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Post Production Heavy Oil Operations: A Case for Partial UpgradingLokhandwala, Taher 14 March 2013 (has links)
The transportation of heavy oil is a pressing problem. Various methods have been devised to mitigate the reluctance to flow of these highly dense and viscous oils. This study is focused on evaluating a case for post-production partial upgrading of heavy oil. Specifically, we analyze the impact of visbreaking, a mild thermal cracking method, on the economic and energy demands of the post-production process.
Using conservative modeling techniques and principles we find significant cost and energy savings can potentially result out of visbreaking. Cost savings result as a consequence of reduced diluent usage. Even the most conservative modeling scenario under consideration exhibits significant cost savings in the form of reduced diluent usage; these savings not only offset operational costs but provide short payback periods on capital expenditures. Additionally, the lower gravity blend resulting from visbreaking can also bring about energy and cost savings in pipeline transportation and positively impact the heavy oil value chain from the producer to a refinery or regional upgrading facility.
From this basic analysis of the potential of visbreaking, we can recommend investing resources to study its viability in the field. Using this analysis as a tipping off point and with a detailed look at the chemistry of the oil in question it is possible to make a very viable case for visbreaking. In a similar vein, this analysis can serve as a guide in making a case for other partial upgrading methods as well.
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Supply chain scheduling with delivery costsZhang, Rui 04 1900 (has links)
<p> Supply chain management has been one of the most important issues in manufacturing
industries. In order to improve customer satisfaction, suppliers usually
extend their inbound production operations to outbound logistics operations. To improve
the overall operational performance, it is necessary to study scheduling models
which consider inbound production and outbound deliveries simultaneously. This
thesis deals with supply chain problems on the operational level using deterministic
models. </p> <p> Meeting due dates is always one of the most important concerns in scheduling
and supply chain management. In most supplying contracts, customers require that
suppliers either meet contracted due dates or pay tardiness penalties. In order to
save delivery costs, suppliers usually deliver jobs in batches. Therefore, we will study
supply chain scheduling problems with delivery costs, where our goal is to minimize
the sum of the weighted number of tardy jobs and the batch-delivery costs on a single
machine. </p> <p> In traditional manufacturing system, due dates are not considered as given by
exogenous decisions. In modern supply chains, however, due dates are determined
by taking into account the system's ability to meet the assigned due dates, which
can be quoted with certain costs. Therefore, we will study supply chain scheduling
problems with delivery costs and due date assignment, where our goal is to minimize
the sum of the weighted number of tardy jobs, the due-date-assignment costs and the
batch-delivery costs on a single machine. </p> <p> As we know, most machine scheduling models are intractable in terms of computational
complexity. Therefore, for our above problems, which are even harder, we
first prove their computational complexity. Then we propose pseudo-polynomial algorithms
for optimal solutions. For some problems, the pseudo-polynomial algorithms
perform in polynomial time for some special cases. Finally, we develop efficient approximation
algorithms or fully polynomial time approximation schemes, which can
be implemented easily in practice. </p> / Thesis / Doctor of Philosophy (PhD)
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Edukativni i opšti model kritičnih protoka materijala PD - Precedence Diagramming Structure / The Educative and General Model of the Critical Material Flows, PDM-Precedence Diagramming StructureLetić Duško 06 May 1996 (has links)
<p>Rad,Edukativni i opšti model kritičnih protoka materijala PD - Precedence Diagramming Structure, predstavlja integralni deo teorijskih i eksperimentalnih istraživanja vezanih za razvoj stohastičkih mreža PD-modela iz operacionih istraživanja, kao i modela za odgovarajuću edukaciju kadrova iz oblasti mrežnog upravljanja tokovima materijala u mašinogradnji. U tom smislu u radu su razvijeni i rešavani, putem analitičkih i numeričkih metoda, sledeći modeli:</p><ul><li>Mrežni PD-model sa jednim kritičnim tokom.</li><li>Mrežni PD-model sa isključivo autonomnim (paralelnim) kritičnim tokovima.</li><li>Opšti model sa varijantom kritičnih tokova autonomno-unijatnog tipa.</li><li>Edukativni model za efikasno rešavanje postavljenih problema upravljanjatokovima materijala u pojedinačnoj proizvodnji.</li><li>Modeli za vrednovanje metoda i postupaka iz ovih oblasti operacionih istraživanja, kao i samog edukativnog modela, na bazi razvijenih kvantitativnih i kvalitativnih kriterijuma.</li></ul><p>Ovim istraživanjem stvorene su određene podloge za dalji rad u predmetnom području, posebno sa stanovišta neinvesticionog povećanja efekata materijalne proizvodnje, putem primene razvijenih opercionih modela i edukativnih metoda za njihovo rešavanje.</p> / <p>The paper "THE EDUCATIVE AND GENERAL MODEL OF THE CRITICAL MATERIAL FLOWS, PD-PRECEDENCE DIAGRAMMING STRUCTURE" makes the integral part bof the theoretical and experimental researches connected for the development of the stochastic network PD - models of the opertions research, as well the models for the appropriote personal cadres edu cation in the field of network control of materijal flows in production of machinery. In the paper are also developed and solved, by analytic and numeric methods, the next models:</p><p>* The network PD-model with one critical flow.</p><p>* The network PD-model with excusively autonomus (parallel) critical flows.</p><p>* The general model with the variant of the critical flows of the autonomus -uniate type.</p><p>* The educative model for the effective solving of the stated problems of the material flows control in isolated production.</p><p>* The models and methods valuation of these fields of the operations researches, as well the educative model itself on the basic of the developed quantative and qualitative criteria.</p><p>With these researches are created the defined bases for further work in the subject field, particularly from the attitude of the noninvestment increasing of the effects of the materijal production, using the developed operations models and the educative models for their solving.</p>
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Desenvolvimento de uma sistemática de melhoria do desempenho econômico de indústrias extrativas : o caso de uma mineração a céu aberto / Development of a systematic of economic performance improvement of Extractive Industries – the case of an open-pit miningSchäfer, Fábio January 2012 (has links)
Em função da globalização, os ambientes empresariais estão se tornando mais competitivos; assim, aumenta a preocupação e a necessidade de se prover um sistema de informações gerenciais que seja eficaz, confiável e relevante para auxiliar os gestores a tomarem decisões inteligentes. Com a utilização de princípios e métodos de custeio vinculados aos serviços inerentes aos métodos e operações de lavra, este trabalho tem como primeiro objetivo identificar e compreender as deficiências dos atuais sistemas de custeio e de produção e estruturar uma sistemática que apoie a avaliação do desempenho econômico-financeiro nas minerações a céu aberto. O segundo objetivo deste trabalho é utilizar o método do custo-padrão vinculado à produção e às regras de negócio e validá-lo mediante a comparação do realizado versus previsto nas minerações a céu aberto, através da utilização de conceitos de desperdícios, do princípio do custeio por absorção parcial, do controle e gestão de custos e de produção para avaliação de resultados. A unidade de extração mineral estudada utiliza o método de lavra por bancadas em cava e terceiriza as operações de descobertura, perfuração, detonação, escavação, carregamento e transporte. A empresa contratada utiliza o princípio de custeio por absorção total e o método de custeio de centros de custos. Assim, a sistemática que apoia a avaliação do desempenho econômico-financeiro juntamente com o método do custo-padrão foi validada e desenvolvida em três serviços terceirizados com o objetivo de verificar a sua funcionalidade e a sua praticidade. Portanto, as novas informações gerenciais auxiliam o gestor identificar a produtividade e a lucratividade do empreendimento e os resultados dos serviços e de suas operações, além de todos os custos gerenciais já existentes. / In the light of globalization, the enterprise environments are becoming more competitive; thus, increases the concern and the need to provide a management information system that is effective, reliable and relevant to assist managers to make intelligent decisions. With the use of principles and costing methods linked to services inherent in mining operations and methods, this work is intended mainly identify and understand the weaknesses of the current costing and production system and structure a systematic that supports performance evaluation productive-economic-financial in surface mining. The second objective of this work is to use standard cost method linked to production and business rules and validate it by comparing the accomplished against foreseen in surface mining, through the use of concepts of wastes, the principle costing of partial absorption, cost control and management for production to evaluation of results. The mineral extraction unit studied uses the open pit mining method and outsources the mining operations of pre stripping, drilling, blasting, rock excavation, loading and transportation. The outsourced company uses the costing principle of total absorption and the costing method is the cost centers. Thus, the systematic that support the evaluation of productive-economic-financial performance and the standard cost method were developed and validated in three outsourced services with the goal of verifying its functionality and practicality. Therefore, the new management information assists the manager to identify the productivity and profitability of the enterprise and the results of its operations and services, in addition to all of the existing management costs.
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Desenvolvimento de uma sistemática de melhoria do desempenho econômico de indústrias extrativas : o caso de uma mineração a céu aberto / Development of a systematic of economic performance improvement of Extractive Industries – the case of an open-pit miningSchäfer, Fábio January 2012 (has links)
Em função da globalização, os ambientes empresariais estão se tornando mais competitivos; assim, aumenta a preocupação e a necessidade de se prover um sistema de informações gerenciais que seja eficaz, confiável e relevante para auxiliar os gestores a tomarem decisões inteligentes. Com a utilização de princípios e métodos de custeio vinculados aos serviços inerentes aos métodos e operações de lavra, este trabalho tem como primeiro objetivo identificar e compreender as deficiências dos atuais sistemas de custeio e de produção e estruturar uma sistemática que apoie a avaliação do desempenho econômico-financeiro nas minerações a céu aberto. O segundo objetivo deste trabalho é utilizar o método do custo-padrão vinculado à produção e às regras de negócio e validá-lo mediante a comparação do realizado versus previsto nas minerações a céu aberto, através da utilização de conceitos de desperdícios, do princípio do custeio por absorção parcial, do controle e gestão de custos e de produção para avaliação de resultados. A unidade de extração mineral estudada utiliza o método de lavra por bancadas em cava e terceiriza as operações de descobertura, perfuração, detonação, escavação, carregamento e transporte. A empresa contratada utiliza o princípio de custeio por absorção total e o método de custeio de centros de custos. Assim, a sistemática que apoia a avaliação do desempenho econômico-financeiro juntamente com o método do custo-padrão foi validada e desenvolvida em três serviços terceirizados com o objetivo de verificar a sua funcionalidade e a sua praticidade. Portanto, as novas informações gerenciais auxiliam o gestor identificar a produtividade e a lucratividade do empreendimento e os resultados dos serviços e de suas operações, além de todos os custos gerenciais já existentes. / In the light of globalization, the enterprise environments are becoming more competitive; thus, increases the concern and the need to provide a management information system that is effective, reliable and relevant to assist managers to make intelligent decisions. With the use of principles and costing methods linked to services inherent in mining operations and methods, this work is intended mainly identify and understand the weaknesses of the current costing and production system and structure a systematic that supports performance evaluation productive-economic-financial in surface mining. The second objective of this work is to use standard cost method linked to production and business rules and validate it by comparing the accomplished against foreseen in surface mining, through the use of concepts of wastes, the principle costing of partial absorption, cost control and management for production to evaluation of results. The mineral extraction unit studied uses the open pit mining method and outsources the mining operations of pre stripping, drilling, blasting, rock excavation, loading and transportation. The outsourced company uses the costing principle of total absorption and the costing method is the cost centers. Thus, the systematic that support the evaluation of productive-economic-financial performance and the standard cost method were developed and validated in three outsourced services with the goal of verifying its functionality and practicality. Therefore, the new management information assists the manager to identify the productivity and profitability of the enterprise and the results of its operations and services, in addition to all of the existing management costs.
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Desenvolvimento de uma sistemática de melhoria do desempenho econômico de indústrias extrativas : o caso de uma mineração a céu aberto / Development of a systematic of economic performance improvement of Extractive Industries – the case of an open-pit miningSchäfer, Fábio January 2012 (has links)
Em função da globalização, os ambientes empresariais estão se tornando mais competitivos; assim, aumenta a preocupação e a necessidade de se prover um sistema de informações gerenciais que seja eficaz, confiável e relevante para auxiliar os gestores a tomarem decisões inteligentes. Com a utilização de princípios e métodos de custeio vinculados aos serviços inerentes aos métodos e operações de lavra, este trabalho tem como primeiro objetivo identificar e compreender as deficiências dos atuais sistemas de custeio e de produção e estruturar uma sistemática que apoie a avaliação do desempenho econômico-financeiro nas minerações a céu aberto. O segundo objetivo deste trabalho é utilizar o método do custo-padrão vinculado à produção e às regras de negócio e validá-lo mediante a comparação do realizado versus previsto nas minerações a céu aberto, através da utilização de conceitos de desperdícios, do princípio do custeio por absorção parcial, do controle e gestão de custos e de produção para avaliação de resultados. A unidade de extração mineral estudada utiliza o método de lavra por bancadas em cava e terceiriza as operações de descobertura, perfuração, detonação, escavação, carregamento e transporte. A empresa contratada utiliza o princípio de custeio por absorção total e o método de custeio de centros de custos. Assim, a sistemática que apoia a avaliação do desempenho econômico-financeiro juntamente com o método do custo-padrão foi validada e desenvolvida em três serviços terceirizados com o objetivo de verificar a sua funcionalidade e a sua praticidade. Portanto, as novas informações gerenciais auxiliam o gestor identificar a produtividade e a lucratividade do empreendimento e os resultados dos serviços e de suas operações, além de todos os custos gerenciais já existentes. / In the light of globalization, the enterprise environments are becoming more competitive; thus, increases the concern and the need to provide a management information system that is effective, reliable and relevant to assist managers to make intelligent decisions. With the use of principles and costing methods linked to services inherent in mining operations and methods, this work is intended mainly identify and understand the weaknesses of the current costing and production system and structure a systematic that supports performance evaluation productive-economic-financial in surface mining. The second objective of this work is to use standard cost method linked to production and business rules and validate it by comparing the accomplished against foreseen in surface mining, through the use of concepts of wastes, the principle costing of partial absorption, cost control and management for production to evaluation of results. The mineral extraction unit studied uses the open pit mining method and outsources the mining operations of pre stripping, drilling, blasting, rock excavation, loading and transportation. The outsourced company uses the costing principle of total absorption and the costing method is the cost centers. Thus, the systematic that support the evaluation of productive-economic-financial performance and the standard cost method were developed and validated in three outsourced services with the goal of verifying its functionality and practicality. Therefore, the new management information assists the manager to identify the productivity and profitability of the enterprise and the results of its operations and services, in addition to all of the existing management costs.
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Evaluating Leachability of Residual Solids Generated from Unconventional Shale Gas Production Operations in Marcellus ShaleSharma, Shekar 17 September 2014 (has links)
Hydraulic fracturing operations utilized for shale gas production result in the generation of a large volume of flowback and produced water that contain suspended material, salts, hydrocarbons, metals, chemical additives, and naturally-occurring radioactive material. The water is impounded at drilling sites or treated off-site, resulting in significant generation of residual solids. These are either buried on site or are disposed in lined landfills. The objective of this study was to determine the levels of heavy metals and other elements of concern that will leach from these residual solids when placed in typical disposal environments.
For this purpose, laboratory leaching experiments were employed wherein representative samples were brought into contact with a liquid to determine the constituents that would be leached by the liquid and potentially released into the environment. The samples used included sludge resulting from the physicochemical treatment of process water (TS), sludge solidified with cement kiln dust (SS), raw solids obtained by gravity separation of process water (RS), and drilling mud (DM). The samples were subjected to both single extraction (i.e. Shake Extraction Test, SET) and multiple extraction (i.e. Immersion Test, IT) leaching tests. For the shake extraction test, samples were mixed with a specific amount of leaching solution without renewal over a short time period. In the immersion test, samples were immersed in a specific amount of leaching solution that was periodically renewed over a longer period of time. For both these tests, analyses were performed on the filtered eluate. The tests were performed as per standards with modifications. Distilled de-ionized water, synthetic acid rain (pH ~ 4.2), weak acetic acid (pH ~ 2.88), and synthetic landfill leachate were used as leaching solutions to mimic specific disposal environments.
Alkali metals (Li, K, Na), alkaline earth metals (Ba, Ca, Mg, Sr) and a halide (Br), which are typically associated with Marcellus shale and produced waters, leached at high concentrations from most of the residual solids sample. The SS sample, due to its stabilization with CKD, had a lower extraction efficiency as compared to the unconsolidated TS and RS samples. In EF 2.9 and EF SLL, the leaching took place under acidic conditions, while for EF DDI and EF 4.2, the leaching occurred in alkaline conditions. EF 2.9 and EF SLL were determined to be the most aggressive leaching solutions, causing the maximum solubility of most inorganic elements. Thus, high amounts of most EOCs may leach from these residual solids in MSW landfills disposed under co-disposal conditions. Agitation, pH and composition of the leaching solution were determined to be important variables in evaluating the leaching potential of a sample.
The results of this study should help with the design of further research experiments being undertaken to develop environmentally responsible management/disposal strategies for these residual solids and also prove useful for regulatory authorities in their efforts to develop specific guidelines for the disposal of residuals from shale gas production operations. / Master of Science
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