Victor R. Ruiz Ahón

Fluminense Federal University | UFF · Chemical and Petroleum Engineering

Surface tension represents a significant thermodynamic property of fluids that impact several processes in petroleum engineering and science. Accurate estimates of its values are required for the correct application and development of processes such as flow processes and oil recovery. In this regard, predictive models for surface tension represent...

Aquecendo e comprimindo um composto líquido ou gasoso acima da sua temperatura e pressão crítica, origina-se a fase densa. Nesta região, a densidade do gás aproxima-se a de um líquido, porém, com uma viscosidade próxima a de um gás. O objetivo deste estudo é realizar uma análise termodinâmica do escoamento de gases densos, visando compreender as va...

Accurate determination of petroleum fluid properties, such as viscosity, bubble point pressure and compressibility, is a very important task for several applications in the oil and gas industry. With the advancement of new computational tools and machine learning techniques, Artificial Neural Networks have emerged as an alternative to mathematical...

• Artificial neural networks could improve the prediction of surface tension. • Surface tension of pure organic compounds was accurately predicted by the proposed ANN model. • Over than 1,600 compounds were considered. • The main advantage of the proposed model is its high accuracy values for a wide range of compounds. • The absolute average deviat...

The cryogenic extractive distillation process for CO 2-ethane separation from natural gas involves four distillation columns in series and a rather high amount of energy from boiler and refrigeration compressors. This study proposes the intensification of a real plant located in China using a vapor recompression (VR) strategy to revamp it. The conv...

RESUMO-Aquecendo e comprimindo um composto líquido ou gasoso acima da sua temperatura e pressão crítica, origina-se a fase densa. Nesta região, a densidade do gás aproxima-se a de um líquido, porém, com uma viscosidade próxima a de um gás. O objetivo deste estudo é analisar termodinamicamente o escoamento de gases densos para compreender como a den...

As computers become more powerful and efficient at processing data, more robust computational models can be developed that can accurately represent the interactions between variables within a system. In this sense, the present work proposes an artificial neural network (ANN) approach for estimating light hydrocarbon viscosity. A dataset of over 500...

Cementing is an extremely important step in the well construction process. It has important objectives such as hydraulic sealing to prevent migration of undesired fluids from the formations and their collapse. One of the methods to verify the quality of cementat jobs is running acoustic logging tools such as CBL/VDL and ultrasonic and inferring zon...

Water-in-oil (W/O) emulsions are present in some stages of exploration and operation of oil fields. Therefore, it is important to define the dynamic viscosity behavior of these emulsions for flow assurance purposes. This study applied an Artificial Intelligence Algorithm called Artificial Neural Network in order to predict the emulsion dynamic visc...

Brazilian offshore activity has increased substantially in recent years, with many new oil fields being developed, and there is also a significant investment in the maintenance and optimization of existing ones. In all cases, the presence of water-in-oil emulsions during oil production is a critical issue, causing pressure drops in subsea lines and...

The present work proposes an automatic cement evaluation system for oil wells, through the interpretation of geophysical well logging (VDL – variable density log) using one of the most popular deep neural networks, the Convolutional Neural Network (CNN or ConvNet). It is a class of deep neural networks that specializes in processing data that has a...

The main equipment in a refinery is the atmospheric distillation column, whose objective is to separate the oil into its fractions before any chemical transformation. The design of this equipment is quite complex and demands an optimal choice of the variables that can be manipulated to adjust the flow rate and composition of the different products....

Oil and gas mixtures are the most common ones among the two-phase flows present in the petroleum industry and that, to a great extent, occur in horizontal pipelines. Therefore, several authors seek a better understanding of the characteristics of pressure profiles related to such flows. Among the various correlations developed, that of Lockhart and...

Emulsões são dispersões relativamente estáveis de gotas de determinado líquido (fase dispersa) em outro líquido (fase contínua) que são normalmente imiscíveis, mas que podem se tornar uma mistura homogênea. No processo de exploração e extração de petróleo, principalmente em campos de exploração maduros, é possível observar o aumento da produção de...

Devido à diversidade de propriedades físicas e químicas dos fluidos de reservatório de petróleo, o conhecimento das relações de pressão-volume-temperatura (PVT) é essencial para solução de problemas de engenharia. Uma dessas propriedades é o fator de compressibilidade (Z), que reflete o quanto o gás real se desvia do gás ideal a uma dada pressão e...

O aumento crescente no consumo do petróleo no mundo expandiu as explorações de campos petrolíferos no mar, em águas cada vez mais profundas e demandou formulações de fluidos de perfuração cada vez mais sofisticadas e caras. Os fluidos de perfuração à base óleo foram muito utilizados ao longo de anos por possuírem as propriedades desejadas à perfura...

Thermodynamic models were created with the aim of minimizing experimental or pilot testing of a process when information is available. The description of the thermodynamic behavior of physical systems is of great relevance for the design and analysis of industrial processes. The main objective is to allow understanding, developing and changing proc...

Ever since the work of van der Waals in 1873, the modeling of systems containing water and hydrocarbons is still a key point in the development of new thermodynamic approaches and technologies. The applicability, reliability and accuracy of models for estimating the physical properties and phase behavior of fluids depend on the comprehensiveness of...

In this work, the ϕ-ϕ approach is used to describe the behaviour of vapour-liquid equilibrium of mixed-solvent electrolyte solutions by means of EoS/GE type models. The approach in this article consists in the inclusion of activity coefficient information in the Peng-Robinson equation of state through three different mixing rules: Heidemann-Kokal (...

To characterize a porous medium, it is essential to determine the geometry of its pore space as it controls key properties such as permeability. A standard approach is to saturate the pore space with a fluid and perform NMR relaxation measurements. The standard measurements are sensitive to the low-lying diffusion eigen-modes and they allow an esti...

Phase equilibria calculation is a tool with great potential for application in separation processes in the chemical industry. The ability to predict Liquid-Liquid Equilibria (LLE) in multicomponent systems using parameters estimated for Vapor-Liquid Equilibrium could be very useful for cases that lack this kind of experimental data. With that inten...

Efficient prediction of liquid dropout on reservoir fluids of gas condensate samples is of great importance to oil and gas companies and also for studies on transport phenomena. However, this thermodynamics modeling is still a challenging task and require not only an accurate model for both phase equilibrium and volumetric properties calculation, b...

Pressure-Volume-Temperature correlations are essential for estimating the required parameters necessary for the identification of reservoir fluid properties when experimental laboratory data are not readily available. Although several models have been published for different oil fields, there is a lack of studies addressing the Brazilian pre-salt r...

Electrolyte systems are of great interest because of its intrinsic non-ideality. In the beginning, the most common way to proceed the treatment of electrolytic solutions was the utilization of activity coefficient models. They have been often preferred because of the wide range of parameters available in the literature for their application. The ma...

O presente trabalho apresenta o desenvolvimento de um programa computacional capaz de determinar o ponto de operação de um poço de petróleo, através das curvas que representam o desempenho do reservatório (IPR) e da coluna de produção de um poço (TPR). O simulador é composicional e está baseado no uso da equação de estado cúbica de Peng-Robinson pa...

In this work, a ϕ-ϕ approach is tested in the description of vapor-liquid equilibrium of 18 different binary systems by means of EoS/GE type models. These models combine the potentialities of the Peng-Robinson cubic equation of state and the UNIQUAC local composition model. The focus is on the Heidemann-Kokal Mixing Rule, whose derivation is presen...

Dynamic optimization of gas lift process (GLP) aims to compute control optimal trajectories of gas injection flow rate so that the oil production can be maximized. It has been observed that dynamic optimization of GLP is little discussed in the recent literature since most of the papers have focused on steady state optimization and multivariable pr...

Neste trabalho, o desempenho de um modelo termodinâmico do tipo EdE/G E , por metodologia de Heidemann-Kokal, foi avaliado na modelagem do equilíbrio líquido-vapor de sistemas binários. O modelo alia as potencialidades da equação de estado cúbica de Peng-Robinson (PR) com o modelo de composição local UNIQUAC. Nesta Parte 1, foram avaliados sistemas...

Neste trabalho, o desempenho de um modelo termodinâmico do tipo EdE/GE, por metodologia de Heidemann-Kokal, foi avaliado na modelagem do equilíbrio líquido-vapor de sistemas binários. O modelo alia as potencialidades da equação de estado cúbica de Peng-Robinson (PR) com o modelo de composição local UNIQUAC. Nesta Parte 1, foram avaliados sistemas s...

Nos últimos anos, vem sendo observada uma tendência de aumento na severidade química e física dos ambientes encontrados na indústria de petróleo e gás natural. Por causa disso, há um crescente interesse sobre o estudo de sistemas contendo ácido sulfídrico (H2S), gás carbônico (CO2), sais e água. Atualmente, uma grande quantidade de trabalhos experi...

INTRODUÇÃO Fluidos de reservatório de petróleo são misturas complexas de hidrocarbonetos, que podem ser divididos em frações leves e frações pesadas. As frações leves contêm gases e hidrocarbonetos de baixa massa molar, como CO 2 , H 2 S, N 2 , C 1 , C 2 , C 3 e n-C 4. Já as frações pesadas contêm uma extensa variedade de compostos parafínicos, naf...

Cubic equations of state are largely used in the chemical industry, especially in the oil and gas industry. The preference for this type of model is, mainly, due to its simplicity and large application ranges. However, such models exhibit acknowledged deficiencies in volumetric properties prediction for liquid phases. Each year, new modifications a...

Since Peng and Robinson proposed their cubic equation of state (cubic EoS) in 1976, several attempts were made to improve its performance and to extend its application to an increasing number of substances. Many authors have focused in vapor pressure calculation, what in great part signifies the proposal of a new alpha function for the attractive t...

RESUMO – Equações de estado cúbicas são amplamente utilizadas na indústria química, especialmente na indústria de petróleo e gás. A preferência por esse tipo de modelo se deve, principalmente, à sua simplicidade e larga faixa de aplicação. No entanto, tais modelos apresentam reconhecidas deficiências na predição de propriedades volumétricas, especi...

Due to the intensification of environmental constrains combined with the tendency to process crude oils with high C/H, S/H ratios and natural gas with increasing CO2/CH4 and H2S/CH4 ratios, acid gas removal from gas streams is probably the most required process in the petroleum and gas industries nowadays. Absorption with aqueous alkanolamines such...

Thermodynamic hydrate inhibitors such as methanol, ethanol, (mono) ethylene glycol (MEG), and triethylene glycol (TEG) are widely used in the oil and gas industry. On modeling these compounds, we show here how the CPA equation of state was implemented in an in-house process simulator as an in-built model. To validate the implementation, we show cal...

A method for analysis of the electric potential profile in saline solutions was developed for systems with one or two infinite flat plates. A modified Poisson-Boltzmann equation, taking into account nonelectrostatic interactions between ions and surfaces, was used. To solve the stated problem in the steady-state approach the finite-difference metho...

Since the discovery of the Pre-Salt layer in Brazilian waters, production of high gas–oil ratio (GOR) has increased considerably. This gas has a high content of water, CO2, and sometimes H2S. A study in different conditions was conducted using several equations of state (EoS) such as Peng–Robinson, GERG-modified Peng–Robinson (PR-ISO-04), Soave–Red...

PETROBRAS is an energy company, which operates in oil and gas production and refining, petrochemicals and biofuels production, but it is also a technology developer. In this sense, in-house process simulators are strategic to standardize and disseminate technological innovations amongst engineers of the entire company. Due to the need to have a u...

A previously developed pseudo-component adaptive characterization method was applied to the multistage separation of continuous mixtures. The objective of this new approach is to provide an adaptive scheme for the process simulation of continuous multicomponent mixtures that can be accurate using few pseudo-components. For illustration purposes, th...

Petrobras — Petroleo Brasileiro S.A., is an active player in research, oil and gas exploration and processing, petrochemical and fertilizers industries as well as in bio fuels production. As the process designs are elaborated with a high degree of innovation, the utilization of an in-house process simulator has strategic advantages. PETROX — Petrob...

An optimization procedure for increasing the methanol production in synthesis loops with quench reactors is presented. The process decision variables are represented by a set of split fractions of the reactor feed to the catalyst beds. The optimization routine is coupled to a steady-state model of the methanol synthesis loop. Numerical results illu...

The kinetics of the Fischer-Tropsch reaction over a Co/Nb2O5 catalyst in a fixed bed reactor was investigated experimentally. Experiments were carried out under isothermal and isobaric conditions (T=543 K, P=2.1 MPa) and under different conditions of several H2/CO feed molar ratio (0.49–4.79), space velocities (0.2–3.8 h−1), mass of catalyst (0.3–1...

This work presents an alternative structure for multivessel batch distillation and focuses on the determination of an optimal programming for it. The system is composed by a set of heated or cooled vessels connected by total reflux distillation cascades. This structure is able for separating multicomponent mixtures achieving simultaneously desirabl...

The standard enthalpy of formation, estimated by the group contribution method of Benson, and by semi-empirical molecular simulation methods has been compared with experimental data. Benson's method estimates hydrocarbon enthalpies satisfactorily. The Benson's estimates of enthalpies of free radicals are in general superior to the molecular simulat...

Continuous Mixtures are mixtures of so many components that is no longer useful to distinguish among chemical species. Instead, an index is chosen to characterize each molecule, such as carbon atoms in each substructure, Chromatographic retention time or normal boiling point and the continuity of this index is admitted. The present work aims the ma...

A new product distribution quasi-steady-state model was proposed for the Fischer–Tropsch (FT) synthesis in slurry reactors, being applicable to their transient simulation. It may consider two chain propagation mechanisms or sites and the possibility of 1-olefin readsorption with secondary reactions, recovering the Anderson–Schulz–Flory (ASF) model,...

This work addresses the problem of optimal programming of multi-component batch distillation columns with a single vessel (batch rectifier, batch stripper, middle vessel and extractive middle vessel) so as to maximize an annualized profit function. A smooth price function is formulated for product valuation, allowing to release traditional purity c...

In this work, several simulated annealing algorithms presented in the literature as solutions to different problems were compared in the scheduling of multiproduct serial batch plants. A systematic performance study of the original algorithm, based on the Boltzmann statistics, and a recently proposed algorithm, based on the Tsallis statistics, were...

The estimation of transport properties is of great importance to the design and simulation of distillation columns, especially when heavy cuts, as Brazilian oil feedstocks, are being processed. The viscosity correlations available in the literature have been developed using mostly data from light Arabian oils. Due to that fact, they do not well des...

For understanding the interaction between process conditions and the mechanical behavior of semi batch reactors dedicated to the pyrolysis and carbonization of petroleum distillation residues, it is necessary to select a simple method of characterization of residues, an effective kinetic model of pyrolysis and suitable methods for estimating accura...

A busca por uma maior eficiência energética tem sido uma preocupação constante nas atividades industriais do setor de petróleo e gás. O aumento dos custos de energia, a pressão pela redução das emissões de carbono para atmosfera e o aumento da competitividade a nível global são fatores preponderantes neste processo. Em uma refinaria de petróleo, o...

O aumento dos custos de energia, a necessidade de redução das emissões de CO 2 e o acirramento da competição entre as empresas são manifestações típicas do atual cenário que a indústria do petróleo enfrenta. Como uma das conseqüências destes novos desafios, a racionalização do consumo de energia tornou-se uma necessidade. Entre os vários avanços te...