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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

Towards a learning system for process and energy industry : Enabling optimal control, diagnostics and decision support

Rahman, Moksadur January 2019 (has links)
Driven by intense competition, increasing operational cost and strict environmental regulations, the modern process and energy industry needs to find the best possible way to adapt to maintain profitability. Optimization of control and operation of the industrial systems is essential to satisfy the contradicting objectives of improving product quality and process efficiency while reducing production cost and plant downtime. Use of optimization not only improves the control and monitoring of assets but also offers better coordination among different assets. Thus, it can lead to considerable savings in energy and resource consumption, and consequently offer a reduction in operational costs, by offering better control, diagnostics and decision support. This is one of the main driving forces behind developing new methods, tools and frameworks that can be integrated with the existing industrial automation platforms to benefit from optimal control and operation. The main focus of this dissertation is the use of different process models, soft sensors and optimization techniques to improve the control, diagnostics and decision support for the process and energy industry. A generic architecture for an optimal control, diagnostics and decision support system, referred to here as a learning system, is proposed. The research is centred around an investigation of different components of the proposed learning system. Two very different case studies within the energy-intensive pulp and paper industry and the promising micro-combined heat and power (CHP) industry are selected to demonstrate the learning system. One of the main challenges in this research arises from the marked differences between the case studies in terms of size, functions, quantity and structure of the existing automation systems. Typically, only a few pulp digesters are found in a Kraft pulping mill, but there may be hundreds of units in a micro-CHP fleet. The main argument behind the selection of these two case studies is that if the proposed learning system architecture can be adapted for these significantly different cases, it can be adapted for many other energy and process industrial cases. Within the scope of this thesis, mathematical modelling, model adaptation, model predictive control and diagnostics methods are studied for continuous pulp digesters, whereas mathematical modelling, model adaptation and diagnostics techniques are explored for the micro-CHP fleet. / FUDIPO – FUture DIrections for Process industry Optimization
132

Integration of Production Scheduling and Energy Management : Software Development

Ait-Ali, Abderrahman January 2015 (has links)
Demand-Side Management concepts have the potential to positively impact the financial as well as the environmental aspects of energy-intensive industries. More specifically, they allow reducing the energy cost for the industrial plants by dealing with energy-availability fluctuations. In this context, efficient frameworks for scheduling with energy awareness have been studied and showed potential to reduce the overall energy bill for energy-intensive industries, for instance stainless steel and paper plants. Those frameworks usually combine scheduling and energy optimization into one monolithic system. This work investigates the possibility of integrating the two systems by specific exchange of signals, while keeping the scheduling model separated from the energy-cost optimization model. Such integration means that the pre-existent schedulers and energy optimizers could be easily modified and reused without re-implementing the whole new system. Two industrial problems with different scheduling approaches are studied. The first problem is about pulp and paper production which uses the Resource Task Network (RTN) scheduling approach. The second one is about stainless steel production which is based on a bi-level heuristic implementation of an improved energy-aware scheduler. This work presents the decomposition methods that are available in literature and their application to the two industrial problems. Besides an improvement in the RTN approach for handling storages, this thesis describes a prototype implementation of the energy-aware RTN scheduler for paper and pulp production. Furthermore, this work investigates the performance of the application of different decomposition methods on different problem instances. The numerical case studies show that even though the decomposition decreases the solution quality compared to the monolithic system, it still gives good solutions within an acceptable duration with the advantage of having two separate pre-existent systems which are simply exchanging signals.
133

Site Study of Fibrous Sediments in Sandviken, Ångermanälven River Estuary, Sweden / Platsstudie av fibersediment i Sandviken, Ångermanälven, Sverige

Ghaderidosst, Joanna January 2020 (has links)
Pulp and paper industries in Sweden have since the end of the 19th century until late 70s been active in dumping wastewater into adjacent water bodies that have created fibrous sediments called fiberbank and fiber-rich sediment. Fiberbanks are large banks of predominantly organic material while fiber-rich sediment is fibrous sediment that has been mixed with bottom sediment. The fiberbanks comprise of high levels of processed wood fibres and contaminants such as heavy metals and persistent organic pollutants (POPs). It also produces carbon dioxide and methane gas by microbial activity and leaves the sediment with exit holes called pockmarks. These sediments have been proven to cause environmental harm to the benthic biological environment around it, also causing it to become anoxic/hypoxic. Some of the POPs bioaccumulate which also affect humans through fishing. If the fiberbanks are disturbed through e.g. mass movement, toxic contaminants could be released into the aquatic environment. Fiberbanks need to be remediated and more research is needed to characterise it. In-situ capping is a remediation technique that is being tested at the laboratory scale for its application to fiberbanks. It involves placing a layer of clean material on top of the sediment, in order to stabilize it and to limit contaminant release.Because of their high organic content and low density, these sediments might behave differently than typical natural sediments. Therefore, laboratory experiments are necessary to understand their key properties. This thesis focuses on the Sandviken site, for which the bearing capacity of fiberbanks, their thickness, and the compression rate of fiber-rich sediments are studied. The bearing capacity is the capacity for a sediment to hold a weight, and in the case of in-situ capping it is an important parameter to study. The thickness was interpreted from physical data collected by a fluid mud penetrometer (FluMu), from the University of Bremen to assess the fiberbank volume. Fiber-rich sediment is examined to expand the knowledge on its physical properties by testing consolidation and potential gas production.Bearing capacity was tested by placing sediment in a tank and placing a cap on top of it. The site thicknesses were interpolated in ArcMap into a visual topography where the volume could be calculated. Fiber-rich sediment consolidation was tested by placing the sediment in columns with different capping thicknesses. By monitoring bubbles and pockmarks, gas production was confirmed.Results show that the tank sediment construction kept its shape without collapsing or failing at the edges. Sediment/cap interface was sharp, it means little to no mixing between the layers. This proves that Sandviken fiberbank has enough bearing capacity to hold up a cap and that it contains contaminants well. FluMu interpretation resulted in a fiberbank volume of 51885 m3. The fiberbank thickest layer was interpreted as being in front of the sulphate factory which is a credible result. The fiberbank volume is not conclusive since the FluMu has not measured complete thicknesses of the layers. This can be said since thicknesses have been measured at a minimum of 6 m and the thickest point interpreted was 1,11 m. The fiber-rich sediment consolidation showed that a cap that is very thick will cause most consolidation and more rapid dissipation of pore water. Bubbles and pockmarks were observed and confirm gas production. / Papper- och massa-industrin i Sverige har varit aktiv fram till 1970-talet och har dumpat förorenat vatten i angränsande vattendrag. Detta har gett upphov till fibersediment som kallas fiberbank och fiberrikt sediment. Fiberbanker är stora banker av övervägande organiskt material och fiberrikt sediment är en blandning av fiberbank sediment och bottensediment. Fiberbankerna består mestadels av bearbetade träfibrer och föroreningar som tungmetaller och långlivade organiska föroreningar (POPs). Sedimentet producerar även växthusgaser genom mikrobiell aktivitet. Dessa sediment orsakat miljöskada på den biologiska bottenmiljön i omgivningen då den förlorat syreinnehåll. Samtliga POPs samlas i fisk vilket därav även påverkar människors hälsa. Om fiberbankerna skulle störas, släpps giftiga föroreningar ut i miljön. Fiberbanker måste åtgärdas och en saneringsteknik som undersöks i laboratorieskala är in-situ övertäckning. Detta innebär att placera ett lager av rent material ovanpå sedimentet för att stabilisera det och stoppa frigöring av föroreningar.På grund av sedimentets annorlunda karaktär är experiment i laboratorier nödvändiga för att förstå deras nyckelegenskaper. Detta arbete fokuserar på fiberbanken i Sandviken, fiberbankens bärförmåga, dess tjocklek och kompressionshastigheten för fiberrika sediment studeras. Bärförmågan är kapaciteten för ett sediment att hålla en vikt och när man ska belasta ett sediment med ett övertäckningslager är detta viktigt. Tjockleken av sedimentet undersöks för att bedöma fiberbankens volym i området. Fiberrikt sediment undersöks för att utöka kunskapen om dess fysiska egenskaper genom att testa konsolidering och om det producerar gas likt fiberbanksediment.Bärförmågan testades genom att placera sediment i en tank och placera ett lager av rent material på. Platstjocklekarna tolkades från fysiska data från en typ av sensor som penetrerar sediment och interpolerades därefter i ArcMap till en visuell topografi där volymen kunde beräknas. Fiberrik sedimentkonsolidering och gasproduktion testades genom att placera sedimentet i kolumner med olika locktjocklekar.Resultaten visar att bärförmågan av fiberbanksedimentet var tillräckligt för att klara av en grundlig belastning. Gränsen mellan sedimentet och övertäckningslagret var skarp i slutskedet, det innebär liten eller ingen blandning mellan skikten. Detta bevisar att sedimentet bibehåller övertäckningslager väl över sig då ytan är platt. Tolkningen av sensordata resulterade i en fiberbankvolym på 51885 m3. Fiberbankvolymen är inkomplett eftersom FluMu inte har uppmätt skiktens fullständiga tjocklekar eftersom tjocklekar har tidigare uppmätts till minst 6 m och den tolkade tjockaste punkten var 1,11 m. Den fiberrika sedimentkonsolideringen visade att ett övertäckningslager som är mycket tjock kommer att orsaka mest och snabbast konsolidering. Observationer bekräftade även gasproduktion i sedimentet.
134

Tillämpning av Process Failure Mode and Effects Analysis i pappers- och massaindustrin : En fallstudie på Svenska Cellulosa Aktiebolaget / Application of Process Failure Mode and Effects Analysis in the pulp and paper industry : A case study on Svenska Cellulosa Aktiebolaget

Gottberg, Gustav, Brelin, Markus January 2023 (has links)
Denna kvalitativa fallstudie syftade till att undersöka hur riskanalysmetoden Process Failure Mode and Effect Analysis (PFMEA) tillämpas och anpassas till pappers- och massaindustrin för att proaktivt hantera processrisker. Studien baserades på antagandet att Automotive Industry Action Group (AIAG) och Verband der Automobilindustries (VDA) PFMEA-metod från år 2019 även kan användas för en process där virke omvandlas till träflis. Data samlades in genom litteraturstudier, observationer, företagsdokument, intervjuer och workshops med processexperter. Processrisker analyserades med AIAG och VDAs PFMEA-metod och tematisk analys användes för att identifiera lämpliga anpassningar av metoden. Utifrån deltagande roller och tidsåtgången för PFMEA-aktiviteter analyserades även resurser för en PFMEA. Resultatet visade att AIAG och VDAs PFMEA-metod är tillämplig för en process där virke omvandlas till träflis, förutsatt att bedömningskriterierna för allvarlighetsgrad anpassas och fiskbendiagram, 5-varför och felträdsanalys inkluderas för en strukturerad analys av grundorsaker. Totalt identifierades 36 feltillstånd, varav grundorsaksanalyser prioriterades för fyra som hade effekter med en allvarlighetsgrad åtta eller högre. För prioriterade feltillstånd identifierades elva grundorsaker för vilka åtgärder kunde rekommenderas. För att genomföra analysen under en 16-veckorsperiod uppskattades kostnaden till cirka 212 571 kr i arbetstidskostnader. Studien visar att AIAG och VDAs PFMEA-metod är en strukturerad metod för att analysera processrisker även inom pappers- och massaindustrin, om anpassningar görs av bedömningskriterier och metoder för grundorsaksanalys inkluderas. Budgeteras kvalificerad personal kan en PFMEA genomföras inom 16 veckor på en process där virke omvandlas till träflis. / This qualitative case study aimed to investigate how the Process Failure Mode and Effect Analysis (PFMEA) methodology can be applied and adapted to the pulp and paper industry for proactive management of process risks. The study assumed that the Automotive Industry Action Group (AIAG) och Verband der Automobilindustrie (VDA) PFMEA method from year 2019 could also be utilized for a process that transforms timber into wood chips. Data were collected through literature reviews, observations, company documents, interviews, and workshops with process experts. Process risks were analyzed using the AIAG and VDA PFMEA method, and thematic analysis was applied to identify suitable adaptations of the method. Resources required for a PFMEA were also analyzed based on the roles of the participants and the time for conducting PFMEA activities. The results revealed that the AIAG and VDA PFMEA method is applicable to a process that transforms timber into wood chips, provided that the severity assessment criteria are adjusted and fishbone diagrams, 5-why analysis, and fault tree analysis are included for a structured examination of root causes. A total of 36 failure modes were identified, where root cause analysis was prioritized for four failure modes exhibiting effects with a severity rating of eight or higher. Eleven root causes were identified for the prioritized failure modes for which recommended actions could be proposed. The estimated cost of labor for conducting the analysis over a 16-week period was approximately 212 571 SEK. This study demonstrates that the AIAG and VDA PFMEA method is a structured approach for analyzing process risks, even within the pulp and paper industry, if adjustments are made to the severity assessment criteria and methods for root cause analysis are included. With the allocation of sufficient resources and qualified personnel, a PFMEA can be completed within a 16-week timeframe for a process involving the conversion of timber into wood chips.
135

Development of hydrophobic paper and wood products via metal ion modification

Rathnayaka Mudiyanselage, Oshani Nayanathara 08 August 2023 (has links) (PDF)
Renewable lignocellulosic materials are promising green plastic alternatives to fossil fuel-based plastics. However, the hydrophilic nature and poor water resistance of lignocellulosic materials have hindered their practical applications. This study reports a facile metal-ion-modification (MIM) route, swelling with aqueous metal ion solutions, and drying to convert conventional hydrophilic paper and wood pulp into biodegradable hydrophobic paper and tableware without the addition of hydrophobic sizing chemicals/materials. Metal ions such as Fe3+ and Zr4+ can coordinate with pulp fibers’ polar groups (i.e., O.H., C=O, and COOH) that induce self-assembly of their surface fibrillated “hairy” cellulose nanofibrils to form a more compact structure with fewer available O.H. groups for water sorption. The formation of coordination bonds with polar groups (i.e., O.H., C=O, and COOH) decreases the surface energy of pulp fibers and increases their hydrophobicity and water resistance. Only ~3 mg of metal ions is needed to induce the wettability transition in 1 g of kraft pulp, resulting in hydrophobic paper and tableware with water contact angles (WCAs) of 120-140° and displayed wet tensile strengths of up to 9.5 MPa, and low water absorbency, which were comparable to synthetic polymer films. This MIM technique can be integrated into the existing paper-making process for the scalable production of hydrophobic papers and tableware, providing an alternative route for developing sustainable and biodegradable plastic counterparts. The MIM-induced lignocellulose hydrophobization mechanisms were elucidated using X-ray photoelectron spectroscopy (XPS), Fourier transforms infrared spectroscopy (FT-IR), and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), and density functional theory (DFT). Furthermore, this MIM technique was also evaluated for its applicability in wood treatment. The treatment effectively tunes the wood surface from hydrophilic to hydrophobic, enhancing its water resistance. The MIM treatment significantly improved the dimensional stability of SYP, red oak, and poplar. For example, the Fe3+ treatment reduced the tangential swelling of SYP, poplar, and red oak by 57%, 50%, and 40%, respectively. Overall, this eco-friendly and facile MIM method holds promise for developing sustainable and biodegradable alternatives to conventional plastics, contributing to a more environmentally friendly future.
136

Omvärldsbevakning som en del av energimanagement : Hur elintensiva industrier kan utveckla strategier för proaktiv omvärldsbavakning av energipolitiska styrmedel / External Environment Monitoring Integrated in Energy Management : How electricity-intensive industries can develop strategies for external environment monitoring of energy political instruments

Isaksson, Paulina, Baekgaard Månsson, Amanda January 2022 (has links)
Energisektorn står idag för en tredjedel av de globala växthusgasutsläppen och på senare tid har tillgången på energi blivit en alltmer kritisk fråga då energisystemets utveckling har en avgörande roll för att nå nationella och internationella klimatmål. Energipolitiska styrmedel reglerar bland annat att företag och energisystemets utveckling går i rätt riktning och på grund av att många faktorer behöver inkluderas är energipolitiken ett komplext arbete. Tidigare studier visar att flertalet energipolitiska styrmedel har varit effektiva i syfte att minska klimatpåverkan från industriella verksamheter. Att som företag vara uppdaterad på förändringar inom energimarknaden och utvecklingen av energipolitiska styrmedel har kommit att bli viktigt då de påverkar verksamhetens energianvändning. Den svenska industrisektorn är en central användare av energi, där massa- och pappersindustrin står för omkring hälften av den totala energianvändningen inom Sveriges industrisektor. Energi är en integrerad fråga i massa- och pappersindustrin med utmaningar gällande miljöpåverkan, resursutnyttjande och hantering av förändrade energipriser. Ökad energieffektivitet för energiintensiva industrier är dessutom en viktig del i den globala klimatomställningen. Att integrera energimanagement i verksamheten är ett verktyg för att genomföra energieffektiviseringsåtgärder. Tidigare forskning och modeller för implementering av energimanagement i industriella verksamheter inkluderar däremot inte energirelaterad omvärldsbevakning, vilket skapar utrymme för vidare forskning. Denna studie syftar till att genom en omvärldsbevakning identifiera hur nuvarande och framtida energipolitiska styrmedel påverkar kemiska massa- och pappersbruk, med avseende på el som energibärare. Vidare undersöks hur förändringar på elmarknaden kan komma att påverka den kemiska massa- och pappersindustrin. Resultatet analyseras med utgångspunkt från ett befintligt ramverk för strategiskt arbete med energimanagement. Avslutningsvis appliceras ett företagsperspektiv genom en fallstudie på ett företag inom den kemiska massa- och pappersindustrin, för att undersöka interna strategier för energirelaterad omvärldsbevakning. Studien har genomförts med en kvalitativ metod samt med ett deduktivt angreppssett genom främst litteratur- och intervjustudier. Resultatet visar att flertalet styrmedel påverkar massa- och pappersindustrin idag och att majoriteten av dessa även väntas göra det i framtiden. Pågående förhandlingar inom Fit for 55, där ett antal direktiv väntas justeras och förhandlas om, kommer medföra effekter på industrin. Vad gäller elsystemets förändringar kan elpriset komma att bli mer varierande, både under dygnet men även under året, vilket grundas i en kombination av ökad elektrifiering och implementering av fler intermittenta energikällor i elsystemet. För att hantera dessa förändringar kan massa- och pappersindustrin se möjligheter i att bidra till en minskad energianvändning, exempelvis genom att delta på flexibilitetsmarknaden. Den befintliga teoribildningen kring energimangagement är inte fullständig då tidigare forskning saknar omvärldsperspektiv. Ett utökat ramverk för energimanagement har därför tagits fram där omvärldsbevakning integreras som ytterligare nyckelkategori. Vidare presenteras en modell som illustrerar ansvarsfördelnig för energirelaterad omvärldsbevakning sett ur ett perspektiv där företag, branschorganisationer och EU inkluderas. Avslutningsvis visar studien att elintensiva företag bör formulera tydliga interna strategier för hur energirelaterad omvärldsbevakning ska inkluderas i energimanagement. / Today, the energy sector accounts for a third of the global greenhouse gas emissions. The supply of energy has recently become an increasingly critical issue as the development of the energy system plays a crucial role to achieve national and international climate goals. Energy policy instruments regulate the development of companies' energy use and the energy system, but since several factors need to be included the field of energy policies is complex. Previous research shows that energy policy instruments have been effective to reduce the climate impact of industrial activities. Due to the constant development of the energy market and modifications of energy policy instruments, enterprises need to stay updated on these changes as they affect the business's energy use. The Swedish industrial sector is a central user of energy, where the pulp and paper industry accounts for about half of the total use of Sweden's industrial sector. Therefore, energy is an integrated issue in the pulp and paper industry with current challenges in terms of environmental impact, resource utilization, and changing energy prices. Increased energy efficiency in energy-intensive industries is important for confronting climate changes and energy management is a tool for implementing energy efficiency measures. However, current energy management literature and models for implementation in industrial firms do not include energy-related external environmental monitoring, which enables further research. The aim of this study is by conducting an external environmental analysis, identify how current and future energy policies affect the chemical pulp and paper industry, concerning electricity as an energy carrier. Furthermore, the study also seeks to investigate how changes within the electricity market affect the chemical pulp and paper industry. The results are analyzed based on an existing conceptual framework of energy management. Finally, an organizational perspective is applied to a company in the chemical pulp and paper industry to examine internal strategies for energy-related external environmental monitoring. The study is based on a qualitative research method with a focus on a deductive approach. The results show that serveral policy instruments affect the pulp and paper industry today, and the majority of these are also expected to do so in the future. Ongoing negotiations within Fit for 55, where several directives are expected to be adjusted, will have effects on the industry. Regarding the changes in the electricity network, the price of electricity expects to become more variable, both during the day but also during the year, which is based on a combination of increased electricity use and implementation of intermittent energy sources. To deal with these changes, the pulp and paper industry can see opportunities in contributing to a reduction in energy use, for example by participating in the flexibility market. The existing studies in the field of energy management are not complete as previous research lacks an external perspective. An expanded framework for energy management has been developed, where external monitoring is integrated as an additional key category in an existing model. Moreover, this study presents a model illustrating the distribution of responsibilities for energy-related environmental monitoring, seen from a perspective that includes companies, industry associations, and the EU. To conclude, this study shows that electricity-intensive organizations should formulate internal strategies for how energy-related external environmental monitoring should be implemented and included in energy management.
137

Utilization of Pulp and Paper Waste Products in the Metal Industry : Initial testing of carbon-containing waste material briquettes

Johansson, Ingrid, Deltin, Walter January 2018 (has links)
Today, a huge part of waste products from pulp and paper industries ends up in landfill which is both economically and environmentally adversely. This report examines the possibilities of using those products as a slag foamer and fuel in different furnaces in the metal industry. The waste products contain valuable elements, especially carbon. Therefore, there is an increased interest in finding possible use for the waste products in the metal industry. The reuse would contribute to preservation of energy as fossil fuel can be replaced. In the report, two waste materials called mixed biosludge and fiber reject are examined. The experiments are performed with the waste products pressed together with a base material and cement forming a briquette. The requirements examined are strength needed for both transportation and use in furnaces and ability to create a foaming slag. The results in strength were ambiguous, no waste material based briquettes met the set criteria. As of now, the briquettes are probably not strong enough to be transported. No foaming occurred during the experiment, but only one experiment was performed. Therefore, further experiments are needed before any conclusions can be drawn. The briquettes can possibly replace coke and coal in applications where strength is not as important. Nevertheless, it is uncertain if the briquettes affect the steel quality. / Idag läggs en stor del av restprodukter från pappers och massaindustrin på deponi, vilket innebär såväl ekonomiska som miljömässiga nackdelar. Den här rapporten undersöker möjligheterna att använda dessa restprodukter som slaggskummare och bränsle i de olika ugnarna inom metallindustrin. Restprodukterna innehåller värdefulla ämnen, framförallt kol. Därför finns det ett ökat intresse för att hitta möjliga användningsområden för restprodukterna inom metallindustrin. Denna återanvändning skulle bidra till energibevarande eftersom fossila bränslen kan ersättas. I den här rapporten undersöks två restmaterial, blandat biologiskt slam och fiberavfall. Experimenten utfördes med dessa restprodukter pressade samman med ett basmaterial och cement till en brikett. Kraven som undersöks är styrka för både transport och användning i ugnarna samt förmågan att skumma en slagg. Resultaten för briketternas styrka var tvetydiga, inga av briketterna innehållande restprodukter satisfierade det uppsatta kriteriet. Styrkan är troligtvis för låg för att transport ska vara möjlig. Ingen skumning skedde under experimentet, men endast ett experiment genomfördes. Därför behöver ytterligare experiment genomföras innan några slutsatser kan dras. Men briketterna tros kunna ersätta koks och kol där styrkan inte är viktig. Men det är osäkert om briketterna påverkar stålkvaliteten.
138

Numerical model for estimating greenhouse gas emissions from pulp and paper industrial wastewater treatment systems in Vietnam

Dang, Xuan Hien, Nguyen, Thi Van Anh, Nguyen, Duc Toan, Dang, Thanh Son 05 February 2019 (has links)
At present, it is difficult and costly to measure directly greenhouse gas (GHG) emissions from the wastewater treatment system. Application of model will reduce measurement cost and quickly obtain the forecast data set of GHG emissions. This study developed a mathematical model for both steady and dynamic states to calculate GHG (CO2, CH4, and N2O) emissions from wastewater treatment systems for industrial paper processing. These models are constructed based on mass balance equations of species, including substrate balance equations, biomass balance equations for reactors of treatment systems, stoichiometric coefficiences of species in biochemical reactions and biological processes. The obtained equations were solved based on algorithm of Runge-Kutta and the model was programmed by MATLAB. Results of applying the model to calculate GHG emissions from the paper industrial wastewater treatment system at Bai Bang and Tan Mai plants are as follows: total GHG emissions and emission factor are 3,070.3 kgCO2-eq/day, 0.38 kgCO2- eq/m3, respectively for Bai Bang plant (8,000 m3/day) and 7,413.6 kgCO2-eq/day, 0.74 kgCO2- eq/m3, respectively for Tan Mai plant (10,000 m3/day). The research evaluated a number of influencing factors, such as temperature, flow rate of influent, and substrate concentrations, to GHG emissions at the Tan Mai paper plant. / Hiện nay, việc đo đạc trực tiếp phát thải khí nhà kính (KNK) từ hệ thống xử lý nước thải còn khó khăn và tốn kém. Việc áp dụng mô hình sẽ giảm được chi phí đo đạc và nhanh chóng có được bộ số liệu dự báo một cách tương đối về phát thải KNK. Nghiên cứu đã thiết lập được mô hình toán ở trạng thái ổn định và trạng thái không ổn định để tính toán phát thải khí nhà kính (CO2, CH4, N2O) từ hệ thống xử lý nước thải sản xuất giấy. Các mô hình này dựa trên các phương trình cân bằng chất của các cấu tử bao gồm các phương trình cân bằng cơ chất, các phương trình cân bằng sinh khối trong các bể phản ứng và các hệ số tỷ lượng của các chất tham gia các phản ứng sinh hóa. Các phương trình được giải bằng thuật toán Runge-Kutta và mô hình được lập trình trên ngôn ngữ MATLAB. Mô hình được áp dụng tính toán phát thải khí nhà kính từ hệ thống xử lý nước thải tại nhà máy giấy Bãi Bằng và nhà máy giấy Tân Mai, được kết quả như sau: tổng phát thải khí nhà kính (KNK) và hệ số phát thải là 3.070,3 kg CO2-tđ/ngày, 0,38 kg CO2-tđ/m3 tại Nhà máy giấy Bãi Bằng (8.000 m3/ngày) và 7.413,6 kg CO2-tđ/ngày, 0,74 kg CO2-tđ/m3 nhà máy giấy Tân Mai (10.000 m3/ngày). Nghiên cứu đã đánh giá được một số các yếu tố ảnh hưởng như nhiệt độ, lưu lượng nước thải và nồng độ cơ chất dòng vào đến sự phát thải KNK tại nhà máy giấy Tân Mai.
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Metallförekomst & riskanalys av fiberbanksediment i två ytvatten i Askersund & Jönköping / Metal distribution and risk assessments of the fiberbank sediments in two lakes of the Askersund and Jönköping counties

Fäger, Angelica January 2024 (has links)
Utifrån bakgrundsinformationen har massa- och pappersindustrin varit aktiva under en lång tid utanför Askersund, Aspa Bruk, och Jönköping, Munksjön, innan införande av reningstekniker. Utsläppen av obehandlad fiber och massa tillsammans med metaller som använts av industrierna har lett till bildandet av fiber- och metallrika sediment i recipientvattendragen. Dessa sediment utgör långsiktiga negativa och toxikologiska effekter på växter och djur i den akvatiska miljön. Dessutom har metallerna i de fiberrika sedimenten potential att migrera nedströms i olika utsträckning beroende på lokala miljömässiga faktorer. Det är därav av stor betydelse att utvärdera förekomstmönster och potentiella miljömässiga effekter av metaller i fiberrika sediment. Huvudsyftet var att studera spridningen av metaller och dess potentiella miljömässiga/hälsomässiga effekter i fiberrika sediment inom två halvslutna vattendrag med utlopp i sjön Vättern. Metoden inkluderade mätning av metallkoncentration (genom ett XRF-instrument), glödningsförlust (LOI) och pH mätning av sedimentets porvatten följt av statistisk analys för att undersöka effekterna av pH och organiskt material på koncentration och spridning av metaller. Riskanalys utfördes tillsammans med nationella referensvärden utifrån metoden Svensk Standard tillsammans med effektbaserade tröskelvärden. Resultatet visade att sedimenten i Aspa Bruk hade högre nivåer organiskt material än Munksjön som indikerade en stor input av organiskt material härledda från fiber och/eller massa. Medan ytsedimenten i Aspa Bruk uppvisade högre metallkoncentrationer jämfört med i Munksjön var koncentration av de flesta metallerna (såsom arsenik, bly, koppar, zink, nickel, krom, kobolt och barium) i Munksjöns djupare sediment 60–80 % högre än i Aspa Bruk. En avvikelse sågs för zink vars koncentration var högst vid 3–6 cm i Aspa Bruk. Det framkom även att de högsta koncentrationerna av metall, förutom kobolt och barium förekom vid utkanten av fiberbanken för båda områdena. För båda områdena sågs koncentrationen av kvicksilver, kadmium och kobolt minska signifikant i samband med en ökande nivån organiskt material. Denna trend framkom även för barium och nickel i Munksjön och för zink i Aspa Bruk. Förekomsten och fördelningen av kvicksilver och kadmium observerades påverkas ytterligare av pH. Riskanalysen påvisade att sedimenten i Munksjön var mest förorenade i relation till spridningen. Metallerna med störst negativa effekter och av störst miljöhänsyn i nedåtgående ordning var kvicksilver, bly, koppar, kobolt och zink. / Based on gathered background information, pulp and paper industries have been active for a long time in Askersund, Aspa Bruk, and Jönköping, Munksjön, counties before the introduction of purification techniques. The discharge of untreated fiber and pulp along with metals used by the industries led to the formation of fiber- and metal-rich sediments in recipient watercourses. These sediments pose long-term negative and toxicological effects on the plants and animals in the aquatic environments. Moreover, the metals in the fiber-rich sediments have the potential to migrate downstream to various extents, depending on the local environmental factors. It is thus of great importance to evaluate the distribution pattern and potential environmental effects of metals in fiber-rich sediments. The main purpose was to study the distribution of metals and their potential environmental/health effects in fiber-rich sediments within two semi-enclosed waterbodies draining into the Vättern lake. The method involved measuring metal concentrations (by an XRF-instrument), loss of ignition (LOI), and pH of sediment porewaters, followed by statistical analysis to explore the impacts of pH and organic matter on the concentration and distribution of metals. Risk assessment was performed with national reference values using the standard Swedish method together with effect-based threshold values. The results showed that the sediments in Aspa Bruk had higher values of LOI than those in Munksjön, indicating a larger input of organics derived from fiber and/or pulp to the former. While the surface sediments in Aspa Bruk exhibited higher metal levels compared to Munksjön, the concentrations of most metals (such as arsenic, lead, copper, zinc, nickel, chromium, cobalt, and barium) in Munksjön's subsurface sediments were 60-80% higher than those in Aspa Bruk. A deviation was seen for zinc, whose concentrations were highest at 3-6 cm in Aspa Bruk. It also appeared that the highest concentrations of the metals, except for cobalt and barium, occurred at the edges of the fiberbank in both areas. In both areas, concentrations of mercury, cadmium and cobalt declined significantly with increasing organic matter contents. Such trend was also evident for barium and nickel in Munksjön and zinc in Aspa Bruk. The occurrence and distribution of mercury and cadmium was observed to be affected additionally by pH. Risk assessments revealed that the sediments in Munksjön were most contaminated in relation to the spreading of fiber banks. The metals of the most negative effects and thus environmental concerns, ranked in decreasing order, included mercury, lead, copper, cobalt, and zinc.
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Breaking the chains : A technological and industrial transformation beyond papermaking: Technology management of incumbents

Novotny, Michael January 2016 (has links)
In recent years, the necessity and opportunity for transforming pulp and paper mills into integrative units for large-scale output of biochemicals, biomaterials, and biofuels have come up in discussions of industrial renewal in the Northern hemisphere (mainly in Canada, Sweden and Finland). This transformation is related to technology shifts as well as changing business models based on new bioproducts due to profoundly new market conditions. The aim of this dissertation is to analyse how wood-based biomass industries – with an emphasis on incumbent pulp and paper industries (PPIs) – are managing this industrial and technological transformation that is taking place beyond the papermaking paradigm. Innovation theories on mature industries, their incumbents, and their propensity for technological lock-in and inertia are well-known. How new entrants and incumbents manage these large shifts is seen as central in understanding the dynamics of new, large-scale sustainable technologies on the one hand and the renewal of large, mature process industries on the other. Three research questions are addressed. First, where are the knowledge and technology frontiers developing in this transformation? Second, how are incumbents of PPIs are managing large market and technology shifts based on existing capabilities and knowledge bases? Third, what are the key mechanisms behind the transformation of PPIs from a process-industry perspective? The hermeneutical insights into the system of biomass technologies in general and the PPI industries in particular were gained by using a qualitative case-study approach, which formed the basis for four research articles and for outlining the empirical context and key words search of the quantitative bibliometric methods in a fifth research article. The research findings and main contributions address an identification of the, analytical, “formal”, science-based technology frontiers from a knowledge base perspective.  Old industrialised forest/PPI nations tended to specialize in rather slow growing, forest-based frontiers. They seem to have stayed close to the research trajectories of their woody raw material and knowledge base with the exception of North America. However, this not the entire explanation of transformation and technology development. Chemical pulp mills, in several cases developed into biorefineries, are the nexus of the emerging development block. They are contributing with products in a bioeconomy that is actively moving away from fossils and polluting materials (such as cement, cotton, plastics). In addition, demo plants (potentially nurturing hundreds of bioproducts) that are present at mill sites and involve different stakeholders, can act as the interface between analytical and synthetic knowledge bases that otherwise are difficult to combine in the upscaling phases of process industries. The response of PPI organizations to shifts in both technology and business models is also explained by the concept of diverging innovations of non-assembled products. These are part of a diversification of an industry from a forest industry perspective, and also of a diversification that may enter trajectories of several by-products and side-streams of the pulp “biorefinery” mill, and have analogies to a product-tree and to the material transformation flow of its production systems. But it is also a phenomenon of synergies in a broader multi-sectorial perspective, i.e. new sets of related products/processes that are able to replace industries of non-assembled products under the above-mentioned, new market conditions. The phenomenon of diverging innovations can be regarded as both an empirical contribution – the breaking up of a closed integrated process industry into something new with several emerging and integrative industries as a response to the large shifts in papermaking and sustainable needs in society – and as a theoretical remark on the model for non-assembled products presented by Utterback (1994). / Under de senaste åren har nödvändigheten och möjligheten att omvandla massa- och pappersbruk till integrerade produktionsenheter för storskalig produktion av biokemikalier, biomaterial och biobränslen uppkommit i diskussioner om industriell förnyelse på norra halvklotet - främst i Kanada, Sverige och Finland. Denna omvandling är relaterad till teknikskiften samt förändrade affärsmodeller baserade på nya bioprodukter och kraftigt ändrade marknadsförutsättningar. Syftet med avhandlingen är att analysera hur vedbaserade industrier – med betoning på befintliga massa- och pappersindustrin - hanterar denna industriella och tekniska omvandling utanför det traditionella papperstillverkningsparadigmet. Innovationsteorier om mogna branscher, deras benägenhet för teknisk inlåsning och tröghet är välkända. Hur nya och etablerade aktörer hanterar dessa stora förändringar ses som central för att förstå dynamiken i ny, storskalig, hållbar teknik å ena sidan och förnyelse av mogna processindustrier å andra sidan. Tre forskningsfrågor behandlas. Först, var utvecklas kunskaps- och teknikfronter i denna omvandling? För det andra, hur hanterar etablerade aktörer i massa- och pappersindustrin  stora marknads- och teknologiskiften baserade på befintliga kunskapsbaser? För det tredje, vilka är de huvudmekanismerna bakom omvandlingen av massa- och pappersindustrin ur ett processindustriellt perspektiv? Förståelsen för det biomasseteknologiska systemet i allmänhet och massa- och pappersindustrin i synnerhet erhölls genom att använda kvalitativa fallstudier och metoder. De låg till grund för fyra forskningsartiklar och utmejslade den empiriska kontexten för kvantitativa, bibliometriska metoder i en femte forskningsartikel. Forskningsresultaten utgörs bl a av en identifiering av analytiska, "formella", vetenskapligt baserade teknikfronter. Äldre skogsindustriländer tenderar att specialisera sig i långsamväxande, skogsbaserade teknikfronter. De följer forskningsbanor närmare deras vedråvaru- och kunskapsbaser (med undantag av Nordamerika). Men det är inte hela förklaringen till teknikutvecklingen och dess omställningspotential. Kemiska massabruk, i flera fall utvecklade till bioraffinaderier, kan utgöra hävstången för ett framväxande utvecklingsblock. De bidrar med produkter i en bioekonomi som aktivt rör sig bort från fossila och resursineffektiva material och processer (såsom cement, bomull, plast). Dessutom kan demonstrationsanläggningar härbärgera en storskalig testmiljö för hundratals bioprodukter som är placerade i närheten av massafabriker och som involverar forsknings-, industri- och samhällsintressenter. De kan ävenfungera som gränssnitt mellan analytiska och syntetiska kunskapsbaser som annars är svåra att kombinera i uppskalningsfaser. Massa- och pappersindustrins omvandling förklaras också av begreppet divergerande innovationer av icke-sammansatta produkter. Dessa är delvis en diversifiering av en bransch ur ett skogsindustriellt perspektiv, delvis en diversifiering som kan generera i biprodukter och sidoströmmar, som har analogier med produktträd och påminner om det materiella transformationsflödet i det egna produktionssystemet. Divergerande innovationer kan ge ett synergifenomen ur ett bredare sektoriellt perspektiv, dvs nya uppsättningar av produkter och processer som kan ersätta industrier med icke-sammansatta produkter under de nya marknadsförhållandena som ovan beskrivits. Fenomenet med divergerande innovationer kan betraktas som både ett empiriskt bidrag - att bryta upp en sluten, integrerad processindustri till något nytt med flera framväxande och integrerande näringar som ett svar på de stora förändringarna i industrin och i samhället – och också som en kritik av modellen för icke-sammansatta produkter som tidigare presenterats av Utterback (1994). / <p>QC 20160829</p>

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