third contribution of the thesis is an event-triggered model predictive controller for use over a wireless link. The controller uses open-loop optimal control, re-computed and communicated only when the system behavior deviates enough from a prediction. Simulations underline the methods ability to significantly reduce computation and communication effort, while guaranteeing a desired level of system performance. The thesis is concluded by an experimental validation of wireless control for a physical lab process. A hybrid model predictive controller is used, connected to the physical system through a wireless medium. The results reflect the advantages and challenges in wireless control. / <p>QC 20140217</p>
10

Um estudo sobre o processo de trabalho na indústria automática de vidro /

Souza, Henrique Pavan Beiro de. January 2011 (has links)
Orientador: Adilson Marques Gennari / Banca: Felipe Luiz Gomes e Silva / Banca: José Walter Canoas / Resumo: A organização do trabalho na indústria automática de vidro é diretamente influenciada pela tecnologia inserida no processo produtivo. Neste ramo, uma cadeia integrada de autômatas realiza as operações físico-químicas que dão corpo ao produto final. Assim, o trabalhador não se envolve diretamente na fabricação e/ou montagem, ficando apenas como supervisor do processo. Isto implica uma série de características importantes à indústria automática vidreira: não só o processo de trabalho em si é marcado por tal nuance tecnológica como também - e conjuntamente com aquele - os processos de gestão e organização da empresa como um todo. Ao tratar da relação entre tecnologia e processo produtivo, não podemos deixar de analisar a própria relação capital/trabalho em sua dinâmica histórica. Por isso, o presente estudo se volta para uma análise crítica, com viés marxista, das principais formas de gerência do trabalho surgidas ao longo da história do capitalismo. Primeiramente, destacamos as vicissitudes da divisão do trabalho na manufatura, considerando o processo de subsunção formal à subsunção real do trabalho ao capital, ou seja, estudamos como ocorre a inserção da maquinaria no processo produtivo. Em seguida, analisamos o taylorismo e o fordismo - bem como o conceito de racionalização - como mecanismos de controle do trabalho operário. Por fim, investigamos a indústria de processo contínuo - ramo no qual se insere a indústria automática de vidro -, contrapondo-a com as características das indústrias tayloristas e fordistas / Abstract: The organization of work in the auto glass industry is directly influenced by technology inserted in the production process. In this business, an integrated chain of automata performs the physical-chemical operations that embody the final product. Thus, the worker does not get directly involved in manufacturing and/or assembly, being only a supervisor of the process. This implies a number of important features to the auto glass industry: not only the work process itself is marked by such technological nuance but also - and along with that - the processes of management and organization of the company as a whole. In addressing the relationship between technology and production process, we must search capital / labor relation in its historical dynamic. Therefore, this study turns to a critical analysis, biased Marxist, of the main ways of management work that emerged throughout the historyof capitalism. First, we highlight the vicissitudes of division of labor in manufacturing, considering the process of formal subsumption to real subsumption of labor to capital, ie, we study how the inclusion of machinery occurs in the production process. We then analyze Taylorism and Fordism - as well as the concept of rationalization - as mechanisms of control of labor worker. Finally, we investigate the continuous process industry - in which sector the auto glass industry is inserted - contrasting it with the characteristics of Taylorist and Fordist industries / Mestre

Page generated in 0.0563 seconds