Natural Gas Technology

The purpose of the following project was to conduct a feasibility study and an analysis on the impacts of the implementa�on of biomethane into the University of Illinois at Urbana-Champaign bus system. The university is currently aiming to have net zero energy by 2050. The MTD bus transit is one of the most widely used transporta�on op�ons on campus. While it can be argued that transit systems emit less carbon than transporta�on such as cars, the buses s�ll contribute to the university's emissions. For every one gallon of diesel burned, approximately 22 pounds of carbon is emi�ed. However, these buses could poten�ally be powered by another source of fuel such as biomethane. This biomethane can be obtained from the food waste produced by the dining halls. The university currently has four and is installing the fi�h Grind2Energy system that can break up the waste. It can then be transported to Urbana-Champaign Sanita�on District Team 14 CEE190 Assignment M3 12/11/2021

No Ribeirão Coroa de Frade, na divisa entre os municípios de Terra Rica e Paranavaí, estado do Paraná, em 1966, foi construída uma central geradora hidrelétrica (CGH) conhecida como Usina Hidrelétrica Padre Eduardo, que tinha como objetivo fornecer energia elétrica à cidade de Terra Rica. A usina continuou em operação até 2015, quando, devido ao grande volume de chuvas, seu reservatório se rompeu e, desde então, encontra-se desativada. Dessa forma, este trabalho teve como objetivo estimar o potencial hidrelétrico dessa central hidrelétrica e definir as principais características da turbina hidráulica e do gerador elétrico a serem adquiridos caso a CGH Padre Eduardo seja reativada. Para isso, inicialmente, foi realizada uma pesquisa bibliográfica sobre geração hidrelétrica e sobre metodologias de dimensionamento de componentes de uma central hidrelétrica. Em seguida, através de relatos de funcionários do SAMAE (empresa proprietária da CGH) e de visitas ao local, foi realizado um levantamento da atual situação dos equipamentos e das instalações da usina. Devido à falta de dados sobre a vazão do curso d’água e da altura da queda, foram também realizadas estimativas para os valores dessas duas grandezas. A partir dos dados obtidos, então, foi estimada a potência elétrica a ser gerada pela CGH e foram definidas as principais características da turbina e do gerador. Assim, como resultado, obteve-se a potência estimada de aproximadamente 200 kW. Para a turbina, obteve-se que o tipo mais adequado é o Francis com caixa espiral, devendo trabalhar, preferencialmente, com uma velocidade síncrona de 600 ou 720 RPM. Além disso, caso o gerador seja acoplado diretamente à turbina (mesma velocidade síncrona), os resultados indicam que ele deverá ter 12 ou 10 polos, respectivamente, devendo trabalhar, preferencialmente, com tensões de 220/380 ou 480 V.

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In Coroa de Frade River, between the municipalities of Terra Rica and Paranavaí, state of Paraná, Brazil, in 1966, a mini hydropower plant known as Usina Hidrelétrica Padre Eduardo was built, which aimed to supply electricity to the city of Terra Rica. The plant continued to operate until 2015, when, due to heavy rainfall, its reservoir ruptured and has been deactivated since then. Thus, this work aimed to estimate the hydroelectric potential of this mini hydropower plant and define the main characteristics of the hydraulic turbine and the electric generator to be acquired if Usina Padre Eduardo is reactivated. For this, initially, a bibliographical research was carried out on hydroelectric generation and on methodologies for sizing components of a hydroelectric power plant. Then, through reports from SAMAE employees (company that owns Usina Padre Eduardo) and visits to the site, a survey was carried out of the current situation of the plant's equipment and facilities. Due to the lack of data on the flow of its watercourse and the height of fall (head), some estimates were also made for the values of these two magnitudes. From the data obtained, then, the electrical power to be generated by the mini hydropower plant was estimated and the main characteristics of turbine and generator were defined. Thus, as a result, an estimated power of approximately 200 kW was obtained. For the turbine, it was found that the most suitable type is the Francis with spiral casing, which should preferably work with a synchronous speed of 600 or 720 RPM. Furthermore, if the generator is coupled directly to the turbine (same synchronous speed), the results indicate that it should have 12 or 10 poles, respectively, and should preferably work with voltages of 220/380 or 480 V.

This article illustrates the criteria and methods applied for implementing a Geo-Tourist map of the Natural Reserve of "Salse di Nirano". This map is an "original" cartographic elaboration in the field of Italian thematic mapping. The "Salse" are small mud volcanoes genetically linked to the ascent to the surface of salty and muddy waters mixed with gaseous (methane) and, to a lesser extent, fluid hydrocarbons along tectonic discontinuities produced by overthrusting along the front of the Apennine chain. The mud volcanoes of the Modena Apennines have been known since a long time and have always aroused great interest: they are described in many papers, starting as early as Pliny the Elder, in around 50 A.D. Since the "Salse di Nirano" are one of the best developed mud-volcano phenomena of the entire Italian territory and among the largest in Europe, in 1982 a Natural Reserve was established in the area by the Emilia-Romagna Region; the reserve territory covers a total area of about 200 ha with elevations ranging from 140 to 308 m. By means of ArcView GIS computer program a Digital Terrain Model (DTM), a Geomorphologic map and a Geo-Tourist map have been elaborated and will be displayed at the Visitor Center of the Reserve. The orographic arrangement of the territory is effectively illustrated by DTM, which was implemented on the basis of altimetric data of the Regional Technical Map (CTR) of the Emilia-Romagna Region. The detailed geomorphologic features are represented in a Geomorphologic map, elaborated on the basis of bibliographic research, interpretation of aerial photographs and field survey. In the study area, where silty-clay soil types (Plio-Pleistocene in age) crop out, landforms and deposits resulting from the endogenetic activity of the mud volcanoes, running water, gravity, anthropogenic activities and polygenetic landforms were recognized. The Geo-Tourist map was derived (with appropriate simplifications and integration) from the Geomorphologic map. The Geo-Tourist map combines the most evident geomorphologic features (mud volcanoes, badlands, landslides, anthropogenetic landforms, bedrock, surface deposits, ponds, marshes etc.)-which can be observed and recognized even by non-experts-with fundamental tourist information (main roads, parking places, visitor center, excursion trails, picnic areas, panoramic points, restaurants and places to stay). The Geo-Tourist map and DTM are the characterizing documents of a new tourist map of the Reserve (Tourist-Environmental map). In particular, the Geo-Tourist map is a foldable, pocket-size, front/rear printed map, with explanatory notes in Italian and English: it was published with the financial support of the Municipality of Fiorano Modenese. This article proves that geomorphologic research can effectively contribute to the implementation of documents and maps useful in the field of tourism.

The design, installation, commissioning and operation of a fogging system for a large 655 MW combined cycle power plant is described. Technical details and practical installation issues are discussed. Special considerations as to how the fogging system could help in the augmentation of power during high temperature and low frequency operation of the gas turbine is discussed. Finally a discussion is made regarding the importance of inlet filtration and the proper selection of blade coatings.

Nowadays, the market for natural gas production and its use as a source of energy supply has been growing substantially in Brazil. However, the use of tools that assist the industry in the management of production can be essential for the strategic decision-making process. In this intuit, this work aims to evaluate the formulation of Holt Winter's additive and multiplicative time series to forecast Brazilian natural gas production. A comparison between the models and their forecast play a vital role for policymakers in the strategic plan, and the models estimated production values ​​for the year 2018 based on the information contained in the interval between 2010 and 2017. Therefore, It was verified that the multiplicative method had a good performance so that we can conclude this formulation is ideal for such an application since all the predicted results by this model showed greater accuracy within the 95% confidence interval.

From manufacturer Cryostar it's pamphlet on turbo-expander:

Cryostar designs all their turbo-expander packages to the strictest of industry standards and client requirements.

Complienace to API 617 is standard and in addition, each machine can be fully customised to meet even the most stringent of client requirements.

To assure customers on-time delivery to the agreed specification level, an engineering team is selected at the beginning of each project.

The team includes aero-designers, specialist in rotating machinery, instrumentation and control systems, seal gas and lube oil systems all coordinated by a project manager in conjunction with the quality department, fully involved at each step of the project.

O simulador interativo para treinamento de operadores e mantenedores é uma ferramenta desenvolvida com uma tecnologia de treinamento dinâmico do funcionamento, das contingências e dos defeitos de usinas termelétricas de ciclo combinado, emulando o tempo real. Implementado no Sistema de Gerenciamento de Informações de Processo PI System da OSISoft, software já utilizado por toda a ENDESA em suas usinas, sendo a simulação é realizada a partir da base os dados históricos da empresa. PALAVRAS-CHAVE ENDESA, OSISoft, simulador interativo, treinamento de operadores, usinas termelétricas de ciclo combinado 1.0 INTRODUÇÃO As usinas termelétricas de ciclo combinado são sistemas com alta eficiência térmica que possuem associadas à mesma planta, turbinas a gás e a vapor gerando energia elétrica.

hoje um museu, ela e outras pequenas geradoras formam o complexo de Marmelos ainda em operação (Marmelos 2), na categoria definida pela legislação atual como "Pequenas Centrais Hidrelétricas" (PCHs). Este modelo de aproveitamento hidrelétrico tem sido defendido por vários argumentos, dentre os quais, ser potencialmente menos agressivo ao ambiente e ter custo reduzido; é considerado um investimento de pequena monta. A questão da sustentabilidade econômica e ambiental de tais empreendimentos, à luz dos estudos de caso sobre esta experiência pioneira, foi o objeto de nossas reflexões. Os autores são membros de uma equipe multidisciplinar (historiadores

Good estimation of gas compressibility factor (z-factor) of gas is an essential key in numerous gas and oil calculations. In absence of data, the iterative methods were used to estimate z-factor. However, the accuracy of these correlations has become insufficient for estimating z-factor. Therefore, the objective of this study is to test the capability of various Fuzzy Logic (FL) model to predict z-factor in more accurate and precise. The FL model has three types: Fuzzy c-means (FCM), grid partition (GP), and sub-clustering (SC) Algorithms. These proposed FL models were compared with iterative methods to determine the best approach with the higher performance and reliability to predict z-factor. Around 6500 published and unpublished data points with a wide range of z-factor and reduced temperature and pressure were collected from several oil fields in the Middle East. The results display that the developed FL with various cluster techniques is more precise and trust than iterative methods and can be used in wide range of pseudoreduced pressure and temperature. The obtained results show that the FL with sub-cluster technique performs well with lower average relative percent error of 0.13% and higher accuracy (R2=1) than the others models.

Resumen El gas natural licuado (GNL), gas natural en fase líquida a una temperatura de-161°C y presión atmosférica, es la forma más rentable de transportar este combustible, cuando se tie-nen distancias superiores a los 3.800 km desde la fuente hasta los mercados de consumo debi-do a la reducción de su volumen (600 veces). La producción de GNL es una tecnología madura, con más de 30 años de experiencia, respaldada mundialmente por diferentes procesos comer-ciales. Este trabajo se basó en el estudio de las tecnologías de licuefacción existentes para aplicarlos al proyecto de nuestro país, teniendo en cuenta los procesos comercialmente dispo-nibles que se encuentran en la industria de GNL: proceso con intercambiadores de tubos en espiral, de cascada optimizada, el triple ciclo, entre otros. Se realizó un análisis comparativo de variables técnicas y económicas de tres tecnologías seleccionadas, tales como: flexibilidad, eficiencia, grado de madurez, aspectos ambientales, costo de capit...

This article presents the results of a numerical experiment and an analysis of temperature fields (coolers for gas) using cooling elements in the case study gas pipeline. An analysis of the temperature fields demonstrated several principles for the formation of a temperature field, which indicates the need to maintain a relative temperature for gas pumping. The essence of the experiment was to install an unlimited number of cooling elements on the gas pipeline. The purpose of this study was to determine at what distance it is possible to install cooling elements for the optimal gas pumping regime, regarding the synthesis of the control law and the determination of the optimal location and assessment of control error depending on the location of the cooling elements. The developed technique allows for the evaluation of the developed control system's regulation error.

The problem emerging in the natural gas plant is carbon dioxide content in the pipeline. Wellhead natural gas can contain as much as 30% carbon dioxide. Meanwhile, the minimum specification required includes no more than 2%-3% carbon dioxide. The separation of CO2 from biogas is indispensable to improve so that its quality can be improved. One of the separation methods is adsorption. The adsorption process was varied at the pressure

It is well known that carbon dioxide is one of the major pollutant agents to our environment, and its emission must be limited. Power plants mostly burn fossil fuel to generate electricity and hence produce a tremendous amount of pollutants such as CO2. In this work, a simple gas-turbine cycle is connected with a steam cycle unit to form a combined gas-steam power unit and hence, improves its thermal performance. Since testing at large scale is so costly, it is likely to use process simulation software to evaluate such processes. Post-combustion removal is one possible way to lower CO2 emissions from industrial plants, including power stations. Instead of discharging CO2 which is contented in the exhaust gas to the atmosphere, the carbon dioxide can be seized, transported and stored securely in a number of places, including geological formations, and depleted oil and gas reservoirs. The most favorable method for CO2 removal is by absorption in an amine-based solvent followed by desorption. The simplest and most used amine for CO2 removal is MEA (Mono-Ethanol Amine). The net power output of the selected simple-gas turbine unit for the analysis is 287.4 MW with thermal efficiency of 28.98%. Modeling and simulating this power unit indicates 40.7851 kg/s of CO2 is
emitted to the atmosphere. The aim of this work is to reduce this amount and contribute to the clean environment issues. According to this study, the rate of the emitted CO2 is reduced to 0.3888 kg/s, and to 0.4085 kg/s, when CO2 removal cycle is connected to the simple gas turbine cycle and to the combined gas-steam cycle, respectively.

A typical natural gas dehydration plant, which employs triethylene glycol (TEG) as the dehydrating agent, is simulated using a steady state flowsheeting simulator (Aspen Plus). All major units were included in the flowsheet, that is: absorption column, flash unit, heat exchangers, regenerator, stripper, and reboiler. The base case operating conditions are taken to resemble field data from one of the existing dehydration units operating in the United Arab Emirates (UAE). To explore effects of the thermodynamic model employed in the simulator on the reliability of the whole simulation process, different predictive mixing rules applied to two cubic equations of state (EOS), as programmed by the simulator, have been investigated. The EOS used in the simulation is the Redlich-Kwong-Soave (RKS) and the Peng-Robinson (PR), both with Boston-Mathias (BM) alpha function. In addition to the classical empirical mixing rules, the following ones are investigated: Predictive Soave-Redlich-Kwong-Gmehling (PRKS), Wong-Sandler (WS), and Modified-Huron-Vidal (MHV2) mixing rules. These mixing rules are all predictive in nature. The plant performance criteria that have been studied for their response to changes in the solvent circulation rate include: BTEX (benzene, toluene, ethyl benzene, and xylenes) emissions rate, desiccant losses (makeup), water content in the dehumidified natural gas, purity of the regenerated TEG, and reboiler heat duty. Comparison with the field data is done. Very diverse results have been obtained from the different models and mixing rules. No one single model gives the best results for all criteria.

Fouling is the deposition of undesired material on a heat transfer surface. It significantly decreases the thermal performance of heat exchangers. In this study, a novel method is proposed to monitor fouling in a thermosiphon reboiler. The method combines a physical model and a data-driven model to estimate the heat transfer mechanism. The overall heat transfer coefficient and heat flux are modeled by using physical models. Partial least square regression is used to model the tube-side film heat transfer coefficient. Additionally, a methodology to estimate fouling resistance is presented. The proposed method is demonstrated on a reboiler in a simulated debutanizer column.

Se presenta el trabajo llevado a cabo en una empresa fabricante de micro-circuitos para teléfonos celulares, en el cual se aplicó la metrología para el aseguramiento de los sistemas de medición y ahora se están utilizando estos para la optimización de los procesos productivos. En cuanto al aseguramiento metrológico se trabajó con la metodología MESURA en variables electromagnéticas y en cuanto a la optimización de los procesos se están implementando métodos de control estadístico de procesos. Dado que cada componente que se fabrica en la planta tiene múltiples características de calidad, y que la optimización de una de ellas puede influir o influye en el desempeño de las otras, se está en la fase de implementar un control estadístico de procesos multivariado. El artículo presenta los avances del proyecto en general, el estado actual del mismo y plantea el trabajo a futuro.

El objetivo del presente estudio es utilizar la simulacion numerica de Monte Carlo (SMC) para calcular la incertidumbre en la determinacion de aflatoxina B1 (mensurando y) en una muestra de mani de exportacion por Cromatografia Liquida de Alto Desempeno con Detector de Fluorescencia (HPLC-FD). El calculo se baso en la generacion de 5000 valores aleatorios para cada una de las 19 variables que influyen en el mensurando y, se introducen en la funcion que relaciona las variables y se obtienen 5000 valores aleatorios de la funcion. La incertidumbre se calculo como desviacion estandar poblacional. El programa se elaboro en lenguaje Maple y en hoja de calculo Excel, obteniendose los mismos valores de incertidumbre, 0.225543 y 0.225180. Estos resultados fueron comparados con los obtenidos por la aplicacion de la ley de propagacion de la incertidumbre y no hubo diferencias significativas. El contenido de aflatoxina B1 en la muestra de mani para exportacion con su incertidumbre expandida fue...

At the Aquistore Carbon Capture and Storage site, 13 C isotopes were analysed from mud gas samples collected during the drilling of the 3400 m deep injection and observation wells. From these results a compound specific isotope vertical depth profile was generated of the background carbon isotopes at that site. 13 C for methane ranged from-68‰ PDB near the surface to-39‰ at 3232 m depth. To date, this is the deepest isotope record in the Saskatchewan portion of the Williston Basin, from the deepest well(s) in the province of Saskatchewan.

Natural gas dehydration is an important process in the gas processing. In this process, water vapor is removed from natural gas streams since it can cause some problems in the next process. Application of structured packing in separation processes like natural gas dehydration has been increased since last few years. In this work, a domestic natural gas dehydration unit using triethylene glycol (TEG) was simulated. Predictive Redlich-Kwong-Soave (PSRK) equation of state was applied in the simulation. The existing tray column was replaced by structured packing and then was optimized. The results show that by replacing tray column with packed bed column can reduce the size of the column and also reduce the total annual cost (TAC) of the natural gas dehydration unit.

Good estimation of gas compressibility factor (z-factor) of gas is an essential key in numerous gas and oil calculations. In absence of data, the iterative methods were used to estimate z-factor. However, the accuracy of these correlations has become insufficient for estimating z-factor. Therefore, the objective of this study is to test the capability of various Fuzzy Logic (FL) model to predict z-factor in more accurate and precise. The FL model has three types: Fuzzy c-means (FCM), grid partition (GP), and sub-clustering (SC) Algorithms. These proposed FL models were compared with iterative methods to determine the best approach with the higher performance and reliability to predict z-factor. Around 6500 published and unpublished data points with a wide range of z-factor and reduced temperature and pressure were collected from several oil fields in the Middle East. The results display that the developed FL with various cluster techniques is more precise and trust than iterative methods and can be used in wide range of pseudoreduced pressure and temperature. The obtained results show that the FL with sub-cluster technique performs well with lower average relative percent error of 0.13% and higher accuracy (R2=1) than the others models.

There is new trend in the value of oil and gas in the world, with the value of Liquefied Petroleum Gas (LPG) soaring higher. It is due to its uses as a potential fuel in the several parts of the world, its demand in the petrochemical industries for plastics and automotive composites productions, and other uses. These results in steadily increases in price. There is also increase in volume of feed gas, which demands efficient LPG processing and recovery technology. This paper mainly focuses on comparative economic investigation options for Liquefied Petroleum Gas plant, which processes feed from natural gas wells and dehydrating units to produce Liquefied Petroleum Gas along with natural gasoline having a higher value as separate product. Recovery of LPG is possible but raises both the initial cost of plant and operational cost considerably. The value of LPG recovered should be high enough to widen the operating margins between the processing costs and the market price for which the recovered liquids can be sold. Therefore, the most economic means of extracting this product must be used. This was done using two alternatives; the Conventional Fractionation process and Single column overhead recycle process (SCORE). Both alternatives were simulated with Hysys and are analyzed based on product recovery level, energy required and fixed capital cost. There are two feeds to the plant, one from the natural gas wells and the other from dehydrating units of natural gas processing plants with a total flow rate of 6.99 MMSCFD. Analysis of result from modeling shows that Single column overhead recycle process has a total product recovery of 97.2 % while Conventional fractionation process has a total recovery of 88.5 %, the require energy margin between the alternatives is about 38.9 % in favor of conventional process and the fixed capital cost is in the favor of Single column process. Sensitive to choosing the most economic option of LPG recovery between the conventional process and SCORE process is the recovery level of LPG from each of the options, total energy required and the cost of the equipment. From the analysis, it shows that, it is more economical to use the Single column overhead recycle process, as compared to conventional fractionation process.

This paper suggests that the environmental and commercial features of shale gas extraction do not warrant a significantly different fiscal regime than recommended for conventional gas. Fiscal policies may have a role in addressing some environmental risks (e.g., greenhouse gases, scarce water, local air pollution) though in some cases their net benefits may be modest. Simulation analyses suggest, moreover, that special fiscal regimes are generally less important than other factors in determining shale gas investments (hence there appears little need for them), yet they forego significant revenues.

The most capital-intensive phase of technology LNG has been found: it is the main cryogenic heat exchanger with mass-dimensional parameters which depend on the efficiency of gas pre-cooling process. Improving the efficiency of this process will reduce the cost of LNG production, hardware costs and size of the equipment. The analysis showed that carbon dioxide with triple point coordinates can be used for natural gas pre-cooling before supplying it into the cryogenic exchangers. The usage of carbon dioxide at the triple point coordinates increases the efficiency of pre-cooling due to the energy of the phase transition.

The most capital-intensive phase of technology LNG has been found: it is the main cryogenic heat exchanger with mass-dimensional parameters which depend on the efficiency of gas pre-cooling process. Improving the efficiency of this process will reduce the cost of LNG production, hardware costs and size of the equipment. The analysis showed that carbon dioxide with triple point coordinates can be used for natural gas pre-cooling before supplying it into the cryogenic exchangers. The usage of carbon dioxide at the triple point coordinates increases the efficiency of pre-cooling due to the energy of the phase transition.

hoje um museu, ela e outras pequenas geradoras formam o complexo de Marmelos ainda em operação (Marmelos 2), na categoria definida pela legislação atual como "Pequenas Centrais Hidrelétricas" (PCHs). Este modelo de aproveitamento hidrelétrico tem sido defendido por vários argumentos, dentre os quais, ser potencialmente menos agressivo ao ambiente e ter custo reduzido; é considerado um investimento de pequena monta. A questão da sustentabilidade econômica e ambiental de tais empreendimentos, à luz dos estudos de caso sobre esta experiência pioneira, foi o objeto de nossas reflexões. Os autores são membros de uma equipe multidisciplinar (historiadores

Flare gas recovery system (FGRS) is a new normal in oil and gas industries and it is designed mainly to capture and reuse gases that are routinely manifolded into flare system for combustion. The recovered gases do not only reduce monumental pollution to the environment but also widen the profit margin of the processes that produce them thus incentivising it for industry-wide adoption especially for refineries and petrochemicals which hardly break-even due to high production cost and competitively emerging energy alternatives. This research work attempted to produce 430,600 kg/hr FGRS for a refinery in south-south Nigeria by simulating the plant which recovers certain flare gases from the flare system header and reroutes them as recycles for use in the refinery, Petrochemical plants and other industries. The simulation tool deployed for the purpose is Unisim Design 471 with flare data obtained from Fluid catalytic cracking Unit of the refinery's fuels plant and was run in steady state using Peng-Robbinson fluid package to retrieve methane, ethane, propane, butane, isobutane and debutanized products from the flare stream. The simulated plant shows an average percentage product recovery of 94%. Installation of the FGRS has prospect of reducing carbon dioxide emission to the environment by about ten million tonnes per year. The simulation predicted very high products tonnage for the recovery plant which if implemented would return the said refinery to the path of profitability and compliance to global zero flaring mandate.

Water removal from natural gas is an inevitable process in natural gas industry. Tri-Ethylene Glycol (TEG) plant is the most common and economical process for the dehydration of natural gas. In this work, a domestic TEG dehydration unit is simulated to determine the effect of various parameters on water content of the outlet dehydrated gas. The key feature of this work is the use of Relative Sensitivity Function (RSF) to optimize the whole plant. RSF led into a reduction in the water content of dehydrated gas, TEG circulation rate, and re-boiler duty. The final results revealed that relative sensitivity analysis is a convincing method to determine the best operating conditions and to evaluate the effect of various parameters on water content of the dried gas leaving the absorber column.

Mundialmente la segunda tecnología más empleada para licuar el Gas Natural es la de Cascada Optimizada de Phillips®. En este trabajo se realizó la simulación de un proceso en cascada con refrigerantes puros (propano, etileno y metano). Se usó el simulador de procesos comercial PRO/II® comparando los modelos termodinámicos de Peng-Robinson (PR) y (COP global) para el ciclo igual a 0,52. Luego se estudió la posibilidad de emplear CO 2 como refrigerante del proceso de licuefacción considerando tres escenarios: 1) como sustituto del propano, para el cual se obtuvo un COP global como pre-enfriamiento del ciclo en cascada, para el cual se alcanzó un COP global completo con las tres cascadas. En este último escenario el COP global fue 0,46 incluyendo el trabajo del compresor del ciclo de CO 2

Exergy rate profiles, exergetic efficiency and irreversibility were used to examine the driving forces in multicomponent distillation system with the view to identifying feasible and efficient operating parameters. The mixture used comprised of 5% propane, 15% iso-butane, 25% nbutane, 20% iso-pentane and 35% n-pentane. Operating variables were feed temperature (-30 oC and -80 oC), pressure (800 kPa and 1200 kPa), and reflux-ratio (2 and 6). Stage-by-stage system exergy analysis was estimated. Column profiles of base case -30 oC, -80 oC, -30 oC-reflus ratio 6, -80 oC reflux ratio 6 and base case reflux ratio 6 did not crossed thus are thermodynamically feasible. Base case -30 oC-reflux ratio 2, -80 oC-reflux ratio 2, and base case-reflux ratio 2 were crossed and constricted and are infeasible. Base case results gave efficiency of 81.7% at depropanizer and 65.2% at debutanizer. Base cases sensitivity results with -30 oC, -80 oC and reflux ratio 6, efficiency range 57.40 – 70% and 65.2...

This paper reports on research sponsored by the U.S. Department of Energy (USDOE) to assess factors influencing enhanced gas recovery (EGR) and CO 2 storage in selected gas shales in the Eastern USA [1]. The paper also summarizes work sponsored by the IEA Greenhouse Gas R&D Programme (IEAGHG), which builds upon the lessons learned regarding EGR and CO 2 storage in the U.S., combined with a global assessment of shale gas potential [2], to develop a high-level estimate of the potential for EGR and CO 2 storage in gas shales globally [3]. In total, the four selected shale gas plays in the Eastern USA addressed in this assessment cover an area of 470,000 square kilometres (182,000 square miles). These shales may contain an estimated 170 trillion cubic meters (Tcm) (6,000 trillion cubic feet (Tcf)) of gas in place, and have a maximum theoretical storage capacity of over 600 billion metric tons (gigatonnes, Gt). Accounting for assumptions about the portion of the gas in-place in these shale plays that may be recoverable, and the portion of this recoverable resource that could be economic to produce using EGR techniques with CO 2 injection, nearly 34 Tcm (1,200 Tcf) of EGR potential is estimated to be associated with the injection of CO 2 into these shale gas plays. Of this, 13 Tcm (460 Tcf) could be economic to recover with reasonable gas prices and/or modest incentives. This could facilitate the storage of nearly 50 Gt of CO 2. Building upon this work, as well as an assessment by the U.S. Energy Information Administration (USEIA) that provides a "firstorder" view of the gas in-place and technically recoverable resource for 48 shale gas basins and 69 shale gas formations in 32 countries, an estimate was developed of the global the potential for EGR and CO 2 storage in gas shales [3]. An estimated 188 Tcm (6,600 Tcf) of shale gas resources are potentially technically recoverable globally (not including consideration of the potential EGR realized as a result of CO 2 injection in shales). This could facilitate the potential storage of 740 Gt of CO 2 in gas shales. Of this, as much as 71 Tcm (2,505 Tcf) could be economic to produce with EGR, and could facilitate the economic storage of 280 Gt of CO 2 .

Water Distribution Networks (WDNs) are considered one of the most important water infrastructures, and their study is of great importance. In the meantime, it seems necessary to investigate the factors involved in the failure of the urban water distribution network to optimally manage water resources and the environment. This study investigated the impact of influential factors on the failure rate of the water distribution network in Birjand, Iran. The outcomes can be considered a case study, with the possibility of extending to any similar city worldwide. The soft sensor based on the Adaptive Neuro-Fuzzy Inference System (ANFIS) was implemented to predict the failure rate based on effective features. Finally, the WDN was assessed using the Failure Modes and Effects Analysis (FMEA) technique. The results showed that pipe diameter, pipe material, and water pressure are the most influential factors. Besides, polyethylene pipes have failure rates four times higher than asbestos-cement ...

El gas natural licuado (GNL), gas natural en fase liquida a una temperatura de –161°C y presion atmosferica, es la forma mas rentable de transportar este combustible, cuando se tienen distancias superiores a los 3.800 km desde la fuente hasta los mercados de consumo debido a la reduccion de su volumen (600 veces). La produccion de GNL es una tecnologia madura, con mas de 30 anos de experiencia, respaldada mundialmente por diferentes procesos comerciales. Este trabajo se baso en el estudio de las tecnologias de licuefaccion existentes para aplicarlos al proyecto de nuestro pais, teniendo en cuenta los procesos comercialmente disponibles que se encuentran en la industria de GNL: proceso con intercambiadores de tubos en espiral, de cascada optimizada, el triple ciclo, entre otros. Se realizo un analisis comparativo de variables tecnicas y economicas de tres tecnologias seleccionadas, tales como: flexibilidad, eficiencia, grado de madurez, aspectos ambientales, costo de capital, entre o...

Flopaams polymers are water-soluble polymers which display a significant degree of sensitivity to salinity changes as they consist of negative charges along their molecular chains. Electrostatic charges present along the backbone of a polymer molecule causes stretching (which results from repulsion of electrons) of the polymeric chains in water. The repulsion of these charges extends the molecular chain and gives it a rigid structure which results in high viscosities. When these polymers are exposed to a saline environment, the opposite charged cations present in salts makes the polymers loose their charges and the molecules loose their rigidity and become flexible. This drastically changes the physical properties of the solution of which a reduced polymer viscosity is easily noticed. Small Amplitude Oscillatory Shear (SAOS) material functions such as: Complex Viscosity Coefficients (alternatively, storage and loss moduli) were measured for four (4) Flopaam Acknowledgement I would love to express my profound gratitude to my thesis supervisor, Associate Professor Dmitry Shogin for being a mentor and a role model to look up to, continually challenging me, explaining complicated concepts in the most easy-to-understand manner, painstakingly scrutinizing this work, and spontaneously creating time for my unscheduled visits.

Summary The performance of oil-well cement is altered if contaminated by spacers. Very few studies in the literature are found on this topic, in particular for newly developed microemulsion spacers. Therefore, it is worth investigating the properties of cement contaminated with spacers. In this study, material characterization techniques including chemical shrinkage, ultrasonic pulse velocity (UPV), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and nitrogen adsorption (NAD) were used to study the hydration and microstructure of contaminated cement. Results showed that the studied microemulsion spacer was less compatible with the cement slurry than the conventional one. The microemulsion spacer has complex effects on cement hydration: it slightly enhances hydration for the low dosage but can retard hydration at the early ages and accelerate hydration in the later ages with the increase of dosage. The conventional spacer caused early acceleration of cement hydr...

The primary function of natural gas well cementing is to provide downhole zonal isolation. However, the residual non-aqueous drilling fluid in cement and on the surface of the casing can weaken the bond of hardened cement to the casing. In this paper, the amount of remaining drilling fluid both in cement and on the casing is quantified by the fluorescent dye method, which is verified by other two methods, mass difference and laser scanning. The essential factor-surface roughness that can significantly affect the amount of residual drilling fluid-is investigated. Results show good correlations between the thickness of the remaining drilling fluid and the surface roughness. The comparison of mud removal efficiency of two commercial spacers indicates that microemulsion can remove more drilling fluid than the common spacer, as pointed out in the literature; however, microemulsion is also apt to remain on the casing and thus reduce the bonding between cement and the casing.

Se plantea el siguiente documento como una versión dirigida a personas que se inician en el campo de la investigación. Se describen los factores involucrados en una medición y se presentan los criterios para expresar los resultados. Se espera que el investigador pueda centrar su atención en todas aquellas contribuciones mayores, evalúe y exprese la incertidumbre de las medidas realizadas.Abstract. The document is a person-version for beginners in the field of research. The factors involved in a measurement are described and the criteria for expressing the results are presented. The investigator. It is waiting that the researcher can center its attention who after minimally observing all possible sources of uncertainty, and with sufficient expertise, he or she can center the attention on all major contributions, evaluates and expresses the uncertainty in all.Maestrí

CENTRO NACIONAL DE VERIFICACION DE MAQUINARIA Siguiendo los criterios de la Guia ISO (GUM) y de la norma UNEEN 1076:2010, este documento aporta informacion para la determinacion de la incertidumbre de medida de agentes quimicos presentes en la forma de gases o vapores, a partir de la informacion de validacion de los Metodos de Toma de muestra y Analisis (MTA) del INSHT. Determination of the uncertainty of chemical agents’ measurement (I): gases and vapours Determination de l’incertitude de mesure d’agents chimiques (I) : gaz et vapeurs 931