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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.
1

Gaseificação de vinhaça em água supercrítica. / Vinasse gasification in supercritical water.

Silva, Soraia Cristina Félix da 29 February 2016 (has links)
A gaseificação utiliza o conteúdo intrínseco de carbonos e hidrogênios das matérias primas sólidas ou líquidas na geração de uma mistura de hidrogênio (H2), monóxido de carbono (CO), dióxido de carbono (CO2) e metano (CH4). Tal mistura pode ser utilizada como matéria prima na síntese de novos produtos ou como combustível. A gaseificação pode ser utilizada no processamento de uma gama variada de produtos, independentemente de suas características ou estado físico. A utilização de biomassa como insumo da gaseificação vem sendo cada vez mais explorada e estudada, já que apresenta benefícios não somente na esfera ambiental, mas também em âmbitos econômicos e sociais. A vinhaça é um subproduto do processo de produção de álcool, que contém grandes concentrações de nutrientes e matéria orgânica em sua composição. A sua utilização hoje está limitada a fertirrigação e a aplicações isoladas em biodigestão e outros, que não são suficientes para o consumo da produção anual crescente do resíduo. Seu uso na gaseificação permitiria o aproveitamento do conteúdo orgânico da mesma e a produção de gases de alto valor agregado. Como a umidade do insumo interfere negativamente na eficiência da gaseificação clássica, a aplicação da mesma para matérias primas com alto teor de líquidos não é recomendada. Uma alternativa viável seria a utilização do meio gaseificante supercrítico, que resulta em rendimentos constantes, independentemente da umidade da corrente de entrada do reator. O presente trabalho consiste no projeto de um módulo de gaseificação de vinhaça em água supercrítica, a ser instalado como uma unidade anexa a usinas de açúcar e álcool. Ele compreende o projeto conceitual e análise de viabilidade deste módulo, incluindo estimativas de CAPEX (Capital Expenditure) e OPEX (Operation Expenditure) e uma análise de sensibilidade dos mesmos. O estudo apresenta ainda o estado da arte do conhecimento e da tecnologia de gaseificação com água supercrítica (SCWG), relacionando os gargalos a serem resolvidos, assim como os ganhos intrínsecos da definição conceitual do projeto. / The gasification process uses the carbon and hydrogen content in a given solid or liquid feedstock to produce a gaseous mixture of hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2) and methane (CH4). This mixture can be used as a precursor in the synthesis of new products or directly as a fuel. The gasification can be used in the processing of a wide range of materials, regardless of its characteristics or physical state. The use of vinasse as a gasification feedstock has been increasingly explored and studied, since its appeal lies not only on the environmental sphere, but as well on economic and social scope. Vinasse is a byproduct of the ethanol/ sugar producing process and contains large concentrations of nutrients and carbon organic matter in its protein-rich composition. The use of this fluid is limited today to fertirrigation and isolated applications, that are not enough for the consumption of its growing production. The possibility of gasifying the vinasse would allow a more profitable use of the fluid. In the classical gasification, the moisture content of the product being gasified impairs the yield of the reaction. So, for liquid feedstock its use is not recommended. One viable alternative for this case would be the use of the supercritical water as a reaction medium, which results in constant yields regardless of the moisture content of the raw material. This work consists on the design of module for vinasse gasification in supercritical water, to be installed as a unit, attached to an alcohol/ sugar plant. It comprises the conceptual design and feasibility study of the module, including CAPEX and OPEX estimates, plus a sensitivity analysis. The study also presents the state of the art of the knowledge associated to SCWG technology, relating bottlenecks to be solved, as well as the intrinsic gains from conceptual design definition.
2

Gaseificação de vinhaça em água supercrítica. / Vinasse gasification in supercritical water.

Soraia Cristina Félix da Silva 29 February 2016 (has links)
A gaseificação utiliza o conteúdo intrínseco de carbonos e hidrogênios das matérias primas sólidas ou líquidas na geração de uma mistura de hidrogênio (H2), monóxido de carbono (CO), dióxido de carbono (CO2) e metano (CH4). Tal mistura pode ser utilizada como matéria prima na síntese de novos produtos ou como combustível. A gaseificação pode ser utilizada no processamento de uma gama variada de produtos, independentemente de suas características ou estado físico. A utilização de biomassa como insumo da gaseificação vem sendo cada vez mais explorada e estudada, já que apresenta benefícios não somente na esfera ambiental, mas também em âmbitos econômicos e sociais. A vinhaça é um subproduto do processo de produção de álcool, que contém grandes concentrações de nutrientes e matéria orgânica em sua composição. A sua utilização hoje está limitada a fertirrigação e a aplicações isoladas em biodigestão e outros, que não são suficientes para o consumo da produção anual crescente do resíduo. Seu uso na gaseificação permitiria o aproveitamento do conteúdo orgânico da mesma e a produção de gases de alto valor agregado. Como a umidade do insumo interfere negativamente na eficiência da gaseificação clássica, a aplicação da mesma para matérias primas com alto teor de líquidos não é recomendada. Uma alternativa viável seria a utilização do meio gaseificante supercrítico, que resulta em rendimentos constantes, independentemente da umidade da corrente de entrada do reator. O presente trabalho consiste no projeto de um módulo de gaseificação de vinhaça em água supercrítica, a ser instalado como uma unidade anexa a usinas de açúcar e álcool. Ele compreende o projeto conceitual e análise de viabilidade deste módulo, incluindo estimativas de CAPEX (Capital Expenditure) e OPEX (Operation Expenditure) e uma análise de sensibilidade dos mesmos. O estudo apresenta ainda o estado da arte do conhecimento e da tecnologia de gaseificação com água supercrítica (SCWG), relacionando os gargalos a serem resolvidos, assim como os ganhos intrínsecos da definição conceitual do projeto. / The gasification process uses the carbon and hydrogen content in a given solid or liquid feedstock to produce a gaseous mixture of hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2) and methane (CH4). This mixture can be used as a precursor in the synthesis of new products or directly as a fuel. The gasification can be used in the processing of a wide range of materials, regardless of its characteristics or physical state. The use of vinasse as a gasification feedstock has been increasingly explored and studied, since its appeal lies not only on the environmental sphere, but as well on economic and social scope. Vinasse is a byproduct of the ethanol/ sugar producing process and contains large concentrations of nutrients and carbon organic matter in its protein-rich composition. The use of this fluid is limited today to fertirrigation and isolated applications, that are not enough for the consumption of its growing production. The possibility of gasifying the vinasse would allow a more profitable use of the fluid. In the classical gasification, the moisture content of the product being gasified impairs the yield of the reaction. So, for liquid feedstock its use is not recommended. One viable alternative for this case would be the use of the supercritical water as a reaction medium, which results in constant yields regardless of the moisture content of the raw material. This work consists on the design of module for vinasse gasification in supercritical water, to be installed as a unit, attached to an alcohol/ sugar plant. It comprises the conceptual design and feasibility study of the module, including CAPEX and OPEX estimates, plus a sensitivity analysis. The study also presents the state of the art of the knowledge associated to SCWG technology, relating bottlenecks to be solved, as well as the intrinsic gains from conceptual design definition.
3

Conception et étude des performances d'une solution auto-configurable pour les réseaux de transport du futur / Design and performances study of a self-configurable solution for future transport networks

Le Quéré, Damien 16 June 2015 (has links)
Dans cette thèse, nous étudions la solution LOCARN : ''Low Opex & Capex Architecture for Resilient Networks''. LOCARN est une architecture de réseaux paquet alternative conçue dans une optique de simplicité de sa structure et ses mécanismes tout en permettant par sa conception la résilience et l'auto-adaptation des services de transport clients. Compte tenu de la complexification croissante des réseaux de transport opérateurs ces dernières décennies, nous prenons ces réseaux comme cas d'usage privilégié. Dans ce cadre, LOCARN permet une simplification considérable des composants et de leur gestion en comparaison des solutions actuelles des opérateurs – ce qui implique respectivement des réductions de CAPEX et d'OPEX. Dans le travail qui suit, nous présentons LOCARN techniquement et mettons en évidence ses intérêts pour les opérateurs par rapport aux autres technologies de transport. Puis, la question prioritaire étant la capacité de mise à l'échelle de LOCARN pour des réseaux de grandes dimensions, nous étudions cette question en détails ce qui nous permet d'établir que l'architecture est tout à fait capable de passer à l'échelle dans des réseaux de transport réalistes. En outre, pour améliorer les performances nous avons également spécifié et évalué deux améliorations de conception permettant à l'architecture de transporter d'un très grand nombre de services, les résultats obtenus sont très encourageants. / In this thesis, we study the LOCARN solution “Low Opex & Capex Architecture for Resilient Networks". LOCARN is an alternative packet network architecture that has been conceived with a special attention to the simplicity of its structure and mechanisms while allowing by design the resiliency and the self-adaptation of clients transportation services. Considering the growing complexification of operators transport networks during the last decades, we consider these latter as the privileged use case. In such a context, LOCARN would allow a drastical simplification of devices and their operation compared to common operator solutions – this involves respectively reductions of CAPEX and OPEX. In this work, we first present LOCARN technically and we bring out its interests for operators beside other transport technologies. Then, since the primary issue of LOCARN is it scalability for large networks, we study this point in details which allow us to establish that the architecture is altogether capable to scale in realistics transport networks. Moreover, to increase the performances we specified two design improvements allowing the architecture to transport a huge amount of clients, the obtained results are very encouraging.
4

Konceptstudie e-metanol i Norra Sverige / Concept study e-methanol in Northern Sweden

Sahlén, Ronja January 2022 (has links)
Användandet av fossila bränslen som energikälla leder till stora utsläpp av växthusgaser och klimatförändringar, vilket börjar bli ett hot som växer sig större för varje år. Genom att använda e-bränslen kan man ersätta fossila bränslen, minska utsläppen av växthusgaser och lyckas uppnå klimatmålen. Examensarbetet specialiserade sig på produktion av e-metanol som är en slutprodukt av e-bränslen. Syftet var att undersöka förutsättningarna för ett ekonomiskt, tekniskt och säkerhetsmässigt hållbart Power-to-X koncept i form av en e-metanolanläggning i Norra Sverige. Detta gjordes genom att ta fram mass- och energibalans för metanolproduktion, dimensionera och genomföra en ekonomisk analys för en e-metanolanläggning. För dimensionering undersöktes metanolbehovet och vad nuvarande konventionella metanolanläggningar producerar. En teknisk kartläggning av e-metanolproduktion och olika elektrolys-tekniker utfördes, för att uppskatta en genomförbar storlek av e-metanolanläggning i Norra Sverige. För examensarbetet utfördes inte en teknisk kartläggning för koldioxidavskiljning, CO2-råvaran valdes att köpas in som en driftskostnad. Ett förenklat flödesschema togs fram med vald PEM-elektrolysteknik och direkt CO2-hydrering baserad på liknande studier inom metanolproduktion. För ekonomiska analysen utvärderades anläggningens totala kapitalinvesteringskostnad och driftskostnad för metanolproduktion och elektrolysör separat. Kostnaden för utrustningen inom metanolproduktionen togs från studier med ett liknande flödesschema. Utrustningen som beaktades var kompressorer, värmeväxlare, reaktor, separator och destillation. Efterfrågan på förnybar metanol i Sverige och resten av världen är stor och förväntas fortsätta att öka, för att användas i flera tusentals vardagsprodukter, inklusive plast, färg, kosmetiska och bränslen. För e-metanolanläggningen krävs det stora mängder el och vatten till elektrolysören och koldioxid för metanolproduktionen. En e-metanolanläggning med 500 kton/år i kapacitet, anses vara fullt genomförbar att realisera i Norra Sverige. Tekniken finns för att kunna skapa den mängd CO2 och H2 som anläggningen kräver. Största svårigheten är att få råvarorna, CO2 och H2, till en rimlig kostnad och kapital för att bygga anläggningen. Vidare är det osäkert ifall det finns tillräckligt med förnybar CO2 från netto CO2-neutrala källor i Norra Sverige. Den totala kapitalkostnaden för denna storlek uppskattades till 1,61 miljarder SEK fördelat på tre konstruktionsår, vilket till största del bestod av kostnaden för elektrolysören med 72 %. Den totala driftskostnaden uppskattades till 1,74 miljarder SEK per år, vilket till största del bestod av kostnaden för elektriciteten med 72 %, där majoriteten gick till elektrolysören. Priset på CO2 har en stor inverkan beroende på val av källa och teknik för koldioxidavskiljning. Dessa kostnader är en uppskattning och kan vara högre för ett verkligt fall, när skatter, plats etc. tas i hänsyn och när elprisets variation är medräknat. E-metanol kan bli konkurrenskraftig med fossil metanol om kostnaden för elektrolysören och elpriset, skulle minska avsevärt och ifall det finns tillräckligt med förnybar CO2 tillgängligt.
5

Processtyrningens påverkan på medarbetares resultat i ett tjänsteföretag / Process managements impact on employee’s performance in a service company

Björck, Johan, Ericson, Carl January 2020 (has links)
Processorientering är en organisationsform som fokuserar på processer istället för hierarkier. Inom organisationsformen processorientering styrs organisationen med processtyrning som innefattar ett antal komponenter som ska ge styreffekter och driva företagets resultat. Tidigare undersökningar inom ämnet granskar organisationsformen i sin helhet och effekterna för organisationen. Det som dock inte tidigare har undersökts är vad denna organisationsform ger för effekter på en grupp medarbetare eller en enskild medarbetare.  Genom att studera detta vill vi erhålla en nyanserad bild och inblick i hur implementeringen av processer påverkar medarbetare i en organisation och hur processtyrning kan bidra till att realisera ett företags mål. Med utgångspunkt från befintlig teori gällande processorientering och dess komponenter har det identifierats tre centrala delar. Dessa centrala delar är prestationen både på medarbetares individuella nivå och företagsnivå, medarbetarnas synsätt och icke-finansiella nyckeltalsindikatorer. En webbaserad enkätundersökning genomfördes där medarbetares upplevelser om processtyrning samlades in. Enkäten delades upp i kategorierna medvetenhet, frekvens, samarbete, påverkan på medarbetare och effekter. Kategoriseringen gjordes med stöd av tidigare studier av processorientering.  Med grund i den teoretiska referensramen har vi analyserat vår data och kunde konstatera att effekterna i vissa fall stämmer väl överens med det från teorin förväntade resultatet och i vissa fall avviker resultatet från teorin. Vår studie bidrar till att utveckla och nyansera modellen för processorientering. Vi vill visa hur medarbetare upplever och hanterar de effekter som olika grader av processorientering kan få samt hur medarbetarnas upplevelser kan påverka företaget i sin helhet vad gäller möjligheten att uppnå sina mål. / Process orientation is a type of organisation that focuses on processes instead of hierarchies. Within the organisational form, the organisation is managed by process management which include several components providing control effects and driving the company's results. A web-based survey was conducted in which employees' experiences about process management were collected. The survey included the categories of awareness, frequency, collaboration, impact on employees and effects. The categorization was developed in line with previous studies of process orientation. Based on the theoretical frame of reference, we have analysed our data and found that in some cases the effects are well in line with the expected effects from the theory and in some cases, these differ from the theory. Our study is a contribution to the work of developing and nuancing the model of process orientation. Our study shows how employees are experiencing and managing the effects of different degrees of process orientation and how employees' experiences can affect the companies’ ability to achieve their goals. As a result, the role of process management is to increase the employee's degree of process orientation.
6

Telecom Infrastructure Sharing as a Strategy for Cost Optimization and Revenue Generation : A Case Study of MTN Nigeria/Zain Nigeria Collocation

Onuzuruike, Emeka January 2009 (has links)
There is a growing need for operators and providers in the Nigerian telecoms industry to drive down cost of capital assets or infrastructure deployed for telecom services. This has been expressed in recent times by many operators who now come, together , on basis of mutual, agreements , to consider sharing infrastructure. The telecom market in Nigeria is driven by growing demand for telecommunications services like voice, SMS, data services like internet, fax, etc as well as high broadband services like video calling, video messaging and video conferencing. This high demand from telecom users combined with the heated competition of a gradually maturing telecoms market in Nigeria has driven many telecoms operators to explore ways of reaching their potential customers in very cost efficient and cost effective ways, hence the need to reduce the cost of rolling out telecom infrastructure while at the same time achieving the numbers through effective network coverage. Also, the regulatory body in Nigeria,NCC( Nigeria Communications Commission) has also given its backing to this initiative by providing the legal and technical guidelines that would ensure fairplay and enhance fair competition. This study or research aims at exploring the value of infrastructure sharing as a means of achieving cost efficiency and revenue assurance. The research is based on a case study analysis of the current collocation arrangement between MTN Nigeria Ltd and Zain Nigeria Ltd. The study seeks to explore the benefits of the infrastructure sharing deal between these two companies as well as recommend an improved or enhanced framework or model to sustain this strategy model in the context of the Nigerian telecommunications industry. Based on a survey/interview of 20 respondents drawn from key departments involved in this sharing deal, the following conclusions were drawn. (1) That both operators have experienced significant reduction in their cost of CAPEX(capital expenditure) employed in network rollouts/deployments; (2) that passive infrastructure(network infrastructure sharing) has led to an improved cost efficiency in network deployments; (3) that infrastructure sharing has led to improved network based operational expenditure; (4) that passive infrastructure sharing has enabled operators achieve improved coverage and capacity; (5) that infrastructure sharing has had no negative impact on customer experience and quality of service; (6) that infrastructure sharing has led to improved service delivery by telecoms operators whereby captial gained or recouped has been invested in product innovations through better value added services to gain competitive advantage. The implications of these findings is that telecom infrastructure sharing serves as an effective business model for cost optimization and revenue generation for telecom operators in Nigeria and the rest of Africa. / +234-8032005495
7

Mudanças estruturais e resultados bancários no mercado de varejo

Rodrigues, Ivanildo de Lima 31 July 2017 (has links)
Submitted by Ivanildo De Lima Rodrigues (ivann.lr@gmail.com) on 2017-08-30T23:54:44Z No. of bitstreams: 1 dissertação ivanildo de lima rodrigues 2017.pdf: 2423285 bytes, checksum: 0bae06eb322828ab600fcf115fd0d9d9 (MD5) / Approved for entry into archive by Joana Martorini (joana.martorini@fgv.br) on 2017-08-30T23:59:09Z (GMT) No. of bitstreams: 1 dissertação ivanildo de lima rodrigues 2017.pdf: 2423285 bytes, checksum: 0bae06eb322828ab600fcf115fd0d9d9 (MD5) / Made available in DSpace on 2017-08-31T13:31:15Z (GMT). No. of bitstreams: 1 dissertação ivanildo de lima rodrigues 2017.pdf: 2423285 bytes, checksum: 0bae06eb322828ab600fcf115fd0d9d9 (MD5) Previous issue date: 2017-07-31 / In the last decade, the financial system has undergone a series of economic and political changes, as well as structural ones, among them the technological modernization as a factor of optimization of processes and of attendance as well as of new services rendered related. The objective of this study is to verify the effectiveness of investing in information technology (T.I.), investigating whether there is an impact on bank efficiency of the results indicator (ROE) of the five largest financial institutions operating in Brazil; That is, how efficient use of technological resources has affected bank results over the last 10 years and how effective resource allocation is in process automation. Using the database used, it was extracted from the Central Bank of Brazil's website, which periodically makes available the quarterly financial statements of the institutions authorized to operate in the country and the financial statements made available by the institutions containing additional data not contemplated by the BACEN. With the use of the Central Bank of Brazil database, regressions were made seeking to identify the profit and loss accounts that best explain the profitability of the banks, among them the sub-accounts contained in administrative expenses called expenses for data processing and communications. Firstly, an essay was made on the evolution of institutions of interest addressing structural changes such as the evolution of the number of self-service terminals, internet banking and mobile, as well as the number of traditional service points and number of employees. Next, the Return on Equity (ROE) indicators were examined, observing their evolution in the period of interest, seeking to identify which factors affected it and ROE, respectively. It was also verified the evolution of CAPEX (Capital Expenditure) and OPEX (Operational Expenditure) in data processing of each institution, although in different approaches. In the end, greater cohesion was identified between private institutions and higher general revenues, with public institutions and foreign participation with more dispersed data, assuming the need for operational and strategic adjustments that are not necessarily due to the volume of investment but rather to the allocation Resources, for example. The most consistent data found, however, were presented in the panel analysis with the most significant effect found between the dependent variable Employees / Asset and the independent variable (CAPEX in data processing). Positive effects of CAPEX on data processing in profitability were also identified. / O sistema financeiro experimentou, na última década, uma série de mudanças econômicas e políticas, além de estruturais, entre elas a modernização tecnológica como fator de otimização de processos e de atendimento bem como de novos serviços prestados relacionados. O trabalho objetiva verificar a efetividade em investir em tecnologia de informação (T.I.) investigando se há impacto no indicador de resultados (ROE) das cinco maiores instituições financeiras atuantes no Brasil; isto é, como a utilização eficiente de recursos tecnológicos afetou, durante os 10 últimos anos, os resultados bancários e o quão eficaz é o direcionamento de recursos em automatização de processos. Com a utilização da base de dados do Banco Central do Brasil, foram feitas regressões procurando identificar as contas do resultado que melhor explicam a lucratividade dos bancos, entre elas as subcontas contidas em despesas administrativas denominadas despesas com processamento de dados e comunicações. Primeiramente, foi feito um ensaio sobre a evolução das instituições de interesse abordando mudanças estruturais como evolução do número de terminais de autoatendimento, internet banking e mobile, bem como o número de pontos de atendimento tradicionais e de funcionários. Em seguida, abordaram-se os indicadores de Retorno sobre o Patrimônio Líquido – ROE, observando-se sua evolução no período de interesse, procurando-se identificar quais fatores o afetaram. Também foi verificada a evolução de CAPEX (Capital Expenditure) e OPEX (Operational Expenditure) em processamento de dados de cada instituição, embora em abordagens distintas. Ao final, foi identificada maior coesão entre as instituições privadas e de maior faturamento geral, ficando as instituições públicas e a de participação estrangeira com dados mais dispersos, pressupondo necessidade de ajustes operacionais e estratégicos que passam não necessariamente pelo volume de investimento, mas pela alocação eficiente desses recursos, por exemplo. Os dados mais consistentes encontrados, no entanto, foram apresentados quando da análise em painel com o efeito mais significativo encontrado entre a variável dependente Funcionários/Ativo e a variável independente (CAPEX em processamento de dados). Também foram identificados efeitos positivos do CAPEX em processamento de dados na lucratividade.
8

Subsea fluid sampling to maximise production asset in offshore field development

Abili, Nimi Inko January 2015 (has links)
The acquisition of representative subsea fluid sampling from offshore field development asset is crucial for the correct evaluation of oil reserves and for the design of subsea production facilities. Due to rising operational expenditures, operators and manufacturers have been working hard to provide systems to enable cost effective subsea fluid sampling solutions. To achieve this, any system has to collect sufficient sample volumes to ensure statistically valid characterisation of the sampled fluids. In executing the research project, various subsea sampling methods used in the offshore industry were examined and ranked using multi criteria decision making; a solution using a remote operated vehicle was selected as the preferred method, to compliment the subsea multiphase flowmeter capability, used to provide well diagnostics to measure individual phases – oil, gas, and water. A mechanistic (compositional fluid tracking) model is employed, using the fluid properties that are equivalent to the production flow stream being measured, to predict reliable reservoir fluid characteristics on the subsea production system. This is applicable even under conditions where significant variations in the reservoir fluid composition occur in transient production operations. The model also adds value in the decision to employ subsea processing in managing water breakthrough as the field matures. This can be achieved through efficient processing of the fluid with separation and boosting delivered to the topside facilities or for water re-injection to the reservoir. The combination of multiphase flowmeter, remote operated vehicle deployed fluid sampling and the mechanistic model provides a balanced approach to reservoir performance monitoring. Therefore, regular and systematic field tailored application of subsea fluid sampling should provide detailed understanding on formation fluid, a basis for accurate prediction of reservoir fluid characteristic, to maximize well production in offshore field development.
9

Desarrollo de modelo de costos de operación de la línea de procesamiento fundición y refinería del cobre para evaluación económica

Cerón Amigo, Sebastián Alejandro January 2019 (has links)
Memoria para optar al título de Ingeniero Civil de Minas / La Vicepresidencia de Proyectos de Codelco está elaborando un modelo completo de evaluación de proyectos para estudios de factibilidad, el que responde a la imperiosa necesidad de estandarizar los protocolos de planificación ya que, debido al carácter público de la empresa, los presupuestos de inversión deben ser aprobados por organismos estatales, lo que se dificulta cuando se solicitan servicios a empresas consultoras privadas, las que utilizan softwares de confusa o compleja trazabilidad de datos y algoritmos, por lo que los proyectos realizados bajo esta metodología han tenido dificultades en la obtención del financiamiento, lo que intrínsecamente retrasa los proyectos. En esta línea, se requiere completar el modelo de evaluación económica diseñando los modelos de costos de fundición y de refinería del cobre, de tal manera de que sean un único estándar de planificación a largo plazo. Se toman como base dos proyectos referentes a la División Chuquicamata: API N15FP15 Desarrollo Fundición Chuquicamata y API N14MS03 Explotación Chuquicamata Subterránea , los que cuentan con la información suficiente para modelar. Se seleccionan los insumos sustanciales y se elaboran los dos modelos OPEX, los que poseen cinco hojas Excel: hoja Inicio, hoja Parámetros, con precios, I/P s y tarifas de todos los insumos, hoja Balance de masa FURE actualizado, hoja OPEX base, con los consumos, dotaciones y costos por operación unitaria y por elemento de gasto y, finalmente, la hoja OPEX calculado, que actualiza los gastos según la corrección monetaria y muestra el indicador final buscado: el costo unitario promedio. El Mantenimiento de la fundición ocupa un cuarto de los costos totales, siendo la energía eléctrica, las remuneraciones y el agua industrial los costos principales. En la refinería, la ER ocupa el 60% de los gastos de la planta, en la que las remuneraciones y la energía eléctrica son los gastos primordiales. El costo unitario promedio de la Fundición Chuquicamata es de 207,95 USD/tms y el de la Refinería es de 9,48 ¢/lb, valores que se encuentran dentro de los valores históricos y proyectados. Se concluye que ambas herramientas logran conformar dos modelos estándar de estimación de costos de operación, ya que contienen un listado de los insumos más importantes, con tarifas, precios e I/P s visibles, y con métodos de cálculo debidamente parametrizados, relacionando factores técnicos y económicos, lo que reduce los inconvenientes a la hora de evaluar los proyectos.
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Grön ammoniak i Norra Sverige : Konceptstudie kring förutsättningar för grön ammoniakproduktion i Norra Sverige / Green ammonia in northern Sweden

Hägglund, Fredrik January 2022 (has links)
Europeiska Unionen presenterade den 8 juni 2020 sin vätgasstrategi i syfte för att minska koldioxidutsläppen. Det unionen vill uppnå med sin vätgasstrategi är att uttnytja konceptet Power-to-X där elektricitet omvandlas till energi. Om elektricitetkällan kommer från förnyelsebar energi kommer grön vätgas produceras. Problemet med vätgas idag är lagring, transport och hanteringstrukturen för ämnet men vätgas kan lagras i flertal applikationer. En av de mest lovande lagringsalternativen är ammoniak som bildas när vätgas med kvävgas reagerar med varandra via ammoniaksyntes. Eftersom vätgasproduktionen idag använder fossila bränslen kommer även dess applikation göra det, men med grön vätgas kommer dess applikation även att bli grön. Idag står ammoniakproduktion för 2 % av fossilbränsleanvändning globalt och frigör mer än 400 miljoner ton CO2 årligen. Dessa utsläpp skulle försvinna om produktionen av ammoniak gjordes med Power-to-X konceptet. Syftet med detta examensarbete är att undersöka förutsättningarna ur ett ekonomiskt, tekniskt och säkerhetsmässigt hållbart Power-to-X koncept i form av en Grön Ammoniakanläggning i Norra Sverige. Det innebär att processer för en ammoniakproduktion skall analyseras ur ett teknisk synvinkel där fokus på funktion mot grön ammoniak är i fokus. Den ekonomiska synvinkeln innebär vad kapitalkostnaden (CAPEX) blir för anläggningen samt driftkostnaden (OPEX) som processen får. Arbetet innehåller först en analys av de processer som krävs för att kunna producera ammoniak. Därefter en analys över möjliga tekniker för dessa processer, hur väl de fungerar mot grön ammoniak och vilka antaganden som är i detta arbete. Anläggningen skulle vara storskalig vilket innebär en produktion på 500 ton NH3 $/dag. Det är även antaget en kontinuerlig eltillförsel samt att elnät redan är tillgänglig. Detta gav att vätgasproduktionen gjordes med en PEM-elektrolys, där kvävgas fås från kryogen destillation och ammoniak produceras med HB-processen. Resultatet visades att anläggningens CAPEX och OPEX blev 2 820 MSEK respektive 1 272 MSEK/år. Den dominerande faktorn för kapitalkostnaden var för vätgasproduktion som utgjorde 60 % av CAPEX. Den höga kostnaden för PEM-elektrolys är dels för att utvecklingen av processen inte är fullbordad, där utvecklingen för tekniken skulle kunna ge en stor kostnadsreducering. Det elbehov som anläggningen kräver är 1,6 TWh och och utgör en påverkan på OPEX är 55,4 %. Den process som kräver mest energi är vätgasproduktionen vilket omfattar 94 % av hela anläggningens totala elbehov. En stor anledning till de dyra driftkostnaderna är elpriset. I detta arbete valdes elpriset till ett medelvärde för SE1 i Sverige under en 10 års period. I ett verkligt scenario hade vätgasproduktionen kunnat optimeras för uppnå billigare drift.

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