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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.
141

Opportunities for CO2 Reductions and CO2-Lean Energy Systems in Pulp and Paper Mills

Möllersten, Kenneth January 2002 (has links)
<p>The risk for climate change is a growing concern for theglobal society. According to what is known as the Kyoto Protocol,developed countries have committed themselves to reduce theirgreenhouse gas (GHG) emissions. The purpose of this thesis hasbeen to analyse opportunities for CO2 reductions in Swedish pulpand paper mills. The pulp and paper industry accounts forsignificant shares of the Swedish utilisationof both electricityand, in particular, biomass fuels. In this thesis, it has been agoal to focus not only on the technical potential of alternativesfor CO2 reductions in the energy systems of pulp and paper mills,but also on analysing the costeffectiveness of the studiedmeasures. Moreover, the analysis has covered questions concerningthe capacity and willingness among the actors involved with thepulp and paper mills’energy systems to realise CO2reduction potentials.</p><p>A broad techno-economical evaluation of available technologiesfor increased power production as well as more efficient energyutilisation is carried out. Furthermore, a more indepth analysisof pulp mill-based biomass energy with CO2 removal and permanentsequestration (BECS) is presented. An evaluation is made of thepotential for pulp and paper production with a negative CO2balance through the implementation of BECS. In recent yearsoutside suppliers, mainly energy service companies (ESCOs), havebegun to operate energy facilities in some Swedish pulp and papermills. Based on interviews with managers from pulp and papercompanies and ESCOs, the main driving forces behind theincreasing co-operation as well as the opportunities and riskswith energy related co-operation are presented.</p><p>Furthermore, the technical possibility of carbon-negativitythrough the implementation of BECS is discussed in relation tocarbon management on both corporate and global levels. The extentto which CO2-reducing measures in pulp and paper mills arerealised will have an impact on Sweden’s capacity to reachCO2 reduction targets. Whether or not technologies for CO2capture and sequestration are developed and implemented inSwedish pulp mills has a very large impact on the size ofSweden’s long-term CO2 reduction potential. Moreover, thedevelopment of business and competence focus in pulp and papercompanies and ESCOs suggests that cooperation will become ofincreasing importance for future sustainable industrial energymanagement.</p><p><b>Keywords:</b>CO2 reduction, pulp and paper industry, energysystem, biomass, CO2 capture and sequestration, black liquor,gasification, power production, outsourcing, sustainable energymanagement</p>
142

Molecular and phenotypic characterization of the microbial communities in two pulp and paper wastewater treatment systems

Frigon, Dominic. January 1998 (has links)
Phylogenetic hybridization and phenotypic fingerprinting were applied to the analysis of bacterial communities in wastewater treatment systems. These approaches were aimed at (i) developing monitoring tools able to foresee operational problems, and (ii) providing the rationale to optimize the operation of bioreactors. The work presented is intended to first describe the community found in two reactors treating pulp and paper mill effluent, and second evaluate the possibilities of these techniques with respect to the development of new monitoring tools. / Phylogenetic membrane hybridization showed that the bacterial communities were dominated by Alpha and Beta Proteobacteria, a structure probably linked to the low F:M ratio. Other important factors determining the community structure were the proportion of COD in the high molecular weight fraction, the sludge age, phosphate addition, and the concentration of specific compounds (alcohols, phenols, volatile fatty acids) in the influent. The community structure partly determined the sludge characteristics demonstrating its potential value in the assessment of reactor performance. The results obtained by phylogenetic membrane hybridization suggest that the probes used in a monitoring tool would not need to be targeted to the species level to provide relevant information. However, they also suggest that the technique is more sensitive to changes in population density as opposed to changes in bacterial metabolism. / Phenotypic fingerprinting measured a smaller difference between the communities of the two reactors studied than what was measured by phylogenetic membrane hybridization. However, differences in heterotrophic activities observed between the two communities were linked to differences in influent composition.
143

An evaluation of a performance management system in the SA pulp and paper manufacturing industry : a case study.

Camp, Pauline. January 2003 (has links)
This study evaluates the implementation of a performance management system within a division of a company operating in the pulp and paper manufacturing industry. The research has been carried out in order to establish the perceived effectiveness of a performance management system as well as to identify areas where the system can be improved upon. An empirical study was carried out in the form of an e-mailed questionnaire to approximately 350 employees at Paterson grading level Upper C to Upper 0 across all mills, covering all aspects of the performance management system which included the process of establishing individual performance agreements, performance feedback as well as performance rewards. An analysis on the relationship between salary, salary increase percentage and performance positioning was also carried out. The survey data showed an overall positive level of satisfaction with the performance management system. A shortcoming, however, was found in the link between performance and pay, which very few of the employees surveyed were satisfied with. / Thesis (MBA)-University of Natal, Durban, 2003.
144

Wood chip exports and the challenges faced by private pulpwood farmers in Southern KwaZulu-Natal.

Naidoo, Lenny. January 2011 (has links)
The South African forestry industry has contributed significantly to the economic growth of the country by the planting of trees and the processing of these trees for the export market. With the increased demand for wood chips, the wood chip industry is concerned that the plantation resource that is currently available may not be adequate to fulfil the production required for future wood chip export. The purpose of this study is to examine the trends in wood chips exports from the Port of Durban and to examine the stability and growth of private pulpwood production in Southern KwaZulu-Natal. The forestry pulp and paper sector and its related downstream manufacturing enterprises is an important part of the KwaZulu-Natal economy. Eucalyptus and wattle timber are used to manufacture pulp and are exported in the form of wood chips. The Durban Wood Chipping facility is aimed at the export of wood chips from Durban to pulp and paper manufacturers in Japan. The methodology used in this study included questionnaires and semi-structured interviews that were held with the respondents involved in the forestry industry. A questionnaire was sent electronically to 119 participants being the total population of timber farmers that supply NCT Durban Wood Chips. A total of 33 respondents completed the questionnaire resulting in a 27.73% response rate. Three key personnel, with a strong forestry background, belonging to NCT Forestry Cooperative limited were selected as participants for the qualitative aspect of the study. The findings of the study showed that wood chips exports have increased from the Durban facility between 2006 and 2011. This came from recent research literature as well as data from NCT Durban Wood Chips (PTY) LTD. Dominant challenges faced by the farmers were land reform, transportation costs and municipal rates. Land claims, road infrastructure, economics (cost vs income) and demand for timber were the most challenging factors affecting private timber production into the future. The qualitative and quantitative results confirm that timber production is definitely increasing and hence contributing to stability of private pulpwood production in Southern KwaZulu-Natal. / Thesis (MBA)-University of KwaZulu-Natal, Westville, 2011.
145

Responses of wild freshwater fish to anthropogenic stressors in the Waikato River of New Zealand

West, D. W. January 2007 (has links)
Thesis (Ph.D.)--University of Waikato, 2007. / Title from PDF cover (viewed March 19, 2008) Includes bibliographical references (p. 99-118)
146

Influência do valor da madeira de mercado sobre o ordenamento de florestas plantadas para o suprimento parcial de uma indústria de celulose e papel: uma aplicação da programação linear. / Influence of the market wood value on the management of planted forests partially supplying a pulp mill: an application of linear programming.

Fábio Luís Brun 11 April 2002 (has links)
De maneira geral, o abastecimento de madeira de indústrias de celulose brasileiras provém de áreas plantadas próprias e de madeira comprada no mercado. Programas de planejamento florestal de longo prazo procuram, normalmente, abranger o manejo da floresta plantada de forma dissociada à aquisição de madeira de fontes externas. O objetivo deste estudo é avaliar o impacto da variação de valores de aquisição da madeira de mercado em modelos de programação linear que consideram seu volume adquirido como uma das variáveis-resposta. Fundamentado em dados florestais de 155 Unidades de Produção fornecidos pela International Paper do Brasil Ltda., empresa do ramo de papel para imprimir e escrever situada em Mogi-Guaçu, Estado de São Paulo, o trabalho apresenta resultados provenientes da geração de 80 modelos de programação linear submetidos a cinco diferentes cenários de valores de madeira de mercado. As abordagens dos modelos foram divididas em: modelos de maximização do valor presente líquido e modelos de minimização do valor do custo presente, subdivididos em modelos Global e Regionalizado (procurando observar uma condicionante administrativa da empresa), ordenados ou de produção livre e, finalmente, submetidos ou não a restrições operacionais de área máxima de colheita. Os resultados permitem observar que as diferentes abordagens de planejamento possuem graus variados de sensibilidade a variações de valores de madeira de mercado, notadamente os modelos de minimização do valor presente do custo. Esta sensibilidade pode ser medida pelas variações provocadas nos programas de colheita de madeira própria e compra de madeira de mercado, pela flutuação das idades médias de colheita, pelos resultados das funções-objetivo e pelo percentual de aproveitamento de área própria. Os dados também sugerem que há vantagem em manejar a floresta pelo modelo Global, que desconsidera os limites administrativos da empresa. Também, pode-se afirmar que a maximização do valor presente líquido das prescrições é a abordagem preferível em função de demonstrar maior robustez na geração de planos de manejo menos sensíveis aos diferentes cenários de valor da madeira de mercado. / Generally, the Brazilian pulp industry wood supply is largely provided by planted forests owned by the companies and wood purchased in the market. Long term planning programs usually address the two supplying sources – fee forests and market wood -separately. The main objective of this study is to assess the impact of different wood acquisition value scenarios in linear programming models that consider the amount of purchased wood as one of the variables. Based on data of 155 Production Units supplied by International Paper do Brasil Ltda., a printing paper company located in Mogi-Guaçu, State of São Paulo, the study presents results from the generation of 80 linear programming models submitted to five different wood acquisition value scenarios. The approach was divided into: maximization of net present value and minimization of the present cost, divided into Global and Regionalized models (pertaining to a company administrative restriction), with regulated or floating production and submitted or not to operational restrictions as a maximum harvesting area. Results allow observing that the different modeling approaches show different degrees of sensitivity to variations in the wood acquisition value – notably the minimization models. That sensitivity can be measured against variations in the harvesting and wood purchase programs, the floatation of the average harvesting ages, results of the objective function values and the percentage of utilization of fee lands. Results also suggest that there are advantages in managing the forest through the Global model, not considering the actual administrative limitations. Also, the maximization approach is the preferred one once it demonstrates more robustness through the generation of management programs less sensitive to the different proposed wood acquisition value scenarios.
147

Gestão de malhas de controle no processo de fabricação de papel = estudo de caso = Control loop management in papermaking process: case study / Control loop management in papermaking process : case study

Frias, Alessandro Rodrigues, 1977- 23 August 2018 (has links)
Orientador: Flávio Vasconcelos da Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-23T03:09:02Z (GMT). No. of bitstreams: 1 Frias_AlessandroRodrigues_M.pdf: 5596398 bytes, checksum: df7498d6968158f9178e007fdd72c6ff (MD5) Previous issue date: 2013 / Resumo: A Gestão de Malhas de Controle ou CLM (Control Loop Management) tem-se mostrado uma ferramenta importante para monitorar o funcionamento das malhas de controle nas indústrias, permitindo aumentar a produtividade e a qualidade por meio da redução no consumo de insumos e estabilidade da planta. Com isso, têm-se as justificativas necessárias para se pesquisar e aprimorar as técnicas existentes para gestão de malhas de controle nas indústrias. Este trabalho apresenta um estudo de caso sobre Gestão de Malhas de Controle em ambiente industrial por meio de um procedimento prático utilizando a metodologia DMAIC (Definir, Medir, Analisar, Implementar e Controlar) e também os principais índices de desempenho utilizados no software Sindus OPP como: Variabilidade, Erro Médio, Integral do Erro Absoluto (IAE), Índice de Capabilidade do Processo (CPK), Cruzamento de Setpoint (SP), Percurso da Válvula, Reversão e Saturação da Válvula na gestão on-line de malhas de controle. A revisão bibliográfica abrange os principais conceitos de gestão de malhas de controle, fundamentação teórica sobre a metodologia proposta para gestão de malhas, indicadores de desempenho e também sobre o processo de fabricação de papel, pois o estudo de caso apresentado neste trabalho foi realizado em malhas de controle do sistema de preparação de massa para fabricação de papel. Dentre os resultados obtidos destaca-se a redução de variabilidade das malhas de controle de nível do tanque de água fresca (96,9% menor), do tanque de massa refinada (98,6% menor) e do tanque de mistura (98,3% menor). A redução dos KPIs Técnicos das malhas de controle mostra que as ferramentas de gestão on-line de malhas de controle utilizadas no software Sindus OPP são práticas e eficazes, pois, permitiram fazer a gestão das malhas com foco em redução de variabilidade e melhoria contínua do processo de fabricação de papel / Abstract: The Control Loop Management (CLM) has been an important tool to monitoring the operation of the control loops in industry, allowing to increase productivity and quality through reducing the consumption of raw materials and plant stability. With this, there are the necessary justifications to research and improve the existing techniques for managing control loops in industry. This paper presents a case study on Control Loop Management in industrial environment by a practical procedure using the DMAIC methodology (Define, Measure, Analyze, Improve and Control) and the key performance indicators used in software Sindus OPP: Variability, Average Error, Integral of Absolute Error (IAE), Process Capability Index (CPK), Setpoint (SP) Crossing, Valve Travel, Valve Reversals and Valve Out Limit in online control loop management. The literature review includes the major concepts of Control Loop Management, the theoretical foundation of the proposed methodology for managing loops, performance indicators and also about the papermaking process, because the case study presented in this paper was performed on control loops of the stock preparation system for papermaking. Among the results highlight the variability reduction of control loops of the level of fresh water tank (96.9% less), of the refined pulp tank (98.6% less) and mixing tank (98.3% less). The reduction of Technical KPIs of control loops shows that the online management tools of control loops used in software Sindus OPP is practical and effective, because it allowed to manage the loops with focus on reducing variability and continuous improvement of papermaking process / Mestrado / Sistemas de Processos Quimicos e Informatica / Mestre em Engenharia Química
148

Secagem convectiva de papel reciclado com incorporação de corantes naturais / Convective drying of recycled paper with incorporation of natural dyes

López González, Néstor David 21 August 2018 (has links)
Orientadores: Melissa Gurgel Adeodato Vieira, Sandra Cristina dos Santos Rocha / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-21T04:23:24Z (GMT). No. of bitstreams: 1 LopezGonzalez_NestorDavid_M.pdf: 6381922 bytes, checksum: e497b1236a95bb6095b1c33957146b02 (MD5) Previous issue date: 2012 / Resumo: O papel está presente em muitas das atividades do cotidiano que vão desde usos sanitários, passando pelas embalagens até fins educativos. Este material que teve sua origem há quase 2000 anos, continua sua evolução na procura de alternativas limpas para seu reaproveitamento. Novos processos de reciclagem, secagem e a incorporação de materiais alternativos para melhorar as propriedades do papel fazem desta área de pesquisa a base para a criação de novas tecnologias e produtos com apelo ambiental. Neste contexto, este trabalho teve como objetivo a avaliação da reutilização de papel de escritório na forma de papel cartão com adição de extratos corantes naturais Carmim de cochonilha, Cúrcuma e Urucum, implementando um processo de destintagem dos papéis a serem reciclados e secando o papel em um secador convectivo em escala laboratorial para obter papel cartão artesanal colorido. Para isto, foi determinada uma formulação para cada uma das três polpas a serem tingidas com os corantes naturais e construídas as curvas de secagem para diferentes condições de secagem. Efetuou-se uma análise comparativa da qualidade dos papéis obtidos em diferentes condições de secagem e avaliou-se a degradação da cor dos papéis obtidos sob diferentes condições de iluminação. O estudo da secagem mostrou que as polpas fabricadas com cada um dos três corantes apresentaram processos de secagem equivalentes apesar de ter formulações diferentes. Além disso, uma análise estatística mostrou que a velocidade e a temperatura do ar de secagem influenciam positivamente o processo, afetando a duração deste. Na avaliação da qualidade dos papéis verificou-se que esta pode ser afetada por variações nas condições de secagem. Uma menor qualidade foi obtida em papéis secos sob condições mais drásticas de velocidade e temperatura do ar. Os testes de colorimetria realizados nas amostras evidenciaram que as condições de secagem podem modificar a saturação das cores dos papéis, gerando diferenças colorimétricas nos papéis obtidos e apresentando cinéticas de degradação diferentes para cada papel fabricado. Os extratos corantes de Carmim de cochonilha, Urucum e Cúrcuma apresentaram boa estabilidade no teste de abrigo à luz, mas nos testes realizados com luz ultravioleta e fluorescente a estabilidade das cores foi baixa. O carmim de cochonilha se apresentou como o corante com maior estabilidade e poder tintorial. Os corantes naturais analisados nesta pesquisa mostraram potencial para serem utilizados na fabricação de papéis reciclados artesanais / Abstract: The paper is present in many everyday activities from sanitary uses, through the packaging until educational purposes. This material was originated almost 2000 years ago, and continues its evolution in the search of environmental alternatives to be reused. New processes to recycling, drying and the incorporation of alternative materials carry out an important role for the creation of new products and new technologies with environmental appeal. In this context, this work aimed the evaluation of office paper in the form of cardboard with the addition of natural extracts dyes such as Cochineal Carmine, Turmeric and Annatto, using a de-inking process of paper and drying in a convective-scale laboratory dryer for obtain a colorful handmade paper card. For this, a formulation was determined for each of the three paper pulp to be dyed with natural dyes, the drying curves were analyzed for different drying conditions, moreover a comparative analysis of the quality of the paper obtained under different conditions of drying was accomplished and the degradation of color paper obtained under different lighting conditions was evaluated. The study showed that drying of the paper pulp manufactured for each of the three dyes present equivalent drying processes, despite that these had different formulations; in addition, a statistical analysis showed that the air velocity and temperature of the drying air have a positively influence in the process. In the study of quality of paper, it has been demonstrated that variations in the drying conditions affects the quality of paper, such as reducing these with the increase in velocity and air temperature. The colorimetric test showed that the drying conditions can change the color saturation of the paper, causing colorimetric differences in the papers obtained and having different degradation kinetics for each paper produced. The extracts of cochineal carmine, Annatto and Turmeric dyes showed good stability under the test of light; however, the stability for the test performed with ultraviolet and fluorescent light. The results using cochineal carmine dye presented greater stability and tinctorial power. Natural dyes tested in this study showed potential to be used in the manufacture of handmade recycled paper / Mestrado / Processos em Tecnologia Química / Mestre em Engenharia Química
149

Modificação quimica do amido de mandioca e estudo de sua aplicação em revestimento couche

Taparelli, Jesus Roberto 02 January 2005 (has links)
Orientador: Lucia Helena Innocentini Mei / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-04T05:33:53Z (GMT). No. of bitstreams: 1 Taparelli_JesusRoberto_M.pdf: 3122835 bytes, checksum: 2a962c8596eae20801290e744716b2cf (MD5) Previous issue date: 2005 / Resumo: Neste presente trabalho, foi estudada a grafitização de N-metilol acrilamida em amido de mandioca nativo, em meio aquoso, com proporções de 20, 30 e 40% em relação ao peso de amido, tendo como objetivo avaliar a aplicação técnica do produto resultante em formulações de tintas de revestimentos couché, aplicado sobre uma superficie de papel cartão. Estes novos polímeros, bem como o amido de mandioca e o amido de milho nativo, foram caracterizados por: (i) Análise Dinâmico-Mecânica (DMA), onde se conseguiu verificar moderadas modificações nas transições térmicas; (ii) Espectroscopia na região do Infravermelho(FT_IR); (iii) Microscopia Ótica (MO) e (iv) Microscopia Eletrônica de Varredura (MEV), onde percebeu-se mudanças morfológicas nos grânulos de amido modificado, que se apresentaram maiores que os do amido nativo. Para uma análise do comportamento destes polímeros em formulações de tintas de revestimentos couché, foi utilizado como referência padrão o látex de estireno-butadieno carboxilado, atualmente utilizado na indústria de papel, como ligante (ou resina) principal. Nas tintas de revestimentos couché desta tese, foram analisadas as aplicações feitas em papel cartão revestido, onde se utilizou para teste de imprimibilidade as seguintes análises: Pick teste seco; Pick teste úmido; alvura; teste de absorção superficial - K & N; brilho de impressão; rugosidade e absorção de óleo. Um bom revestimento deverá apresentar uma boa adesão à superficie do papel, evitando seu arrancamento do mesmo. Dos testes de arrancamento, todas as amostras dos revestimentos feitos com amido de mandioca, modificados com Nmetilol acrilamida, apresentaram excelentes resultados / Abstract: In this work, it was studied the graftization of native tapioca starch with of Nmethylol acrylamide (NMA) in aqueous media, at several proportions (20, 30 e 40%) relative to the starch weight, with the aim to evaluate the technical application of the product obtained in inks formulations used for finishing covering, applied over paper-card surfaces. The NMA and the native starch, as well as the starch derivatives, were characterized by: (i) Dynamic Mechanical Analysis (DMA), which showed mild modifications in the thermal transitions; (ii) lnfrared Spectroscopy (F_TIR); (iii) Oplical Microscopy (OM) and (iv) Electron Scanning Microscopy (SEM) which revealed morphological changes in the starch grains, being the modified starch grains bigger than those native. To analyze the behavior of these polymers in formulations of inks, used for finishing covering (known as couché paper card), it was utilized latex of styrene-butadiene - carboxylate as reference, current1yused as binder in the paper industry. For the paper card with the finishing covering it was utilized tests of printability as: dry pick test; wet pick test; whiteness; K and N test; shine of impression; roughness and oil absorption. In the printing process, the graphic ink used presents tacking that is responsible for a perpendicular force to the surface of the paper, which is able to peel its covering. The peeling tests done with the formulations modified with modified tapioca starch with Nmethylol acrylamide (NMA) presented very promising results / Mestrado / Ciencia e Tecnologia de Materiais / Mestre em Engenharia Química
150

The water component of the industrial location problem : British Columbia's pulp and paper industry

Mitchell, William Bruce January 1967 (has links)
A study in economic geography, this thesis attempts to determine the importance of water for process supply and effluent disposal in industrial location decisions. It is postulated that industry faces physical, institutional, and technologic-economic constraints when evaluating the water component in location problems. Each of these three constraints is analyzed and evaluated for British Columbia's pulp and paper industry, with a view to discovering its effect on the range of spatial choice enjoyed by firms. A number of general conclusions emerge from the investigation. Although a theoretic location proof is not offered, the study raises a number of arguments which indicate water has been over-emphasized in industrial location decisions, and that industry exhibits greater spatial mobility regarding water requirements than is contended in the geographical and technical literature. Of the three constraints, it appears that those of a technologic-economic nature impose the severest limitations on spatial choice; physical, the least. Institutional regulations are found to provide industry with incorrect signals for decision making — the suggestion is offered that effluent control programs based upon economic rather than biological criteria would remove this problem. The implications of the above conclusions for future geographic inquiry regarding water management and development is considered in the concluding section of the study. / Arts, Faculty of / Geography, Department of / Graduate

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