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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.
131

Utvärdering av lufthalts- och nedfallsmätningar gjorda vid Korsnäsverken : Samband mellan miljöförbättrande arbete i pappers- och massaindustrin och föroreningar i närområdet / Evaluation of air concentration- and deposition measurements at Korsnäs : Relationship between environmental work in the pulp and paper industry and pollution in the surrounding area

Alsmyr, Michaela January 2013 (has links)
En nedgång har setts i Sverige och Europa när det gäller luftföroreningar de senast årtiondena. Nedgången beror bland annat på minskade emissioner från industrier, övergång från uppvärmning med olje- och kolpannor till fjärrvärme och förbättrad bränslekvalitet. Denna studie utvärderar lufthalts- och nedfallsmätningar gjorda i närheten av pappers- och massaindustrin Korsnäs i Gävle. Mätserierna startar vid sent 1970-tal och går fram till årsskiftet 2009/2010. Nedfall av stoft, sulfat, natrium, kalcium och lufthalter av svaveldioxid samt sot studerades. Jämförelser gjordes med Korsnäs miljöförbättrande åtgärder och emissioner under tidsperioden och med andra mätningar gjorda i Sverige och Gävleborgs län. Studien visade en nedgång av svaveldioxidhalterna i luften. Detta stämmer bra med en kraftig reduktion av svavelemissionerna från fabriksområdet under tidigt 1990-tal då installationer av reningsanläggningar skedde på de största emissionskällorna av svaveldioxid. En minskning av svavelhalten i eldningsoljan från Karskär Energi AB, ett energikombinat ägt av Korsnäs på samma fabriksområde, bidrog under samma tidperiod även till emissionsminskningen. Sothalten visade ingen nedåtgående trend under perioden men var säsongsberoende med i genomsnitt högre halter på vinterhalvåret. Troligtvis berodde detta på förbränningsanläggningar i närområdet, så som enskild förbränning och Karskär Energi AB. Fördelning av de högsta lufthalterna visade inte högre halter av svaveldioxid och sot när medelvindriktningen var ostlig och därmed blåste från fabriksområdet mot mätstationen utan när vindriktningen var sydvästlig och blåste från inlandet. Det totala stoft- och kalciumnedfallet visade ingen nedgång men hade i genomsnitt högre uppmätta halter på sommarhalvåret. Sulfatnedfallet visade högre halter under sent 1980-tal för att därefter minska och natriumnedfallet minskade något under perioden. Inga tydliga kopplingar kunde ses mellan lufthalter respektive nedfall och emissionerna från fabriksområdet när dataserierna sorterades efter vindriktning, vindhastighet och efter sommar- respektive vinterhalvår. Nedfall och lufthalter var inte högre, förutom för svaveldioxid, när jämförelser gjordes med andra mätningar i Sverige och Gävleborgs län och samtliga mätningar låg under periodens gällande nationella gränsvärden. / A decline has been seen in Sweden and Europe when it comes to air pollution the last decades. The decline is partly due to reduced emissions from industries, switching from heating using oil and coal boilers to district heating and better fuel quality. This study evaluates deposition and air concentration measurements made in the vicinity of the pulp and paper industry Korsnäs in Gävle. The measurement series starts at the late 1970s and goes up to year-end 2009/2010. Deposition of dust, sulphate, sodium, calcium and air concentrations of sulphur dioxide and soot were studied. Comparisons were made with Korsnäs environmental measures and emissions during the same time period and with other measurements made in Sweden and Gävleborgs County. The study showed a decrease in sulphur dioxide concentrations in the air. This fits well with a major reduction of sulphur emissions from the factory area in the early 1990s when installations of treatment plants were made at the largest emission sources of sulphur dioxide. Reducing the sulphur content of fuel oil from Karskär Energi AB, an energy combine owned by Korsnäs in the same factory area, contributed to the decrease during the same time period. Air concentrations of soot showed no downward trend over the years, but were seasonal, with higher average soot concentrations in the winter. This was most likely caused by the burning of fuel oil from both the private sector and Karskär Energi AB. The largest air concentrations did not show higher levels of sulphur dioxide and soot when the mean wind direction was easterly and thus blew from factory area toward the monitoring station but when the wind direction was southwesterly and blew from inland. The total dust and calcium deposition showed no decline but had higher average measured levels in the summer. Sulphate deposition showed high levels during the late 1980s but has thereafter decreased. The sodium deposition decreased a little during the time period. No clear connection was found between deposition/air concentrations and emissions from the factory area when the data series were sorted by wind direction, wind speed and after the summer and winter months. Depositions and air concentrations were not higher except for sulphur dioxide when the comparison was made with other measurements in Sweden and Gävleborg County. All measurements were below the then current national limits.
132

Study of coliform bacteria in Canadian pulp and paper mill water systems : their ecology and utility as health hazard indicators

Gauthier, Francis. January 2000 (has links)
Coliform bacteria have long been used to indicate fecal contamination of food, water, and solid surfaces, and thus the presence of a health hazard. In this study, the in-mill water and external effluent treatment systems of seven typical Canadian pulp and paper mills were shown to support the growth of numerous coliforms, especially Klebsiella spp, Escherichia coli, Enterobacter spp., and Citrobacter spp . Mill coliforms were shown to be not just simple transients from feedwater or furnish (wood), but to be continuously growing, especially in the primary clarifiers. Therefore, coliforms and fecal coliforms cannot be used as fecal contamination indicators in pulp and paper mill water and effluent treatment systems. / N2-fixing coliform populations were detected in mill water systems and were analyzed using N2-fixation assays and nitrogenase gene (nifH) probing. Both active in situ populations and cultured microbial isolates were tested. Active N2-fixation was demonstrated in six primary clarifiers. Measurement of the numbers and composition of the total culturable bacterial community in a primary clarifier revealed that approximately 50% of all aerobic cells contained nifH , of which >90% were Klebsiella. Coliforms growing on MacConkey agar plates from the primary clarifier were all identified as Klebsiella and 100% of these Klebsiella contained the nifH gene. Preliminary estimates indicate that the amount of N2 fixed per day is substantial in some clarifiers.
133

Mitigating Climate Change - The Need For A Carbon Strategy : A Case Study On Carbon Responses In The Swedish Pulp and Paper Industry

Karlsson, Fredrik, Sissay Girma, Tewodros January 2012 (has links)
Climate change has become an increasingly important strategic issue for businesses to deal with. The stake is high particularly for those in energy-intensive industries as governments are implementing legislations that limit the carbon emission coming from these industries. Not only are such companies’ carbon emission confronted by regulatory bodies, but also various stakeholders such as customers and investors. Such pressures increased the business relevance of the issue and have provided various strategic contexts and drives. Businesses have responded in different ways to the changes that are coming with climate change. The purpose of this study was to provide insight into the dynamics and characteristics of carbon strategies. The case study companies were three pulp and paper companies located in Sweden, all subjected to the EU ETS regulation. In order to fulfill the purpose we have developed an analytical framework which we applied to the empirical findings. Based on our analysis we concluded that there are several factors that determine and drive the development of carbon strategies: sustainability, energy efficiency, market competition, and owners. The findings also revealed that the most prevalent response type was an optimization strategy, which is enhancing the carbon productivity from operational activities. The findings also confirmed the usefulness and comprehensiveness of the analytical framework employed to the understanding of carbon strategies and development factors.
134

Evaluation of the bleach-enhancing effects of xylanases on bagasse-soda pupil

Bissoon, Sadhvir January 2002 (has links)
Submitted in fulfillment of the requirements for the Degree of Doctor of Technology: Biological Sciences, M.L. Sultan Technikon, 2002. / The extent of diffusion and surface modification of a purified 23.6 kDa xylanase isolated from Thermomyces lanuginosus on bagasse pulp was evaluated. Polyclonal anti-xylanase antibodies were raised in two rabbits and in conjunction with immunogold labeling and microscopic studies enzyme diffusion and degradation studies were performed. The purity of the xylanase was confirmed by SDS-PAGE and western blots confirmed the antigen-antibody hybrid on the nitrocellulose membrane. / D
135

Development of a layout for effective use of space in a block stacking warehouse

Gunnervald, Sebastian, Gustafsson, Viktor January 2017 (has links)
Historically, the paper market has consisted of few customers with high demands. However, the market has changed and nowadays it consists of many customer with lower demands, which causes problems in the warehouse process of Braviken Papermill. The main problem is that the utilization rates in the storage bays are low due to the relatively large bays compared to the order quantities. The purpose of this project is to develop a new set of bays that fits the current market and increases the utilization rates. The goal of the new set is to decrease the amount of manual operations and instead use the full potential of the allocation system.    The new set of bays consist of four bay types, dimensioned for 2, 4, 8 and 16 reel stacks respectively. Several experiments are done, and the new set of bays performs better than the current one, in terms of the utilization rates for storage events in the bays. The average utilization rate is significantly higher for the new set compared to the current. A decrease in effective storage space can be compensated by an increased degree of utilization. Also, it is beneficial with more and smaller bays in a market situation like the one of Holmen Paper.
136

Exploring the value drivers of industrial consultancy services in the age of digitalization : A study conducted in association with Sweco Industry

Bergh, Victor January 2020 (has links)
A number of studies have explored the drivers behind value creation, often referred to as value drivers. These studies point out that the generalizability of research on value creation to other contexts is difficult. One such context in which the value drivers remain unidentified is the context of industrial consultancy services. In the age of digitalization, where industries are becoming more complex and knowledge intensive, consultancy services have grown increasingly important for industrial customers. At the same time, globalization intensifies the competition on consultancy markets creating a high pressure on consultancy firms’ ability to continuously enhance value creation for their customers. Based on these challenges, the purpose of this thesis is to explore how value creation can be enhanced through the identification and utilization of value drivers in industrial consultancy services. Two research questions were formulated based on this purpose and addressed by means of a qualitative study conducted in the paper and pulp industry in Sweden. Semi-structured interviews were conducted with six managers and decision makers from five multinational companies that use consultancy services. The thematic analysis of the interviews led to the identification of 13 value drivers that play key roles in value creation in industrial consultancy services: Individual competence, Organizational resources, Availability, Personal relationship, Communication, Personal attributes, Timeliness, Usage of time, Performance, Cost, Customer-organizational involvement, Documentation and Progress by feedback. Ten among these drivers were considered benefits, while three were considered sacrifices. Consultancy firms should strive towards minimizing the negative effects on value creation caused by sacrificial value drivers and maximize the positive effects on value creation caused by beneficial value drivers. In addition, the thesis contributes a model in which the 13 value drivers can be used by both industrial customers of consultancy services and consultancy firms for the purpose of evaluating and enhancing value creation. Specifically, the model offers a tool that (I) compares different consultancy firms or projects in terms of value creation, (II) evaluates and analyzes projects and collaborations with respect to value creation and (III) enhances value propositions and value creating processes.
137

Study of coliform bacteria in Canadian pulp and paper mill water systems : their ecology and utility as health hazard indicators

Gauthier, Francis. January 2000 (has links)
No description available.
138

Participatory monitoring and evaluation of marine water quality, a case study of Sappi Saiccor, Umkomaas.

McPherson, Mamosa Eileen. January 2002 (has links)
Previously, issues concerning the use and conservation of the natural resources were restricted to certain groups of individuals, normally those considered to be scientific experts. However with the emergence of sustainable development and the adoption of its principles therein, there has been increased community concern over environmental quality issues resulting in pressure for transparency in environmental decision-making processes. The result has been a dramatic expansion in the number of organisations at the local, national and global scales committed to environmental improvement. This in turn has let to dramatic changes in the role of the public in decisions relating to natural resource management. Participatory development is now acknowledged as critical in achieving sound environmental management. The initiation of community-based environmental decision-making has led to the formation of new and interesting partnerships. Environmentalists, communities, policy makers and business people have begun to work together in an attempt to find consensus concernIng environmental problems and related socio-economic inequalities. This has resulted in the development of new ways of integrating local and scientific knowledge systems. This thesis illustrates community-based environmental decision-making in the management of the use of the south coast of Durban. It outlines a partnership, through the formation of the Permit Advisory Panel (PAP), comprising industry (Sappi Saiccor), government, through its Department of Water Affairs and Forestry, environmental organisations, and the local people in the monitoring of the impacts of effluent produced by the industry and disposed of into the sea. The aim of this thesis is to develop an alternative methodology that will be acceptable to all stakeholders, for the collection and analysis of data in the monitoring of the Sappi Saiccor effluent. This was achieved through the following objectives: to develop a methodology for the collection and analysis of data, to assess the performance of the new pipeline in terms of reduced aesthetic impacts of the effluent, to assess the role of local knowledge in the monitoring process, and finally to assess the role of this study in the functioning of the PAP. This thesis attempts to integrate qualitative and quantitative methodologies. The subjective local data collected by the divers is analysed using statistical methods to assess the impacts of the effluent on marine water quality and the effect the new pipeline has had in reducing these impacts. Qualitative surveys such as questionnaires and interviews were administered to assess the role of local knowledge in the monitoring process and also to assess the role this study has had in the functioning of the PAP. The statistical analysis did not reveal any major improvement in underwater visibility since the pipeline was extended. There is a 6% and 4% improvement in the number of effluent days and visibility respectively. This however is due to some limitations inherent in the data collection process, and as a result the improvement brought about by the pipeline extension has been toned down. An effluent and visibility index is therefore recommended as an alternative method of data collection and analysis to reduce the level of inaccuracy. The role of local knowledge is perceived by many of the PAP members as vital in the monitoring process. This study was therefore thought of as an important step in validating this local knowledge such that it can be a reliable data source to be used in the monitoring process. It also played an important role in resolving the conflict between the PAP members. It is therefore recommended that the divers data should be continually used in the monitoring process, though the divers have to be more actively involved. The PAP is therefore tasked with liasing with the community members, especially the divers such that they can assume a more active and responsible role within the PAP. They should be involved in the development of the methods of data collection and analysis. / Thesis (M.A.)-University of Natal, Durban, 2002.
139

Estudo da queima do lodo secundário da indústria de celulose em caldeira de leito fluidizado / Study of cellulose industry secondary sludge burning in fluidized bed boiler

Guaitolini, Maxwel 28 July 2014 (has links)
Made available in DSpace on 2015-03-26T14:01:17Z (GMT). No. of bitstreams: 1 texto completo.pdf: 719250 bytes, checksum: 88cbe0bf2708fae3d37f97ecb94a5554 (MD5) Previous issue date: 2014-07-28 / The lack of physical space to lay out waste generated by the process is one of the major is a residue derived from pulping, bleaching of cellulosic fibers, and papermaking process; originally having the composting practice as final disposition method. High financial resources are involved to this disposition practice, including sludge transporting costs to a suitable place. Thus, the objective of this work is to provide technical support for burning a waste generated by the pulp and papermaking process at Fibria-MS, the secondary sludge from effluent treatment station, in a high pressure steam generation fluidized bed boiler. In this study, the burst test of a biomass mixture and biological sludge in a fluidized bed boiler presented the following trends, when compared to a control period (burning biomass only): reduction of dry sample content; reduction of the calorific value as such; maintenance of the value of calorific value for the dry sample; increased boiler air flow; reduction of the recirculated air flow in the boiler; bed temperature maintenance, however with greater data variability; increase in particulate matter and TRS emissions of the boiler, yet, showing acceptable values, according to Conama resolution. It was possible to conclude that the burning of treatment station biological sludge in fluidized bed boiler presents itself as an attractive practice to the pulp and paper industry, contributing to reduced occupancy of the landfill. / O setor de Celulose e Papel está em claro processo de expansão, crescimento este ocasionado pela criação de novas unidades fabris bem como pelo aumento de produção das unidades já existentes. No caso do aumento de produção em unidades já existentes, a falta de espaço físico para dispor os resíduos gerados pelo processo é um dos grandes problemas dessa indústria. Dentre os vários tipos de resíduos gerados, destaca-seo lodo biológico da estação de tratamento de efluentes, o qual é um resíduo derivado dos processos de polpação e branqueamento das fibras celulósicas e dos processos de refino e formação da folha de papel, tendo, originalmente, a prática de compostagem para sua disposição final. Para este tipo de disposição final, incluindo os custos de transporte do lodo até o local adequado, recursos financeiros elevados estão envolvidos. Desse modo, o objetivo deste trabalho é fornecer subsídios técnicos para queima de um resíduo gerado no processo de fabricação de papel e celulose da indústria Fibria-MS, o lodo secundário da estação de tratamento de efluentes, em uma caldeira de leito fluidizado de geração de vapor de alta pressão. No presente trabalho, o teste da queima de uma mistura de biomassa e lodo biológico em uma caldeira de leito fluidizado apresentou as seguintes tendências, quando comparado a um período controle (queima apenas de biomassa): redução do teor seco da amostra; redução do valor do poder calorífico tal qual; manutenção do valor de poder calorífico para a amostra seca; aumento da vazão de ar primário da caldeira; redução da vazão de ar recirculado na caldeira; manutenção da temperatura do leito, porém com maior variabilidade dos dados; aumento das emissões de material particulado e TRS da caldeira, entretanto, apresentando valores aceitáveis, segundo resolução do Conama. Foi possível concluir que a queima de lodo biológico da estação de tratamento em caldeira de leito fluidizado apresenta-se como uma prática atrativa à indústria de Celulose e Papel, contribuindo para a redução de ocupação do aterro sanitário.
140

Estudo de aperfeiçoamento do sistema de tratamento de condensado contaminado da produção de celulose / Study of improving a foul condensate treatment of pulp production

Simão, Geraldo 31 July 2014 (has links)
Made available in DSpace on 2015-03-26T14:01:18Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1024607 bytes, checksum: d790e435733c38f369dea4a0231609b0 (MD5) Previous issue date: 2014-07-31 / The industry of Kraft pulp production process generates large amount of foul condensate. Such condensates are potential pollutants impacting on investment, cost of operation and maintenance, power consumption, cost of chemical in the process, water consumption, effluent generation and odor. Systems useful for treatment of foul condensates from a Kraft pulp mill are formed by stripping systems which are columns of removing volatile contaminants condensed with the use of steam or air. This study aimed at improving the process of treating contaminated condensate in a plant of bleached eucalyptus Kraft pulp, existing, which presented poor treatment of condensate and due to this low efficiency did not use the total amount of treated condensate in the process, generating higher costs and increased effluent load. An assessment of the design data and operation of each of the three systems of stripping the existing plant. The variables and process controls, and offers technical alternatives for the treatment of contaminated condensate as well as use indicated of the entire treated condensate. / A indústria de produção de polpa celulósica Kraft gera no processo grandes volumes de condensados contaminados, oriundos do processo de cozimento e da evaporação de licor negro. Tais condensados são potenciais agentes poluidores impactando em investimentos, custo de operação e manutenção, consumo de energia, gasto de insumos químicos no processo, consumo de água, além de geração de efluente e odor. Sistemas usuais de tratamento de condensados contaminados de uma fábrica de polpa Kraft são formados por sistemas de extração de gases, que são colunas de remoção dos contaminantes voláteis dos condensados com uso de vapor ou ar. Este estudo teve como objetivo o aperfeiçoamento do processo de tratamento de condensado contaminado em uma planta de polpa Kraft de eucalipto branqueada, existente, que apresentava deficiência no tratamento dos condensados e, por conta desta baixa eficiência, não utilizava todo o condensado tratado no processo, gerando maiores custos e uma maior carga para o efluente. Foi realizada uma avaliação dos dados de projeto e de operação de cada um dos três sistemas de extração de gases da planta existente. Foram avaliadas as variáveis de processo e os controles e propostas alternativas técnicas para o tratamento do condensado contaminado bem como a utilização para todo o condensado tratado. Como resultado, foram identificadas as alterações que deverão ser executadas nos sistemas de tratamento de condensado e as alternativas para o uso de todo do condensado tratado, tendo como resultado a redução de custos e impactos ambientais.

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