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Ho, Arthur Yau Wing. "Liquefied Natural Gas Vaporization Terminal." Thesis, The University of Arizona, 2010. http://hdl.handle.net/10150/146034.
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The goal of the enclosed project was to design a liquefied natural gas (LNG) receiving terminal that can deliver 1050 MM SCF per day of natural gas to various consumers. [1.] Liquefied natural gas is first imported from third world nations such as Algeria at S4.50 per MM Btu [20.], stored and vaporized at the facility, and then sent out through pipelines at a pressure of 1250 psi. This was accomplished through the use of a holding and or unloading unit and a vaporization unit. The same equipment three storage tanks, two suction drums, one compressor, one packed bed condenser, and 16,500 ft of pipes -- are used for both the holding and unloading scenarios. One of the major issues of this terminal is the constant heat leak due to the LNG coming in and stored at a cryogenic temperature of -256 F. All of the pipes have 6 inches of insulation to reduce the heat leak. A portion of the LNG in the storage tanks is boiled off in order to keep the rest of the LNG cold. The packed bed condenser is used to recover LNG from the boil-off gas. Afterwards, the LNG is then sent to the vaporization unit to be vaporized by warm Dynalene HC The Dynalene HC is reheated through an air heat exchanger and an ethylene glycol loop. 10% of the imported LNG will be used for this vaporization unit. The only difference between the holding and unloading scenarios is that during unloading, part of the LNG vaporized due to heat leaks will be cooled via the desuperheater and packed bed condenser and sent back to the ship at -252 F. In the holding scenario, more LNG will have to be circulated to keep the temperature at around -256 F. The vaporized LNG is then sold for S6.50 per MM Btu [20.]. Overall, the project is very profitable. Although the total capital investment is S301 Million, the payback period is 6 years. The NPV is $1,900 million, calculated with an IRR of 26.95%.
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Nuzum, Sean Robert. "Aircraft Thermal Management using Liquefied Natural Gas." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1462460693.
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Manlove, Nellie K. "Safety, environmental, and economic conflicts in siting liquefied natural gas marine terminals." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 75 p, 2009. http://proquest.umi.com/pqdweb?did=1694433041&sid=11&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Mendel-Hartvig, Hannes, and Viktor Flinnkfelt. "What Drives Liquefied Natural Gas Imports in Europe?" Thesis, Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-148529.
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This paper studied the extensive margin (EM) and intensive margin (IM)of liquefied natural gas(LNG) imports in Europe over the period 1996-2015. Two econometric models were used, a prob it estimation for the EM and an OLS for the IM. A time-varying approach was conducted to analyse the stability of the models in the studied time frame. The models were constructed through the application of known determinants of LNG trade as well as new factors that previously was unused in the investigation of LNG trade. The results indicated an overall stable EM, but a highly varying IM over the period. The findings inform that the EM is driven by income, diversification and lower bounds technological development and we found that itis inhibited by pipeline imports, domestic production and higher bounds technological development. The IM is determined by favourable pricing opportunities, lower bounds technological development and the diversification aspect of LNG. IM is negatively affected by domestic natural gas production and the higher bounds of technological development.
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Al-Sobhi, Saad Ali. "Simulation and integration of liquefied natural gas (lng) processes." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2506.
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Aljeeran, Fares. "Conceptual Liquefied Natural Gas (LNG) terminal design for Kuwait." Thesis, Texas A&M University, 2005. http://hdl.handle.net/1969.1/3943.
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This research study investigated a new conceptual design for a modular structural configuration incorporating storage for Liquefied Natural Gas (LNG) within the base of the platform structure. The structure, referred to as a modified gravity base concrete structure (MGBCS), was envisioned specifically to be constructed at a suitable site off the coast of Kuwait. Coastal offshore bathometric information, environmental data and existing data on onshore facilities were examined in the site selection portion of the study. A finite element model of the MGBCS was developed using an industry standard finite element code that allows preliminary sizes of structural models to meet appropriate design codes. A variety of parametric and design load scenarios were investigated. This research tackles some preliminary issues that are adequate for an initial evaluation of the proposed design concept. The proposed design concept needs a lot more scrutiny in order to be sufficiently developed as a concept where it can be confirmed as a truly viable concept and investment. It was confirmed that quartering sea conditions, waves approaching at a 45 degree angle, are the most critical scenarios for the terminal based on maximum values and ranges of shears and moments. In addition, there are several interesting issues in this concept that should be further looked at for this design to be further developed. The limitations of our study must be mitigated in future designs if the proposed design concept is to be carried to the implementation stage.
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Rüster, Sophia. "Vertical Structures in the Global Liquefied Natural Gas Market." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-38831.
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During the last decade, the global liquefied natural gas (LNG) market altered substantially. Significant investments have been realized, traded volumes increased and contracting structures gained in flexibility. Various governance forms co-exist, including the poles of spot market transactions and vertical integration as well as numerous hybrid forms such as long-term contracts, joint ventures, and strategic partnerships. This dissertation empirically investigates, based on transaction cost economics and recent extensions thereof, which motivations drive companies towards the choice of hierarchical governance forms. First, the likelihood of vertical integration and the impact of inter-organizational trust as a shift parameter accounting for differences in the institutional environment are analyzed. Estimation results confirm transaction cost economics by showing that relationship-specific investments in an uncertain environment drive LNG companies to invest in successive stages along the value chain. Furthermore, the
presence of inter-organizational trust increases the likelihood of less hierarchical governance modes. Second, alternative theories of the firm are linked in order to explain the menu of strategic positions recently observed in this dynamic market. Estimation results support the positioning-economizing perspective of the firm. The three strategic choices of target market position, resource profile, and organizational structure are interdependent. Third, the determinants of optimal contract length as a trade-off between the minimization of transaction costs due to repeated bilateral bargaining and the risk of being bound in an inflexible agreement in uncertain environments is discussed. Estimation results show that the presence of high asset specificity results in longer contracts whereas the need for flexibility in today’s LNG market supports shorter agreements. When firms have experience in bilateral trading, contract duration decreases. In addition, countries heavily reliant on natural gas imports via LNG are often willing to forgo some flexibility in favor of supply security. Contracts dedicated to competitive downstream markets on average are shorter than those concluded with customers in non-liberalized importing countries.
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Marmolejo, Phillip Christian. "An economic analysis of Floating Liquefied Natural Gas (FLNG)." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92193.
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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 67-68).
This report includes a discussion of the potential production of stranded natural gas reserves through the implementation of Floating Liquefied Natural Gas (FLNG) in a world of growing energy demand followed by an analysis of the technology's economic feasibility. The economic analysis aims to use production and expense estimates related to Shell's Prelude FLNG project in order to determine the project's FOB breakeven price. The net present value (NPV) of the project's discounted future cash flows is used to determine this breakeven price. The results of the economic analysis revealed the FOB breakeven price of Shell's Prelude project to be $8.16 per MMBTU, a reasonable calculation given current breakeven price estimates for similar projects in the area. Even with a 15% error band in Shell's production estimates, the breakeven price remained in the range of $8-$9 per MMBTU. However, when the production of lean natural gas was considered, the breakeven price exceeded $12 per MMBTU, a price that is, based upon current forecasts, too high to warrant consideration of such a project. It was found that with production incentives, such as LPG and condensate, the current FLNG design can prove to be economically successful, given the current LNG price forecasts. However, for the production of stranded reserves lacking these production incentives, a separate lean FLNG design should be considered.
by Phillip Christian Marmolejo.
S.B.
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Migliore, Cappello Calogero. "Modelling the weathering process of stored liquefied natural gas (LNG)." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/33295.
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Weathering occurs in stored liquefied natural gas (LNG) due to the removal of the boil-off gas (BOG) from the LNG container and results in the remaining LNG being richer in heavier components. A model has been developed to predict stored LNG weathering in containment tanks, typically used in regasification. The model integrates a vapour-liquid equilibrium model, and a realistic heat transfer model. It provides a number of advances on previously developed models: (i) heat ingress is calculated based on outside temperature and LNG composition, allowing for daily/seasonal variations; (ii) boil-off-ratio is not an input; (iii) LNG density is estimated using an experimentally based correlation. The model was validated using real industry data and the agreement obtained in predicting overall composition, density and amount vaporized was within industry requirements. Two modelling approaches have been developed: (i) assuming thermodynamic equilibrium between vapour and liquid; and (ii) assuming heat exchange between the two phases. Both models were run in a predictive mode to assess the BOG under different scenarios. One of the main results of this work is that the BOG generation is 25% less when considering the non-equilibrium approach, which will have a significant impact on industry where simple equilibrium models are used. In the initial stages of weathering nitrogen content of LNG has a marked effect on BOG generation. Even 0.5% mol of nitrogen leads to nearly 7% BOG decrease, making the initial BOG unmarketable. That is a result of preferential evaporation of nitrogen and increase in the direct differential molar latent heat. In the final stages of weathering the heavier hydrocarbons govern the BOG dynamics, which becomes a strong function of initial composition and the LNG remaining in the tank.
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Craig, Ian. "Seawater intake risers for Floating Liquefied Natural Gas (FLNG) vessels." Thesis, University of Sunderland, 2018. http://sure.sunderland.ac.uk/10129/.
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As the world energy demand increases, and the desire for cleaner fuels strengthens, a number of major oil and gas companies are developing Floating Liquefied Natural Gas (FLNG) vessels to harvest natural gas ‘stranded’ in reservoirs that have previously been considered too uneconomic to develop. A key requirement for this new generation of vessels is a high volume of low temperature seawater for process cooling. The aim of this research is to investigate whether the concepts underpinning free hanging cantilever seawater intake risers used on Floating, Production, Storage and Offloading (FPSO) vessels can be extended to the design of seawater intake risers for FLNG vessels in order to reach and import colder seawater from depths greater than has so far been achieved with these systems. The research focusses on establishing the physical, mechanical and fatigue properties of a number of material elements under consideration for this application and then investigates a number of combinations to determine the optimum configuration for a hybrid deep seawater intake riser. To demonstrate the strength and fatigue capabilities of the hybrid riser, the selected configuration is then subject to a more detailed analysis with consideration of a number of key aspects such as vessel motion, marine growth, vortex induced vibration, stability due to internal flow and excursion due to external fluid. A number of sensitivities are also performed with respect to riser damping, riser length, vessel size and geographical location. Additionally, the flow characteristics in terms of pressure loss and temperature gain are examined and a number of sensitivities performed to show that the cold seawater can be imported effectively. Finally, using published data for FLNG vessels currently under construction, an economic argument is presented to highlight the potential cost advantage of reaching and importing colder seawater by means of a deep seawater intake riser. As a result of this research, the solution being presented offers a significant technological advantage for these systems in the field enabling high volumes of seawater to be imported from greater depths whilst accommodating the loads induced by the environmental conditions and minimising the loads induced into the hull of the vessel. Furthermore, the solution is based on the concepts of a field proven system, thereby limiting the risks associated with untested technological advancements. The findings of this research enable the process efficiencies of FLNG vessels to be greatly enhanced thus contributing to the more efficient extraction of a cleaner fuel which, in a world with ever increasing energy demands, is critical to the global economy. The novelty of the research is demonstrated by two successful patent applications, one in relation to the improved features of existing seawater intake riser systems and the other in relation to the use of multiple material elements for a hybrid seawater intake riser. Both patents have been examined and granted in five jurisdictions, namely, Europe, Japan, China. South Korea and the USA.
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Fazlollahi, Farhad. "Dynamic Liquefied Natural Gas (LNG) Processing with Energy Storage Applications." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/5956.
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The cryogenic carbon capture™ (CCC) process provides energy- and cost-efficient carbon capture and can be configured to provide an energy storage system using an open-loop natural gas (NG) refrigeration system, which is called energy storing cryogenic carbon capture (CCC-ES™). This investigation focuses on the transient operation and especially on the dynamic response of this energy storage system and explores its efficiency, effectiveness, design, and operation. This investigation included four tasks.The first task explores the steady-state design of four different natural gas liquefaction processes simulated by Aspen HYSYS. These processes differ from traditional LNG process in that the CCC process vaporizes the LNG and the cold vapors return through the LNG heat exchangers, exchanging sensible heat with the incoming flows. The comparisons include costs and energy performance with individually optimized processes, each operating at three operating conditions: energy storage, energy recovery, and balanced operation. The second task examines steady-state and transient models and optimization of natural gas liquefaction using Aspen HYSYS. Steady-state exergy and heat exchanger efficiency analyses characterize the performance of several potential systems. Transient analyses of the optimal steady-state model produced most of the results discussed here. The third task explores transient Aspen HYSYS modeling and optimization of two natural gas liquefaction processes and identifies the rate-limiting process components during load variations. Novel flowrate variations included in this investigation drive transient responses of all units, especially compressors and heat exchangers. Model-predictive controls (MPC) effectively manages such heat exchangers and compares favorably with results using traditional controls. The last task shows how an unprocessed natural gas (NG) pretreatment system can remove more than 90% of the CO2 from NG with CCC technology using Aspen Plus simulations and experimental data. This task shows how CCC-based technology can treat NG streams to prepare them for LNG use. Data from an experimental bench-scale apparatus verify simulation results. Simulated results on carbon (CO2) capture qualitatively and quantitatively agree with experimental results as a function of feedstock properties.
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Sun, Biao. "Numerical simulation on dense gas dispersion and fire characteristics after liquefied natural gas release." Thesis, Curtin University, 2012. http://hdl.handle.net/20.500.11937/2129.
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This PhD dissertation mainly studies the prediction, simulation and mitigation methods of the two main hazards in LNG (Liquefied Natural Gas) industry, LNG vapor dense gas dispersion and LNG fire radiation, respectively. For industrial application purpose, integral model and solid flame model of vapor dispersion and fire radiation, respectively are researched and suggested for using. For complicated scenarios or mitigation measures applied, CFD (Computational Fluid Dynamics) models are studies on the two main accidents.
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Muir, L. J. "Simulation and control system design for a liquefied natural gas vaporiser." Thesis, University of Strathclyde, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381717.
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Timchenko, D. V., and Y. S. Krutas. "Assessment of surface crack strength for storage of liquefied natural gas." Thesis, Sumy State University, 2017. http://essuir.sumdu.edu.ua/handle/123456789/65270.
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The main element of any tank is its housing. The housing of the tank isolates work environment,being subjected to its chemical exposure, it sees mechanical and thermal loads as well. Therefore, the reliability of the tank depends on the reliability of its case. The main characteristic of the reliability of housing is its strength. Loss of tank strength leads to its destruction, the consequence may be large economic losses, environmental pollution and damage to human life.
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Nikhalat-Jahromi, Hamed. "An operational model for liquefied natural gas spot and arbitrage sales." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/14634.
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As more buyers become interested in the spot purchase of liquefied natural gas (LNG), the share of spot trade in LNG business increases. This means that the cash flowing into the upstream of LNG projects is a combination of that generated by deliveries to long-term contract (LTC) customers and uncommitted product and arbitrage spot sales. LTC cash flows are more predictable while uncommitted product and arbitrage cash flows, affected by the dynamics of supply and demand, are more volatile and therefore less predictable. In this research, we formulate an inventory routing problem (IRP) which maximizes the profit of an LNG producer with respect to uncommitted product and arbitrage spot sales, and also LTC deliveries at an operational level. Using the model, the importance of arbitrage, interest rates and compounding frequency in profit maximization, and also the significance of interest rates and fluctuation in spot prices in decision-making for spot sales of uncommitted product are studied. It is proven that writing traditional LTCs with relaxed destination clauses which assist in arbitrage is beneficial to the LNG producer. However, in contrast to what was predicted neither the interest rate nor the compounding frequency has any importance in profit maximization when no change of selling strategy is observed. Apart from these, it is shown that there is a trade-off between the expectation of higher spot prices and the inventory and shipping costs in decision-making for spot sales of uncommitted product in the LNG industry. Finally, it is observed that the interest rate can affect the set of decisions on spot sales of uncommitted product, although the importance of such changes in profit remains to be further explored.
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Ankhi, Abida Sultana. "Supply Chain Risk Management of Liquefied Natural Gas (LNG) in Australia." Thesis, Curtin University, 2017. http://hdl.handle.net/20.500.11937/68328.
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This research examines the supply chain risk management of Australia’s Liquefied Natural Gas (LNG) supply chain. The study develops a risk management methodology based on quality function deployment and 0-1 multiobjective optimization model. The research reveals 33 LNG supply chain risks and 30 risk management strategies (RMSs) for Australian LNG supply chain. Optimal sets of RMSs are found using the methodology which would be beneficial for the LNG risk managers in a limited resources scenario.
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Pirie, Sandra Mary. "Design, simulation and control of a flexible LNG reception terminal." Thesis, University of Strathclyde, 1992. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21230.
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This research is a preliminary design study relating to the importation of liquefied natural gas (LNG) in the United Kingdom, focusing on the process design, simulation and control of a flexible LNG reception terminal. The primary operating objective of the proposed LNG reception terminal is to accept a wide variety of LNG feedstocks, and to continuously produce output with consistent specifications. This requirement to provide "feedstock flexibility" was the major influence in the development of this research. The process design was derived from the application of selection criteria to assess the impact of feedstock flexibility on process unit performance. The subsequent dynamic simulation had to represent multiple operating conditions and feedstock changeovers for a multicomponent system. This required the incorporation of an interactive physical properties database and the adoption of a pseudo-binary distillation column model in the simulation. Regulatory control loops were developed and tuned to provide stable operation for all the plant's operating conditions. In order to assess the impact of multiple feedstock conditions, control system performance was evaluated for disturbance rejection and control valve action. A changeover mechanism was developed which enabled successful dynamic simulation of feedstock changeovers. The simulation also identified significant interactions between certain process units in the flowsheet. In conclusion, the primary objective of the supervisory control system would be management of these interactions as opposed to maintenance of product specifications. This work has provided a preliminary flowsheet and a design tool for process and control studies, for a flexible LNG reception terminal. These will enable the design engineer to investigate a range of changes to the process design and to assess their implications for the plant's overall dynamic behaviour.
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Wu, Dien-yeh. "Evaluation of light duty vehicle conversions to natural gas and liquefied petroleum gas : speciated and off-cycle emissions /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Gokhale, Bhushan. "Application of landfill gas as a liquefied natural gas fuel for refuse trucks in Texas." Texas A&M University, 2006. http://hdl.handle.net/1969.1/4704.
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The energy consumption throughout the world has increased substantially over the past
few years and the trend is projected to continue indefinitely. The primary sources of
energy are conventional fuels such as oil, natural gas and coal. The most apparent
negative impacts of these conventional fuels are global warming, poor air-quality, and
adverse health effects. Considering these negative impacts, it is necessary to develop and
use non-conventional sources of energy. Landfill gas (LFG) generated at landfills can
serve as a source of cleaner energy. LFG has substantial energy generation potential and,
if cleaned of certain impurities, can be used for several applications such as electricity
generation and conversion to high Btu gas. This thesis considers another application of
LFG, which consists of using it as a vehicular fuel for refuse trucks. Currently, limited
research has been performed on the development of such a methodology to evaluate the
application of LFG as a vehicular fuel for refuse truck operations.
The purpose of this thesis is to develop a methodology that can be used to evaluate the
use of LFG generated at landfills as a Liquefied Natural Gas (LNG) fuel source for
refuse trucks in Texas. The methodology simulates the gas generation process at a
landfill by using standard models developed by the Environmental Protection Agency.
The operations of a refuse truck fleet are replicated by using generic drive cycles
developed as part of this research. The economic feasibility is evaluated by estimating
the costs required for cleaning the LFG and converting the truck fleet from diesel to
LNG as well as quantifying the benefits obtained due to change in fuel consumption and
emission generation by the refuse trucks. The methodology was applied to a potential landfill in Texas. The results show that the methodology offers an innovative tool that
allows the stakeholders to evaluate the economic feasibility of using LFG for refuse
truck operations. The methodology also provides a flexible framework wherein each
component can be changed or tailored to meet the specific needs of the stakeholders.
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Warren, Richard. "Towards in-situ analysis of liquefied natural gas with near infrared spectroscopy." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246257.
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Briouig, Mohamed. "Risk management in liquefied natural gas ports and marine terminals supply chains." Thesis, University of Plymouth, 2014. http://hdl.handle.net/10026.1/3013.
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Due to its environmental attributes, Liquefied Natural Gas (LNG) as a clean fossil fuel source of energy has witnessed a steady increase in demand worldwide over the last decade. This increase is mainly attributed to higher demand from the power generation sector as well as from domestic and industrial usages .This growing role of LNG among competing energy sources has raised concerns over the safety and security of the LNG chain of production, transport and distribution and its related infrastructure. Within this context, LNG ports and marine terminals, being strategically located at the midstream of the LNG Supply Chain (SC), are further exposed to safety and security risks and represent credible targets for international terrorism. Ensuring uninterrupted, robust and resilient LNG SC requires first, adequate management of safety and security risks in LNG ports and marine terminals. While each discipline of risk, be it safety or security, has received significant attention both in theory and practice, less attention was given to the management of interfaces and shared impacts among LNG Ports safety and security risks which led to the existence of gaps in the risk management (RM) systems of LNG ports and may represent a major source of risk and disruption to LNG ports. This research addresses such gaps which are poorly addressed in the current literature and proposes a holistic and integrated approach to the issues of LNG ports safety and security risks assessment and management. It also aims to model safety and security RM from a SC perspective and examines the relationships and shared impacts among LNG ports safety and security risks in the present context of increased LNG demand worldwide in the post 9/11 terrorism era. A unique combination of multiple methods within port and maritime SCs, including a Delphi survey, quantitative survey, Soft Systems Methodology (SSM) and a focus group expert consultation, is applied to reformulate the prevailing RM approach marked by dichotomy and a disciplinary silo and to propose a more enhanced and holistic approach to safety and security RM. The results of the study confirm that an integrated and holistic approach to the issue of RM in LNG ports and marine terminals is necessary to cost-effectively address safety and security risks and ensure reliable and resilient LNG SCs. Furthermore, a practical framework, in the form of a conceptual model, for LNG ports risks and emergencies management is proposed which integrates all facets of safety and security risks and emergencies management, including risk prevention, mitigation, emergency planning and response and port business continuity. The proposed conceptual model shows how the proposed RM approach can be practically applied in the context of LNG ports in the Middle East and North Africa (MENA) region, as well as in any LNG port worldwide which lacks an integrated approach to risks and emergencies management.
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Nwankwo, Jonathan Emeka. "Gas utilization in Nigeria : an economic comparison of gas-to-liquid and liquefied natural gas technologies / J.E. Nwankwo." Thesis, North-West University, 2008. http://hdl.handle.net/10394/2056.
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Wang, Chin-Cheng E. "Design and analysis of the natural gas storage tank for automobiles." Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1176236134.
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Okafor, Emeka Joachin. "Modelling vaporizing fluid flow through porous media with applications to liquefied natural gas." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/11675.
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The problem of vaporizing flow of liquefied natural gas (LNG) through porous or penetrable media has received very little attention despite its importance in assessing the performance and risk-based safety of large membrane tank LNG ships under barrier leakages. In this work, a fluid flow model is proposed and used to analyse the vaporizing flow behaviour of LNG through soil and glass wool porous materials. Furthermore, a modified vaporizing liquid pool model is implemented and used to examine the problem of vaporizing LNG pool on non-penetrable solid substrates. We employed an explicit, finite difference and a fourth-order Runge-Kutta algorithms coded in FORTRAN to respectively solve the flow and pool models. Both models were successfully verified and validated by comparisons to experimental data, analytical solutions, and to predictions of a commercial software (TOUGH2). Results from the vaporizing flow and pool analyses demonstrate that, for some of the applications considered, the liquid is expected to reach considered threshold depths, seep through the porous layer and contact, contaminate and/or embrittle surrounding natural or engineered systems. For the specific application to LNG cargo containment systems (or cargo tanks), this work has shown that there are safety risks associated with LNG leakage, which are ultra-low temperature of the inner hull, cryogenic damage and subsequent failure of the cargo containment system. Thus, for any LNG membrane cargo containment system to continue to be safe and secure, the various structural members of the insulation system should be designed and equipped with new and improved materials that possesses the necessary mechanical and thermophysical properties to maintain and/or improve the critical temperature standard and low-temperature performance of these systems. Further work should consider additional experimental evidence in order to fully validate and establish that solution predictions by the proposed models are describing the actual physical effects.
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Wang, Jun. "Total Constraint Management for Improving Construction Work Flow in Liquefied Natural Gas Industry." Thesis, Curtin University, 2018. http://hdl.handle.net/20.500.11937/73516.
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Australia has benefited and will continue to benefit significantly from Liquefied Natural Gas (LNG) investments underway. Managing these LNG projects is challenging as they become increasingly complex and technologically demanding. The primary goal of this thesis is to develop a Total Constraint Management (TCM) method to improve construction work flow during LNG construction. Five controlled experiments were conducted and results show that successful implementation of TCM can significantly improve construction productivity and reduce schedule overruns.
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Al-Hajri, Khalid. "A strategy for the commercial development of the liquefied natural gas industry in a country with a large natural gas reserve." Thesis, Robert Gordon University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289096.
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Myrmo, Øystein. "Numerical modeling of pool spreading, heat transfer and evaporation in liquefied natural gas (LNG)." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-13639.
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This master's thesis is a continuation of previous theses written at ComputIT AS. It treats heat transfer to LNG pools boiling on water through two heat transfer models, LNGSIM1 and LNGSIM2. LNGSIM1 utilizes heat transfer correlations for pure liquids in combination with physical data of the mixture, while LNGSIM2 uses LNGSIM1 and a simple model for the concentration boundary layer. Both models are implemented in the CFD software Kameleon FireEx (KFX) and thereafter tested and validated against experimental data from the Burro test series. Comparisons with experimental data show that LNGSIM1 often produces correct trends in the downstream gas concentrations. The results are, however, often shifted in time, indicating that the heat transfer in the beginning of the spill is too low. LNGSIM2 is constructed to increase the heat transfer compared to LNGSIM1, hence vaporizing the LNG faster to better fit the experimental data in time. The choice of the constant CSIM2 in LNGSIM2 greatly affects the heat transfer, and it is found to fit experimental data best for 0.70 < CSIM2 < 0.80.An attempt to approximate LNG as pure methane produced erroneous results due to the heat flux remaining constant throughout the spill. Another attempted approximation was the use of a constant heat transfer coefficient. This produced very low heat fluxes towards the end of the spill, making it impossible for the gas concentrations to reach a zero value within the experimental time interval. The use of these simplifications are therefore not advised.A study of rapid phase transitions (RPT) is conducted using a simple criterion for when an RPT can occur. Comparison with a theoretical study gives promising results for describing when, where and why an RPT occur. This can be used to estimate when to release the pressure wave of an RPT.Investigations of the pool boiling correlations for pure liquids conclude that the way of calculating the transition boiling regime results in too high heat fluxes in that regime. To address this, a parameter study using LNGSIM1 and a factor Z is performed in order to reduce the transition boiling heat fluxes. The optimum values of Z are thereafter combined with the optimum values of CSIM2. Combining Z and CSIM2 reveals that most of the investigated values of Z overrides the wanted effect of CSIM2, hence warranting new approaches to reduce the overestimated transition boiling heat fluxes. Nevertheless, LNGSIM1 and LNGSIM2 with 0.70 < CSIM2 < 1.00 appear to be good alternatives to the current heat transfer model in KFX, since the heat transfer coefficient is continuously calculated based on compositions and boiling regimes, whereas the KFX model requires a constant heat transfer coefficient as input.
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ARAUJO, FELIPE SANTOS. "LOGISTICAL AND ECONOMICAL EVALUATION OF THE USAGE OF LIQUEFIED NATURAL GAS IN TWO INDUSTRIAL." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12316@1.
Full textAbstract:
Esta dissertação apresenta dois estudos de caso de
Plantas
Industriais que
atualmente utilizam Óleo Combustível e/ou Carvão como
fontes de energia para
seus processos. Dada a grande relevância destes
combustíveis em seus custos de
manufatura e seu caráter estratégico para a estabilidade
das operações, torna-se
extremamente pertinente a busca contínua por alternativas
mais econômicas, com
garantia de oferta no longo prazo e atendimento aos
requisitos ambientais cada
vez mais restritivos. Uma particularidade importante para
as duas plantas é a sua
localização em regiões brasileiras sem oferta de Gás
Natural (GN) canalizado.
Neste contexto, o Gás Natural Liquefeito (GNL) é a
alternativa logística estudada
neste trabalho para suprimento de GN para as plantas
estudadas. Ainda não
ocorrem no Brasil importações de GNL, entretanto a
primeira
descarga do
combustível deve ocorrer em breve e pode passar a ser
fonte
regular de energia
para diversos consumidores. Exatamente por ser tão
recente
enquanto alternativa
de suprimento de energia para o mercado brasileiro, busca-
se conhecer suas
características logísticas e, considerando o valor de
investimento necessário,
avaliar a viabilidade econômica de sua implementação.This dissertation presents two case studies of Industrial Plants that currently use Fuel Oil and/or Coal as source of energy for its processes. Given the great importance of these fuels in the manufacturing costs and its strategic role to the stability of the operations, it is extremely relevant the continuous search for most economic alternatives, with long term supply security and alignment with more and more restrict environmental standards. An important particularity of these two plants is its location in Brazilian areas without availability of Natural Gas (NG) in pipelines. Therefore, the Liquefied Natural Gas (LNG) is the logistic alternative to supply the NG to the plants under analysis. Still Brazil does not import LNG, however the first unloading of this fuel shall happen very soon and may become a regular source of energy to many consumers. Exactly for being such a recent energy supply alternative to the Brazilian market, it is so important to understand its logistic and, considering the value of needed investments, evaluate its economic viability of implementation.
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Whitmore, William D. "A Review of Energy and Environmental Policy for Offshore Liquefied Natural Gas (LNG) Terminals." ScholarWorks@UNO, 2006. http://scholarworks.uno.edu/td/401.
Full textAbstract:
The Maritime Transportation Security Act of 2002 amended the Deepwater Port Act of 1974 allowing energy industries to construct offshore liquefied natural gas (LNG) terminals. The industry friendly amendments weakened environmental regulations resulting in quick approval of several terminals that utilize environmentally damaging open-loop regasification systems. The objectives of this case study are to determine what influences national energy security and energy industries have in offshore LNG policy development and what energy policy tactics are utilized by the George W. Bush administration. Senate testimony, industry publications, federal legislation, and permit case studies reveal the prominence of concerns for national energy security and industry complaints over terminal siting and permitting process delays. An eco-Marxist argument is visible when the Bush Administration centralizes the policy process by working cooperatively with energy industry elites to promote energy development and attempts to limit the role of certain federal and state agencies and citizens.
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Bolen, Matthew Scott. "A new methodology for analyzing and predicting U.S. liquefied natural gas imports using neural networks." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2610.
Full textAbstract:
Liquefied Natural Gas (LNG) is becoming an increasing factor in the U.S. natural gas market. For 30 years LNG imports into the U.S. have remained fairly flat. There are currently 18 permit applications being filed in the U.S. and another 10 permit applications being filed in Canada and Mexico for LNG import terminals. The EIA (Energy Information Agency) estimates by 2025 that LNG will make up 21% of the total U.S. Natural Gas Supply.
This study developed a neural network approach to forecast LNG imports into the U.S. Various input variables were gathered, organized into groups based on similarity, and then a correlation matrix was generated to screen out redundant variables. Since a limited number of data points were available I used a restricted number of input variables. Based on this restriction, I grouped the input variables into four different scenarios and then generated a forecast for each scenario. These four different scenarios were the $/MMBTU model, natural gas energy consumption model, natural gas consumption model and the energy stack model.
The standard neural network approach was also used to screen the input variables. First, a correlation matrix determined which variables had a high correlation with the
output, U.S. LNG imports. The ten most correlated input variables were then put into correlation matrix to determine if there were any redundant variables. Due to the lack of data points only the five most highly correlated input variables were used in the neural network simulation.
A number of interesting results were obtained from this study. The energy stack model and the consumption of natural gas forecasted a non-linear trend in U.S. LNG imports, compared to the linear trend forecasted by the EIA. The energy stack model and consumption of natural gas model predicted that in 2025 U.S. LNG imports will be about 6.5 TCF, while the other three models prediction is about three times as less. The energy stack model is the most realistic model due its non-linear trend, when the rapid increase of LNG imports is going to occur, and the quantity of U.S. LNG imports predicted in 2025.
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Udechukwu, Izunna David. "Development of a model for computational fluid dynamics simulation of liquefied natural gas vapour dispersion." Thesis, Kingston University, 2015. http://eprints.kingston.ac.uk/34537/.
Full textAbstract:
Liquefied Natural Gas (LNG) is currently playing an important role in the world energy markets. This is evidenced by growing demand and increased construction of LNG facilities across Europe and the United States. In the event of spill from any of the facilities handling LNG such as during liquefaction, transportation or regasification, flammable vapour is formed which disperses through the atmosphere constituting fire and explosion hazards. To ensure public safety in the midst of growing LNG demand and facilities construction, industries are usually mandated to demonstrate that public safety will not be undermined by potential spill from their facilities. One method that is currently being used to demonstrate compliance is through LNG vapour dispersion modelling using Computational Fluid Dynamics (CFD). CFD modelling of dispersion phenomena is a challenging task that requires rigorous methodology to account for the underpinning physical processes. The modelling process comprises of two steps: source term quantification and vapour dispersion modelling. Source term quantification involves the physical description of spill rate, pool spreading and evaporation. Vapour dispersion utilizes the result of source term quantification in order to predict the turbulent entrainment and dilution process with the ambient wind. Existing models employ simplifying assumptions that circumvents explicit source term modelling. The spilled liquid is assumed to fill the entire substrate immediately at which time the spill rate becomes equal to evaporation rate. Following this assumption, a fixed inlet patch area and evaporation rate is applied at the gas inlet boundary. This approach fails to incorporate the transient pool development and subsequent evaporation into the dispersion modelling process. The primary aim of this dissertation is to develop an efficient integrated pool spreading, evaporation and dispersion (I-PSED) model code for LNG vapour dispersion simulation. This represents a significant shift from the traditional method since the new methodology combines the spilling process, spreading on substrate and transient evaporation into a unified model. For the spilling process, the well- known orifice model has been adopted to predict the spill rate taking into account the decreasing head. A mass balance approach is adopted in conjunction with a well¬established similarity model for spreading calculation. Heat transfer to the spreading pool is incorporated based on film boiling correlation. The spreading model was then coupled to an atmospheric dispersion model within OpenFOAM framework through the implementation of a new boundary condition in which the gas inlet patch area changes based on the instantaneous pool radius. The developed integrated code (I-PSED) is validated against data from the Coyote Series LNG Spill experiments as well as against Shell's Maplin Sand LNG spill experiments. Predictions of concentration obtained using the proposed model and those obtained using conventional approach are compared against experimental data at specific sensor locations. Also, arc-wise comparisons are carried out. Predicted results show good agreement with experimental data and clearly put the newly developed model ahead of the conventional approach for CFD simulation of LNG vapour dispersion. With the newly developed approach, the cloud arrival time and average concentrations at most sensor locations were better predicted. The effect of the turbulent production due to density stratification (buoyancy) created by the release of cryogen is investigated. Experience gathered shows that incorporation of a production term due to buoyancy in the turbulence model improves predictions under unstable atmospheric condition, otherwise the concentration field would be grossly over-predicted.
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ESTEVES, ALAN DA SILVA. "MATHEMATICAL MODELING OF CRYOGENIC SPILLS AND POOL FIRES IN THE LIQUEFIED NATURAL GAS (LNG) MARITIME TRANSPORTATION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2010. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=16726@1.
Full textAbstract:
PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROGás Natural Liquefeito (GNL) vem sendo transportado desde 1959 em navios metaneiros, elos essenciais na movimentação do GNL entre as locações de produção e consumo. Este trabalho apresenta modelagens para: (i) mecânica do derrame e espalhamento de fluido criogênico no mar, decorrente de punção no casco desses vasos, e (ii) subsequente incêndio de difusão turbulenta. A revisão bibliográfica contempou seis décadas, e não foram encontradas evidências de que os temas, espalhamento criogênico e incêndio da poça com difusão turbulenta, tivessem sido tratados em único trabalho. Essa lacuna foi identificada, e os assuntos foram acoplados de forma inédita e implementados em dois códigos computacionais. O derrame/espalhamento é modelado com formulação integral conservativa, tendo como parâmetros a área do rasgo, área máxima da poça derramada e tempos de descarga e vaporização do criogênico no mar. O escoamento foi modelado com rasgos de 1 a 100 m(2) coerentes com a indústria de GNL, formando poças semicirculares. A modelagem da pluma térmica contempla poças circulares entre 10 e 500 m de diâmetro, bem como zonas de combustão e intermitência da pluma térmica. Provê esquema consistente e robusto para o desenvolvimento de parâmetros adimensionalizados de escala, possibilitando correlacionar e extrapolar o comprimento da pluma visível, com a inclinação e o arrasto da mesma, com o poder emissivo de sua superfície e a vazão mássica de vaporização do combustível criogênico na poça. Avalia também: (i) a variação axial do poder emissivo com a altura da pluma visível, (ii) a queima do combustível ao longo da zona luminosa (base do incêndio), e (iii) o transporte de radiação térmica emitida por gases cinza e partículas de fuligem na zona de combustão, considerando a emissão e absorção nas regiões oticamente fina e espessa da pluma térmica.
Liquefied Natural Gas (LNG) has been carried since 1959 in methane carriers, which are the essential link in the movement of LNG between the locations of production and consumption. This thesis presents modeling to: (i) the fluid mechanics of spills/scattering at sea of a cryogenic fluid, due to puncture the hull of these vessels, and (ii) the subsequent burning of the pool by turbulent diffusion fire. The literature review contemplated six decades, and no evidence was found that the themes such as scattering of cryogenic pool followed by turbulent diffusion fires were treated in a single work. This gap was identified, and the subjects were connected in an unprecedented manner and implemented in two computer codes. The spill/scattering is modeled with conservative integral formulation, having as parameters the area of maximum pool poured on the sea and unloading and vaporization times of cryogenic. The flow was modeled with tears between 10 and 100 m(2), consistent with the LNG industry, forming semicircular pools. The modeling of the fire thermal plumes considers circular pools with diameters varying between 10 and 500 m, and combustion and intermittency zones of the thermal plume. Provides a consistent and robust scheme for the development of dimensionless scale parameters, allowing to correlate and extrapolate the length of the visible plume, with the its tilt and drag, its surface emissive power and with cryogenic fuel vaporization mass flow rate in the pool. It also evaluates: (i) the axial variation of emissive power with height of the visible plume, (ii) the burning of fuel along the luminous zone (the base of the fire), and (iii) the transport of thermal radiation emitted by gray gases and soot particles within the combustion zone, considering the emission and absorption in optically thin and thick regions of the thermal plume.
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Mody, Pritesh (Pritesh Chetan). "Impact of Liquefied Natural Gas usage and payload size on Hybrid Wing Body aircraft fuel efficiency." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62319.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2010.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 91-94).
This work assessed Hybrid Wing Body (HWB) aircraft in the context of Liquefied Natural Gas (LNG) fuel usage and payload/range scalability at three scales: H1 (B737), H2 (B787) and H3 (B777). The aircraft were optimized for reduced fuel burn and airframe noise at approach, based on NASA N+3 goals for the 2030 timeframe. Well-to-wake greenhouse gas emissions for LNG from conventional sources were estimated to be 16% lower than conventional Jet A. Minimally insulated in-wing storage was shown to reduce HWB wing loading and improve fuel burn by 7-12%. Improvements were based on 16% higher fuel specific energy, 17% lower skin friction drag through wall cooling on the wing bottom and 11-16% lower SFC through alternative cycles. Considerations were made for 1% insulation/fuel weight and 39% additional fuel volume but secondary systems and icing issues were not examined. Though technologically viable, significant developmental hurdles, infrastructure demands and safety risks would need to be overcome before these benefits could be achieved. The global optimization framework was presented using a hybrid genetic algorithm for simultaneous optimization of airframe/propulsion/operations. Due to cabin aisle height restrictions, unusable white" space for the H1 designs resulted in excessive empty weight fractions. However the design achieves 45% lower fuel burn than the B737-800 due to its all lifting configuration, advanced propulsion system and assumed structural advancements. The H2 and H3 designs mitigated this drawback by carrying increased payload in a larger, more efficiently packaged centerbody with H3 fuel burn being 52-56% lower than the B777-200LR. However as airport span constraints for the B777 class aircraft were reached, the scaling performance was observed to asymptote with lower improvement from H2 to H3, as compared from H1 to H2.
by Pritesh Mody.
S.M.
34
Larson, Parker E. (Parker Edward) 1979. "The technology and economic feasibility of offshore liquefied natural gas receiving terminals in the United States." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/91797.
Full textAbstract:
Thesis (S.M. in Ocean Systems Management)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 2003.Includes bibliographical references (p. 96-102).
by Parker E. Larson.
S.M.in Ocean Systems Management
35
Borkovec, Ondřej. "Zkapalněný zemní plyn." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-319687.
Full text
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Oluwole, Samson Abayomi. "Sustainable development challenges of contemporary technologies : Nigeria liquefied-natural-gas project as a case study / S.A. Oluwole." Thesis, North-West University, 2008. http://hdl.handle.net/10394/4120.
Full textAbstract:
The way people view development is changing. The world now advocates for a development that also considers future generations. There is a paradigm shift towards sustainable development - a development in today's lifestyle without destroying the resources for tomorrow generations. Sustainable development is a broad concept that addresses how human activities impact on the economic, environmental and social well-being of an ecosystem; however, practical application of the sustainability concept is complex because its objective assessment is elusive.
It is often said that the effect of technology on society has never been more profound than today. As mankind develops in science and technology to improve on his well-being, certain impacts are made on the systems that support human existence. Liquefied natural gas (LNG) technology, like gas-to-liquid (GTL) technology, is a latest innovation conceived to 'fight' the problem of gas flaring, and help contribute to the social and economic growth of the people; but it is necessary for man to know if these contemporary technologies are sustainable.
This dissertation critically appraises the impact of the LNG project on the community of Bonny Island in Nigeria from a holistic perspective. The approach to the research work is three-fold: an appropriate sustainability framework is selected based on certain criteria; sustainability indicators are developed from the chosen framework; and the sustainability indicators are used to assess the impact of the project on the flora and fauna of the community.
To have a clear picture of the impact of Nigeria LNG on its host community, Epe-Waterside is chosen as a control community because of its similar socio-geographical outlook to Bonny Island community. The control community is then subjected to the same set of sustainability indicators for a comparative analysis. The outcome of the research work shows that, though the economic and social conditions of Bonny Island seem much better, its environmental status remains a challenge. In other words, it can be concluded that the present approach to the operation of the LNG technology is not sustainable.Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2009.
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Yip, Arthur Hong Chun. "Modelling the global prospects and impacts of heavy duty liquefied natural gas vehicles in computable general equilibrium." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/95587.
Full textAbstract:
Thesis: S.M. in Technology and Policy, Massachusetts Institute of Technology, Engineering Systems Division, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 69-71).
Natural gas vehicles have the prospects of making substantial contributions to transportation needs. The adoption of natural gas vehicles could lead to impacts on energy and environmental systems. An analysis of the main factors and trends that affect adoption of natural gas vehicles such as vehicle costs, infrastructure costs, and fuel economics was performed. The fuel cost analysis showed that assuming production and distribution at scale, liquefied natural gas (LNG) can be competitive as a diesel fuel substitute for heavy duty vehicles in the US, and also in EU and China. A methodology of incorporating heavy duty natural gas vehicles into a computable general equilibrium (CGE) economic modelling was developed to investigate the potential adoption and impacts. Modelling variables such as vehicle and infrastructure costs were tested and several scenarios were applied to examine the general equilibrium impacts on natural gas vehicle adoption and the general equilibrium impacts of resulting natural gas vehicle adoption. Climate policy scenarios were also developed and tested. In the base case scenario, results showed significant adoption of LNG trucks (Class 8) in the US, with 10% penetration of heavy duty trucks by 2020 and up to 100% by 2040. In China and the EU, adoption was projected to be slower due to higher natural gas prices. In the US, introduction of LNG trucks resulted in moderately higher natural gas prices, slightly lower oil prices, and a small reduction in total GHG emissions, relative to scenarios without LNG truck availability. The development of natural gas fuelled transportation is still in its infancy and CGE modelling offers a tool that can be applied to test a wide range of assumptions of cost development and relative prices.
by Arthur Hong Chun Yip.
S.M. in Technology and Policy
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Godderidge, Bernhard. "A phenomenological rapid sloshing model for use as an operator guidance system on liquefied natural gas carriers." Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/142869/.
Full textAbstract:
A concept for a non-intrusive sloshing guidance system based on a phenomenological Rapid Sloshing Model is proposed to reduce the operational risk of sloshing damage to LNG carriers. A numerical sloshing model is implemented in a commercial Navier-Stokes Computational Fluid Dynamics (CFD) code which uses a volume-of- fluid approach for the simulation of multi- fuid problems. The effect of spatial and temporal discretisation and turbulence is investigated using systematic variation. Dimensional analysis of the multiphase flow regime and examination of the relative velocity at the fluid interface show that an inhomogeneous multiphase model is appropriate for the simulation of a violent sloshing flow. This is conrmed by the good agreement with the experimental data of Hinatsu. The effect of fluid compressibility is investigated for sloshing impacts and a criterion based on wave propagation is developed to assess the importance of compressibility. When modelling sloshing with large air bubble entrainment, the choice of fluid compressibility model is shown to have a significant influence on pressure magnitude and frequency of oscillation required for structural assessment and a thermal energy model is required. The Rapid Sloshing Model (RSM) is based on the observation that the centre of mass of a sloshing fluid tends to follow a particular trajectory. Using a phenomenological modelling approach, the forces affecting the sloshing response are approximated with mathematical functions for restoring force, damping and sloshing impacts. Calculation times for the resulting equations are typically 0.1% of real time on a desktop PC. A case study of sloshing induced by periodic rotation and translation of two-dimensional longitudinal and transverse sections of membrane LNG tanks is carried out using RSM. RSM is set up using one CFD simulation not considered in the case study and the RSM solutions are then compared to the independent CFD solutions. The fluid momentum from RSM is usually within 5%{15% of the CFD solution for excitation at and near the first resonant period at a filling level near the critical depth. An irregular surge motion profile from an ITTC two-parameter spectrum is applied to the tank and the mean error from the RSM solution remains below 15% when using momentum and transverse force. When applied to sloshing with a 10% filling level excited by an irregular seaway a mean error of 9.6% is obtained. Compared to existing phenomenological modelling approaches the RSM methodology reduces the error by an order of magnitude in sloshing scenarios of practical interest. A non-intrusive sloshing guidance system based on the Rapid Sloshing Model which is suitable for installation on existing and newbuild LNG carriers can be implemented by applying motion data measured onboard to the RSM to provide operator guidance on the sloshing severity in partially filled LNG tanks. The RSM is set up for a particular LNG carrier with existing sloshing data from the design and class approval stages.
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Chai, Jian. "Automated As-built Information Modelling for Construction Monitoring with Vision Data in Liquefied Natural Gas (LNG) Plants." Thesis, Curtin University, 2017. http://hdl.handle.net/20.500.11937/65984.
Full textAbstract:
This research aims to develop automated methods of retrieve as-built information from vision data in LNG plants and to use the developed methods to improve the productivity in the LNG industry. This research investigates class-level and further object-level interpretation of point cloud objects in LNG plants. By developing scaffolding detection methods, this research also contributes novel scaffolding construction monitoring methods using intrinsically safe cameras.
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Wang, Wen-Bohr. "Optimization of expander plants /." Access abstract and link to full text, 1985. http://0-wwwlib.umi.com.library.utulsa.edu/dissertations/fullcit/8520757.
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Andrade, Thalles Allan 1988. "Otimização de ciclos de refrigeração para a produção de gás natural liquefeito." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266096.
Full textAbstract:
Orientador: José Vicente Hallak d'AngeloDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
Made available in DSpace on 2018-08-25T15:12:16Z (GMT). No. of bitstreams: 1 Andrade_ThallesAllan_M.pdf: 2702197 bytes, checksum: 32c6cee79361c26e4489867146b0682e (MD5) Previous issue date: 2014
Resumo: Por se tratar de um combustível fóssil menos emissor de gás carbônico ao meio ambiente do que outros combustíveis, a demanda mundial de gás natural para sua utilização como fonte energética tem aumentado nos últimos anos. No entanto, quando a quantidade requerida de importação do gás natural é alta e é grande a distância entre os países fornecedores e compradores, o transporte do gás por meio de gasodutos torna-se inviável, acarretando na necessidade de produção de gás natural liquefeito. Ao se liquefazer a uma temperatura próxima a -160 °C, o volume do gás natural é reduzido em até 600 vezes, permitindo ser transportado a grandes distâncias por meio de embarcações especiais. Na liquefação do gás natural estão envolvidos ciclos de refrigeração que podem ser utilizados por diferentes rotas. Os principais tipos de ciclo de refrigeração são o ciclo de compressão de vapor e o ciclo de absorção. Nesse trabalho, foram simulados no programa Aspen HYSYS, versão 7.3, os ciclos cascata e APCI para a produção de GNL, que utilizam ciclos de refrigeração por compressão de vapor. O coeficiente de desempenho global do ciclo APCI alcançado com as simulações foi maior que o do ciclo cascata: 1,690 contra 0,839. Em seguida, um dos subciclos de compressão de vapor envolvidos no ciclo APCI foi substituído por um subciclo de absorção de efeito simples, utilizando-se diferentes combinações de pares refrigerante/absorvente (NH3/H2O, NH3/DMF, R22/DMF e R134a/DMF). O ciclo com o par NH3/DMF foi aquele com os melhores resultados para o coeficiente de desempenho. Finalmente, foram realizadas duas etapas de otimização dos ciclos propostos: uma delas através da maximização do COP dos ciclos de refrigeração e outra baseada na minimização dos custos dos processos, referentes aos custos dos principais equipamentos envolvidos. A maximização conseguiu atingir COP igual a 2,062 para o ciclo cascata e 2,505 para o ciclo APCI. Dentre os pares avaliados no ciclo APCI modificado, o par NH3/DMF manteve-se com o melhor COP do subciclo de absorção. Na minimização dos custos, obteve-se o custo dos equipamentos de US$ 4,1 milhões para o ciclo cascata e US$ 14,3 milhões para o ciclo APCI original. Em relação aos pares do ciclo APCI modificado, o par NH3/H2O apresentou os menores custos, tanto antes quanto depois da otimização, alcançando US$ 9,8 milhões
Abstract: Because it is a fossil fuel that emits less carbon dioxide to the environment than other fuels, worldwide demand for natural gas for use as energy source has increased in recent years. However, when the required amount of imports of natural gas is high and there is a great distance between suppliers and buyers of the gas, the gas transportation through pipelines it is not feasible, resulting in the need to produce liquefied natural gas (LNG). When the gas reaches a temperature close to -160 ° C, its volume is reduced by up to 600 times, allowing the liquefied natural gas to be transported over long distances through special ships. Liquefaction of natural gas involves refrigeration cycles that may be used by different routes. The main types of refrigeration cycle are the cycle vapor compression cycle and absorption cycle. In this study, it was simulated, on Aspen HYSYS, version 7.3, the cascade and the APCI cycles, to roduce LNG using vapor compression refrigeration cycles. The overall COP for the APCI cycle achieved after the simulations was greater than that the cascade cycle coefficient of performance: 1.690 against 0.839. Then, a vapor compression subcycle involved in the APCI cycle has been replaced by a single-effect absorption cycle, using different combinations of refrigerant/absorbent pairs (NH3/H2O, NH3/DMF, R22/DMF and R134a/DMF). The modified APCI cycle using the pair NH3/DMF was the one with the best results for the coefficient of performance. Finally, two stages of the proposed optimization cycles were performed: one through the maximization of the COP of the refrigeration cycles and one based on the minimization of process costs, regarding the costs of major equipment involved. Maximization has achieved COP equal to 2.062 for the cascade cycle and 2.505 for the APCI cycle. Among the pairs evaluated in the modified APCI cycle, the pair NH3/DMF remained with better COP of the absorption subcycle. In minimizing of costs, it was obtained the equipment cost of $ 4.1 million for cascade cycle and $ 14.3 million for the original APCI cycle. Regarding the modified APCI cycle, the pair NH3/H2O had showed the lowest cost, both before and after optimization, reaching $ 9.8 million
Mestrado
Engenharia Química
Mestre em Engenharia Química
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Nonekuone, Jolomi. "Model for marketing liquefied petroleum gas in Nigeria: Warri as a case study / Nonekuone Jolomi." Master's thesis, North-West University, 2008. http://hdl.handle.net/10394/4165.
Full textAbstract:
Despite the huge national energy resources, many Nigerians do not have access to high
quality, modern energy services. For those with access, energy supply lacks reliability,
especially in the case of liquefied petroleum gas (LPG). Hence this research considers the
possibility of enhancing the household use of LPG. It analyzes the factors affecting the
current demand and supply. Salient features of the LPG supply and distribution system
were also discussed.
On the basis of the existing situation, barriers of increasing LPG use, in particular, the
problems regarding affordability, priCing, government poliCies, safety, transportation and
distribution were analyzed and identified statistically using the chi-square statistical
method as a tool.
Finally, on the basis of the challenges identified, suggestions and recommendations were
made regarding the policies through which the problems could be overcome. Furthermore,
a model was developed and tested for an effective marketing strategy of LPG in Warri
Nigeria.
iiThesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
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Fossa, Alberto José. "Aspectos da conformidade no mercado de gás combustível e o impacto na sua expansão." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/86/86131/tde-25052012-171913/.
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Muito se têm noticiado sobre as possibilidades de expansão do uso do gás combustível como energético no âmbito comercial e residencial, porém entende-se que tal promessa deveria ser precedida de uma vasta e ampla discussão estratégica sobre os mecanismos necessários a serem desenvolvidos pelos agentes da sociedade para que tal expansão possa se concretizar. Dentro desse enfoque, entende-se como preocupante o desconhecimento a respeito das características de produtos e serviços utilizados, bem como o baixo grau de capacitação da indústria de prestação de serviços de instalações, andando de mãos dadas com a própria indústria da construção civil. Sem produtos ou serviços adequados é difícil prever a possibilidade concreta da expansão do gás no segmento residencial. Obviamente existem as abordagens sobre mudanças culturais a respeito da utilização do gás como energético, disponibilidade de aparelhos adequados para sua utilização, fatores econômicos envolvendo o preço do gás e uma centena de outros temas complementares. Todos esses tópicos podem ser considerados estratégicos. A dissertação pretende focar o problema da conformidade e da conseqüente disponibilização de produtos e serviços ao mercado. O trabalho explora as estratégias utilizadas para provocar melhoria e capacitação de segmentos de mercado, atrelando-os à resultados de competência e competitividade, através de monitoramento da sua conformidade com requisitos de produtos e serviços previamente estabelecidos. Discorre-se sobre as estratégias passíveis de serem utilizadas para fomento do desenvolvimento deste segmento de mercado e aborda-se os modelos válidos de avaliação de conformidade existentes atualmente no Brasil, discutindo propostas para o caso específico do monitoramento da infra-estrutura de distribuição de gás combustível no país. Utilizando-se, então, de um arcabouço de estruturas teóricas, apresenta-se um caso real do ponto de vista do mercado consumidor, particularizando a atuação da Comgás no Estado de São Paulo, discorrendo sobre as preocupações da empresa com relação à conformidade no mercado e estabelecendo paralelos entre tais iniciativas, as premissas teóricas e lacunas existentes no processo. O trabalho levanta o histórico técnico sobre modelos de avaliação de conformidade, apresentando um exercício de reflexão a respeito de propostas a serem potencialmente adotadas pelo segmento de mercado no caso de construção da infra-estrutura para condução e distribuição de gás combustível aos consumidores finais.It has been noticed about the possibilities of gas uses expansion in commercial and residential scope, however it understands that such promise would have to be preceded of a great strategic discussion concerning the necessary ways to be developed for the society agents so that such expansion can be materialize. Looking for this approach, its worry about the unfamiliarity regarding the products and services characteristics, as well as the low degree of services installations industry qualification, walking together with the building construction industry. Without adequate products or services it is difficult to foresee the concrete possibility of the gas expansion in the residential segment. Obviously its necessary to consider the aspects on cultural changes regarding the gas uses, availability of gas appliances, economic factors involving the gas price and a hundred of other complementary subjects. All these topics can be considered like strategic. The paper intends to focus the problem of the conformity and the consequent availability of products and service to the market. The work explores the strategies used to improve qualification of market segments, connecting them with the results of ability and competitiveness, through inspection of its conformity with requirements of products and services previously established. It is discoursed on the strategies to be used for promotion this market segment development and currently approaches the valid conformity evaluation models existing of conformity in Brazil, arguing proposals for the specific case of the combustible gas distribution infrastructure inspection in the country. Using the theoretical structures, it presents a real case of the consuming market point of view, distinguishing the performance of the Comgás in the São Paulo State, discoursing on the concerns of the company with regard to conformity in the market and establishing parallel between such initiatives, the theoretical premises and existing gaps in the process. The paper raises the description technician on conformity models evaluation, presenting an exercise of reflection regarding proposals to be potentially adopted for the market segment in case of infrastructure construction for gas conduction and distribution to the end consumers.
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Sousa, Francisco Jose Rocha de. "A geração termeletrica : a contribuição das termicas a gas natural liquefeito." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264491.
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Orientador: Sergio Valdir BajayDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-14T02:09:38Z (GMT). No. of bitstreams: 1 Sousa_FranciscoJoseRochade_M.pdf: 2082998 bytes, checksum: 6b17535d59d9d8fe0bb7be02166c05d0 (MD5) Previous issue date: 2009
Resumo: O objetivo desta dissertação é ampliar a compreensão da geração termelétrica, em particular das termelétricas a gás natural, e da relação entre os setores elétrico e de gás natural no Brasil. Especial atenção é conferida aos leilões públicos de energia, particularmente aqueles na modalidade disponibilidade de energia, opção que tem permitido a contratação de empreendimentos termelétricos a combustíveis fósseis. O trabalho faz avaliação da atratividade do investimento em térmica a Gás Natural Liquefeito - GNL já contratada em leilões públicos. Traz, também, estimativa da competitividade de termelétricas, com ênfase para as termelétricas a GNL. Verificou-se que a capacidade instalada das termelétricas a gás natural deverá ser significativamente ampliada até 2017, o que reforçará o vínculo entre os setores elétrico e de gás natural. Foi constatado que o custo de geração em uma termelétrica a gás natural é fortemente influenciado pelo período de tempo durante o qual ela permanece em operação e pelo preço do gás natural. Adicionalmente, constatou-se que o investimento na construção das termelétricas a GNL contratadas na modalidade disponibilidade de energia mostra-se bastante atrativo
Abstract: The objective of this thesis is to improve the understanding of thermal power, in particular natural-gas-fired power plants, and the relationship between the power sector and the natural gas sector in Brazil. Close attention is paid to the public auctions to hire energy, especially the ones aimed at hiring capacity, option which has allowed the hiring of fossil-fuel power plants. The thesis gives an idea of the attractiveness of the investment in a Liquefied Natural Gas - LNG powered plant hired in a public auction. It also presents an assessment of the competitiveness of thermal plants, with emphasis to the LNG-fired power plants. It was learnt that the natural-gasfired power plant capacity will increase significantly until 2017, which will reinforce the bond between the power sector and the natural gas sector. Another important finding is that the generation cost of a natural-gas-fired power plant is strongly influenced by the length of time it operates and by the natural gas price. Furthermore, the study shows that the investment in the construction of a LNG powered plant hired in a public auction is very attractive
Mestrado
Planejamento de Sistemas Energeticos
Mestre em Planejamento de Sistemas Energéticos
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Stradioto, Diogo Ângelo. "Análise energética e exergética da cadeia do gás natural líquido e a integração do processo de regaseificação com ciclos combinados de potência." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/32024.
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Este trabalho estuda a cadeia do Gás Natural Líquido (GNL) e propõe utilizações para a recuperação da energia do processo de regaseificação em ciclos de potência acoplados. Primeiramente, aborda a cadeia de abastecimento do GNL, identificando e quantificando os pontos consumidores de energia, destruidores de exergia e a reevaporação de massa ocorrida quando o metano esta na fase líquida. Posteriormente, avaliam-se as possibilidades do aproveitamento energético do processo de regaseificação, que ocorre no final dessa cadeia. Trata-se da busca por ciclos térmicos mais eficientes e aumentar o aproveitamento do trabalho reversível dos sistemas, abordando três alternativas de plantas de potência para operarem acopladas ao fornecimento de GNL, com benefício mútuo para ambos os processos: promoção da regaseificação do GNL sem energia auxiliar e aumento da eficiência da planta de potência. O ciclo selecionado para a integração entre as plantas foi o (CHP) Brayton-Rankine com três formas diferentes de acoplamento. Os resultados obtidos mostram que 14,81% da energia contida no combustível na entrada da planta de liquefação é perdida ou consumida nos processos que envolvem a cadeia. Quando essa cadeia é acoplada a um ciclo de potência, obteve-se uma recuperação da energia gasta no processo de regaseificação que reduz a perda de energia para 12,65%. Pelo lado da planta de potência, a eficiência energética de um ciclo combinado operando sem estar acoplado à regaseificação do GNL é de 49,68%, com destruição de exergia de 1078,0 kJ/kg. Dependendo do tipo de acoplamento proposto, o rendimento subiu para até 61,53%, com conseqüente redução de destruição de exergia.This work studies the chain of Liquefied Natural Gas (LNG) and suggests its use for recovery energy in the process of regasification connected with cycles of power. First, it approaches the chain of supply chain of the LNG, identifies and quantifies the energy demand points, destruction of exergy and the reevaporation of mass occurred when the methane is liquid phase. After, the possibilities of the energy recovery of the regasification process are evaluated, that occurs in the end of this chain. The work searches for more efficient thermal cycles and the increase the recovery of the reversible work of the systems. Three alternatives are evaluated of power plants to operate connected to the LNG regasification, with mutual benefit for both the processes: promotion of the regasification of the LNG without energy auxiliary and increase the efficiency of the power plant. The cycle selected for the integration between the plants was (CHP) Brayton-Rankine with three different forms of coupling. The results show that 14.81% of the energy contained in the fuel in the entrance of the liquefaction plant are lost or consumed in the processes that involve the chain. When this chain is connected to a power cycle, the recovery of the energy spent in the regasification process reduces the loss of energy for 12,65%. For the side of the power plant, the energy efficiency of the combined cycle operating without connected to the regasification of the LNG is 49,68%, with destruction of exergy of 1078,0 kJ/kg. Depending on the type of considered coupling, the energy efficiency is 61,53%, with consequent reduction of destruction exergy.
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Grimaldi, Federica. "La fisica della Transizione Rapida di Fase di Gas Naturale Liquefatto." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
Find full textAbstract:
La valutazione e il controllo dei rischi associati alla produzione, allo stoccaggio e al trasporto di Gas Naturale Liquefatto (o LNG, da Liquefied Natural Gas) è di fondamentale importanza per garantire la sostenibilità di questa attività. Gli scenari incidentali potenzialmente associati al rilascio accidentale di Gas Naturale Liquefatto durante il trasporto via mare sono la formazione di una nube infiammabile che può dar luogo ad una rapida combustione (Flash Fire), un incendio di pozza (Pool Fire) e la Transizione Rapida di Fase (Rapid Phase Transition).
L’RPT è il fenomeno meno probabile tra quelli precedentemente esposti, infatti le modalità con cui il fenomeno delle RPT può svilupparsi sono numerose e le condizioni che permettono un'effettiva evaporazione esplosiva non sono ancora chiare.
Valutare il rischio legato alla RPT di LNG su acqua risulta particolarmente complesso poiché il fenomeno dipende da numerosi variabili difficili da riprodurre sperimentalmente in modo coerente.Inoltre, a causa della complessità di alcune delle fasi del fenomeno, non è ancora stata elaborata una descrizione dettagliata e un modello matematico completo.
Lo scopo di questa tesi è stato quello di sviluppare uno strumento di previsione semplice ed affidabile, capace di simulare gli effetti di una RPT di LNG su acqua. Ciò è stato fatto avvalendosi della modellazione CFD grazie alla quale è stata simulata l’evaporazione di una pozza di LNG e la successiva diffusione in atmosfera. A tale scopo si è utilizzato il software open source OpenFOAM.
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Lindberg, Marcus, Per Johansson, and Mikael Joélius. "LNG - Framtidens fartygsbränsle : Vad är det som hämmar utvecklingen av LNG-drift i Sverige?" Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-39743.
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Sjöfarten står idag inför allt strängare miljökrav. För att uppnå miljövänligare resultat har allt fler rederier börjat se sig om efter ett miljövänligare bränsle. Östersjön är ett stort handelsområde där striktare krav från SECA träder i kraft den 1 januari 2015. Fartyg med LNG-drift diskuteras flitigt som ett alternativt bränsle inom den svenska sjöfartsnärningen, då utsläppen av NOx, svavel och partiklar är mindre än tjockoljan (HFO). Ett av problemen med LNG i Sverige är att det i dagsläget inte finns ett tillräckligt utvecklat infrastrukturnät för flytande naturgas. I denna rapport har vi med hjälp av kvalitativa intervjuer kartlagt svenska aktörer inom LNGs infrastrukturutveckling och vad det är som hämmar utvecklingen. Vår analys av intervjuerna visade att utvecklingen bromsades av att ingen vågat ta första steget. Hamnarna vill inte bygga terminaler om det inte finns en marknad för distribution och rederierna vill inte bygga fartyg om det inte finns tillgänglighet av LNG. Det har också framkommit att intresset från den svenska staten har varit mycket svagt, näst intill obefintligt. Det finns även en del tomrum i de svenska regelverken kring hanteringen av LNG, vilket är en av faktorerna till att LNGs utveckling hämmas.Shipping today faces stricter environmental requirements for pollution from vessels. Shipping companies have started to look for alternative fuel to achieve better environmental outcome. The Baltic Sea today is a major trading area for shipping . On 1 of January 2015 a new set of brand new and stricter regulation is getting implemented and these regulations are called SECA. Vessel running on LNG as an alternative fuel is today discussed extensively within the Swedish Maritime forum where emissions of NOx, sulfur and particles are less recipients than in heavy fuel oil (HFO). One of todays problems with a LNG distribution in Sweden are that the infrastructure is incomplete and outdated. This report has been built upon qualitative interviews with important actors within the Swedish maritime forum and also what impedes the development of the LNG’s infrastructure. The outcome of the interviews showed that the development has been slowed down because none within the Swedish martime forum have dared to take the first step. The ports does not want to develop terminals when there is no market demand and the shipping companies does not want to build vessel that runs on LNG when there is no market for distribution. Swedish governments involvement has been very weak, almost non-existing. There are also gaps in the Swedish regulations and restrictions of LNG cargo handling. This is aslo one of the factors that the development of LNG has been impeded.
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Suardin, Jaffee Arizon. "The application of expansion foam on liquefied natural gas (LNG) to suppress LNG vapor and LNG pool fire thermal radiation." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2906.
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Yun, Sangkook. "Experimental and thermodynamical studies of the phase equilibria for carbon dioxide in liquefied natural gas components at 77-219 K." Thesis, University of Southampton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328278.
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Wang, Peng. "Developing a Virtual Reality- and Lean-based Training Platform for Productivity Improvement of Scaffolding Installation in Liquefied Natural Gas Industry." Thesis, Curtin University, 2020. http://hdl.handle.net/20.500.11937/82406.
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This thesis aims to integrate lean and work postures to simultaneously improve productivity and health and safety and develop a lean- and virtual reality-based platform for effective education and training in scaffolding installation in turnaround maintenance projects. It represents an effort to help on-site workers in the Liquefied Natural Gas industry identify waste activities and achieve a balanced improvement in both productivity and health and safety through improved training in a virtual platform.