Application of GC-PC-SAFT EoS to Organic Sulfur Compounds

International audienceÉquations d'état en thermodynamique: des équations cubiques aux équations issues de la thermodynamique moléculaire Design and optimization of separation processes require accurate knowledge of the thermodynamic properties and phase equilibria of involved pure compounds and mixtures. Thermodynamic models are thus needed to determine these properties. Model development relies on not only appropriate theory but also experimental data. However, for the organic sulfur compounds which are commonly found in diverse industrial sectors, few or even no experimental data exist in the literature. Therefore, models with predictive features may act as an alternative to handle engineering purposes. Statistical Associating Fluid Theory (SAFT) equation of states (EoS) has been proved to be a powerful tool for modeling phase equilibria, as statistic mechanics and molecular theory were incorporated into the development. In this work, the Perturbed-Chain SAFT (PC-SAFT) EoS [1] was combined with the Group Contribution method proposed by Tamouza et al. [2]. The predictive model (named GC-PC-SAFT) was applied to investigate two series of typical organic sulfur compounds: sulfide (R-S-R') and 1-thiol (R-SH). The group parameters of (S) and (SH) were fitted to vapor pressure and liquid density data (from [3]) of 9 sulfides and 7 1-thiols, respectively. The regression results show that the average deviations on vapor pressure are generally lower than 5%, while those on liquid density are generally lower than 2%

An improved static–analytic apparatus for vapor–liquid equilibrium (PTxy) measurement using modified in-situ samplers

International audienceAn improved apparatus based on the static-analytic method for reliable vapor-liquid equilibrium (VLE) data measurement is presented in this work. It has been applied to investigate systems containing organic sulfur compounds. New sampling mechanisms were combined with ROLSI TM capillary samplers to achieve on-line sampling for both vapor and liquid phases in a pressure range between 0.1 and 10 bar. Phase samples were directly sent to a gas chromatograph for composition analysis. The equipment was tested against other commonly used experimental methods in this pressure range on the (n-butane + ethanol) and (diethyl sulfide + ethanol) systems. The obtained data were correlated by Wilson model and compared with existing data. The improved apparatus has shown comparable performances to existing methods, while showing some advantages such as complete PTxy phase measurements and less product consumption. After the validation step, additional VLE data for binary systems of interest, (diethyl sulfide + n-butane) and (1-pentanethiol + 1-pentanol), were reported and modeled in this work

A New Static Analytic Apparatus for Complete Determination of Phase Equilibrium Data from Sub-atmospheric Pressures up to 10 bar

International audienceA new static-analytic apparatus equipped two ROLSI TM capillary samplers was presented.The proposed improvements allow ROLSI TM to perform in-situ sampling even at P < P carrier gas. The apparatus has shown comparable performances to existing methods, while showing some advantages. Two binary systems of interest were investigated. New systems are expected to be investigated for various applications in chemical engineering. The liquid sampling mechanism is expected to be used for liquid-liquid equilibrium measurement

Role of Impurities on CO2 Injection: Experimental and Numerical Simulations of Thermodynamic Properties of Water-salt-gas Mixtures (CO2 + Co-injected Gases) Under Geological Storage Conditions

International audienceRole of impurities on CO 2 injection: experimental and numerical simulations of thermodynamic properties of water-salt-gas mixtures (CO 2 + co-injected gases) under geological storage conditions Abstract Regarding the hydrocarbon source and CO 2 capture processes, fuel gas from boilers may be accompanied by so-called "annex gases" which could be co-injected in a geological storage. These gases, such as SOx, NOx, or oxygen for instance, are likely to interact with reservoir fluids and rocks and well materials (casing and cement) and could potentially affect the safety of the storage. However, there are currently only few data on the behaviour of such gas mixtures, as well as on their chemical reactivity, especially in the presence of water. One reason for this lack comes from the difficulty in handling because of their dangerousness and their chemical reactivity. Therefore, the purpose of the Gaz Annexes was to develop new experimental and analytical protocols in order to acquire new thermodynamic data on these annex gases, in fine for predicting the behaviour of a geological storage of CO 2 + co-injected gases in the short, medium and long terms. This paper presents Gaz Annexes concerning acquisition of PVT experimental and pseudo-experimental data to adjust and validate thermodynamic models for water / gas / salts mixtures as well as the possible influence of SO 2 and NO on the geological storage of CO 2. The Gaz Annexes s new insights for the establishment of recommendations concerning acceptable content of annex gases

Absorption des mercaptans dans des solutions aqueuses d'amines

International audienceLe traitement des gaz et des hydrocarbures liquides reste encore un domaine de recherche d'intérêt. En effet, l'exploration souterraine a mis en évidence de nouveaux gisements d'hydrocarbures dont il faut assurer le traitement avant utilisation. Ce traitement consiste, en partie, à éliminer les gaz acides (dioxyde de carbone (CO 2) et sulfure d'hydrogène (H 2 S)) et les produits soufrés (mercaptans (RSH), sulfure de carbonyle (COS), etc…). Actuellement, l'adoucissement du gaz naturel par contact avec des solutions d'amines est la technique la plus utilisée et l'innovation provient majoritairement de la création de nouvelles molécules d'amines de plus en plus réactives et sélectives. Parmi les amines les plus connues, nous pouvons citer la monoethanolamine (MEA), la diéthanolamine (DEA) et la N-méthyldiethanolamine (MDEA). Les données concernant les équilibres de phases: gaz acides + espèces soufrées + hydrocarbures + amines sont indispensables en vue d'une conception plus économique de nouvelles usines de traitement par les amines, mais aussi dans le but d'améliorer l'efficacité des unités existantes. A notre connaissance, peu de données de solubilité des mercaptans dans des solutions aqueuses d'alcanolamines, en présence de gaz acides, sont disponibles dans la littérature. L'objectif de cette présentation est de présenter une campagne de mesures expérimentales effectuées au sein du CTP. Ces mesures incluent des équilibres liquide-vapeur et de coefficients de partage des espèces soufrées dans diverses solutions d'alcanolamines en présence et en absence des gaz acides

Physicochemical Properties of Gas

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Alkane solubilities in aqueous alkanolamine solutions with CPA EoS

International audienceAbsorption with aqueous alkanolamine solution is often used for acid gas removal processes. Thermodynamic model is very important to predict phase behaviour for designing and optimizing acid gas absorption units. To estimate alkanes losses in these processes, the knowledge of alkanes solubility in aqueous alkanolamine solutions is essential. In the present work, Cubic-Plus-Association Equation of State (CPA EoS) was applied to represent alkanes solubility in aqueous alkanolamine. The Average Relative Deviation on alkanes solubility in aqueous alkanolamine solution is less than 15%. Due to our model, the temperature of alkanes minimum solubility in pure water and alkanolamine solutions are correctly predicted. Water content is also well predicted at Vapour Liquid Equilibrium condition

Thermodynamic Study of Mixtures of Compounds Present During the Carbon Dioxide Capture, Transport and Storage

International audienceWithin the fight against global warming and the reduction of greenhouse-gases emission, research has been particularly intense over the last years to develop efficient processes of carbon dioxide captures. Indeed, along with carbon dioxide and water, a great number of compounds such as O2, N2, Ar, SOx, NOx, H2 and CO can be present at different levels of concentration. The objective of this communication is to provide new sets of data to characterize phase equilibrium of these systems for the development of geological storage technologies. So, Isothermal vapour-liquid equilibrium data are reported for the following systems (SO2-O2-N2 and CO2-O2- H2O). The pressure and temperature ranges for this study are 6-18 MPa and 323-373 K, respectively. All measurements were carried out using an apparatus based on the "static-analytic" method

Plasma aided combustion of air-natural gas mixture using an atmospheric pressure rotating discharge for vehicle applications

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