When first received by a refinery, the crude oil usually contains some water, mineral salts, and sediments. The salt appears in different forms, most often times it is dissolved in the formation water that comes with the crude i.e. in brine form, but it could also be present as solid crystals, water-insoluble particles of corrosion products or scale and metal-organic compounds such as prophyrins and naphthenates. The amount of salt in the crude can vary typically between 5 to 200 PTB depending on the crude source, API, viscosity and other properties of the crude. For the following reasons, it is of utmost importance to reduce the amount of salt in the crude before processing the crude in the Crude Distillation Unit and consequently downstream processing units of a refinery. 1. Salt causes corrosion in the equipment. 2. Salt fouls inside the equipment. The fouling problem not only negatively impacts the heat transfer rates in the exchangers and furnace tubes but also affects the hydraulics of the system by increasing the pressure drops and hence requiring more pumping power to the system. Salt also plugs the fractionator trays and causes reduced mass transfer i.e. reduced separation efficiency and therefore need for increased re-boiler/condenser duties. 3. The salt in the crude usually has a source of metallic compounds, which could cause poisoning of catalyst in hydrotreating and other refinery units. Until a few years ago, salt concentrations as high as 10 PTB (1 PTB = 1 lb salt per 1000 bbl crude) was acceptable for desalted crude; However, most of the refineries have adopted more stringent measures for salt content and recent specs only allow 1 PTB in the desalted crude. This would require many existing refineries to improve their desalting units to achieve the tighter salt spec. This study will focus on optimizing the salt removal efficiency of a desalting unit which currently has an existing single-stage desalter. By adding a second stage desalter, the required salt spec in the desalted crude will be met. Also, focus will be on improving the heat integration of the desalting process, and optimization of the desalting temperature to achieve the best operating conditions in the plant after revamp.

Chemical absorption and desorption processes are two fundamental operations in the process industry. Due to the rate-controlled nature of these processes, classical equilibrium stage models are usually inadequate for describing the behaviour of chemical absorption and desorption processes. A more effective modelling method is the non-equilibrium rate-based approach, which considers the effects of the various driving forces across the vapour-liquid interface. In this thesis, a new non-equilibrium rate-based model for chemical absorption and desorption is developed and applied to the hot potassium carbonate process CO₂ Removal Trains at the Santos Moomba Processing Facility. The rate-based process models incorporate rigorous thermodynamic and mass transfer relations for the system and detailed hydrodynamic calculations for the column internals. The enhancement factor approach was used to represent the effects of the chemical reactions. The non-equilibrium rate-based CO₂ Removal Train process models were implemented in the Aspen Custom Modeler® simulation environment, which enabled rigorous thermodynamic and physical property calculations via the Aspen Properties® software. Literature data were used to determine the parameters for the Aspen Properties® property models and to develop empirical correlations when the default Aspen Properties® models were inadequate. Preliminary simulations indicated the need for adjustments to the absorber column models, and a sensitivity analysis identified the effective interfacial area as a suitable model parameter for adjustment. Following the application of adjustment factors to the absorber column models, the CO₂ Removal Train process models were successfully validated against steady-state plant data. The success of the Aspen Custom Modeler® process models demonstrated the suitability of the non-equilibrium rate-based approach for modelling the hot potassium carbonate process. Unfortunately, the hot potassium carbonate process could not be modelled as such in HYSYS®, Santos’s preferred simulation environment, due to the absence of electrolyte components and property models and the limitations of the HYSYS® column operations in accommodating chemical reactions and non-equilibrium column behaviour. While importation of the Aspen Custom Modeler® process models into HYSYS® was possible, it was considered impractical due to the significant associated computation time. To overcome this problem, a novel approach involving the HYSYS® column stage efficiencies and hypothetical HYSYS® components was developed. Stage efficiency correlations, relating various operating parameters to the column performance, were derived from parametric studies performed in Aspen Custom Modeler®. Preliminary simulations indicated that the efficiency correlations were only necessary for the absorber columns; the regenerator columns were adequately represented by the default equilibrium stage models. Hypothetical components were created for the hot potassium carbonate system and the standard Peng-Robinson property package model in HYSYS® was modified to include tabular physical property models to accommodate the hot potassium carbonate system. Relevant model parameters were determined from literature data. As for the Aspen Custom Modeler® process models, the HYSYS® CO₂ Removal Train process models were successfully validated against steady-state plant data. To demonstrate a potential application of the HYSYS® process models, dynamic simulations of the two most dissimilarly configured trains, CO₂ Removal Trains #1 and #7, were performed. Simple first-order plus dead time (FOPDT) process transfer function models, relating the key process variables, were derived to develop a diagonal control structure for each CO₂ Removal Train. The FOPDT model is the standard process engineering approximation to higher order systems, and it effectively described most of the process response curves for the two CO₂ Removal Trains. Although a few response curves were distinctly underdamped, the quality of the validating data for the CO₂ Removal Trains did not justify the use of more complex models than the FOPDT model. While diagonal control structures are a well established form of control for multivariable systems, their application to the hot potassium carbonate process has not been documented in literature. Using a number of controllability analysis methods, the two CO₂ Removal Trains were found to share the same optimal diagonal control structure, which suggested that the identified control scheme was independent of the CO₂ Removal Train configurations. The optimal diagonal control structure was tested in dynamic simulations using the MATLAB® numerical computing environment and was found to provide effective control. This finding confirmed the results of the controllability analyses and demonstrated how the HYSYS® process model could be used to facilitate the development of a control strategy for the Moomba CO₂ Removal Trains. In conclusion, this work addressed the development of a new non-equilibrium rate-based model for the hot potassium carbonate process and its application to the Moomba CO₂ Removal Trains. Further work is recommended to extend the model validity over a wider range of operating conditions and to expand the dynamic HYSYS® simulations to incorporate the diagonal control structures and/or more complex control schemes. / http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1350259 / Thesis (Ph.D.) - University of Adelaide, School of Chemical Engineering, 2009

Chemical absorption and desorption processes are two fundamental operations in the process industry. Due to the rate-controlled nature of these processes, classical equilibrium stage models are usually inadequate for describing the behaviour of chemical absorption and desorption processes. A more effective modelling method is the non-equilibrium rate-based approach, which considers the effects of the various driving forces across the vapour-liquid interface. In this thesis, a new non-equilibrium rate-based model for chemical absorption and desorption is developed and applied to the hot potassium carbonate process CO₂ Removal Trains at the Santos Moomba Processing Facility. The rate-based process models incorporate rigorous thermodynamic and mass transfer relations for the system and detailed hydrodynamic calculations for the column internals. The enhancement factor approach was used to represent the effects of the chemical reactions. The non-equilibrium rate-based CO₂ Removal Train process models were implemented in the Aspen Custom Modeler® simulation environment, which enabled rigorous thermodynamic and physical property calculations via the Aspen Properties® software. Literature data were used to determine the parameters for the Aspen Properties® property models and to develop empirical correlations when the default Aspen Properties® models were inadequate. Preliminary simulations indicated the need for adjustments to the absorber column models, and a sensitivity analysis identified the effective interfacial area as a suitable model parameter for adjustment. Following the application of adjustment factors to the absorber column models, the CO₂ Removal Train process models were successfully validated against steady-state plant data. The success of the Aspen Custom Modeler® process models demonstrated the suitability of the non-equilibrium rate-based approach for modelling the hot potassium carbonate process. Unfortunately, the hot potassium carbonate process could not be modelled as such in HYSYS®, Santos’s preferred simulation environment, due to the absence of electrolyte components and property models and the limitations of the HYSYS® column operations in accommodating chemical reactions and non-equilibrium column behaviour. While importation of the Aspen Custom Modeler® process models into HYSYS® was possible, it was considered impractical due to the significant associated computation time. To overcome this problem, a novel approach involving the HYSYS® column stage efficiencies and hypothetical HYSYS® components was developed. Stage efficiency correlations, relating various operating parameters to the column performance, were derived from parametric studies performed in Aspen Custom Modeler®. Preliminary simulations indicated that the efficiency correlations were only necessary for the absorber columns; the regenerator columns were adequately represented by the default equilibrium stage models. Hypothetical components were created for the hot potassium carbonate system and the standard Peng-Robinson property package model in HYSYS® was modified to include tabular physical property models to accommodate the hot potassium carbonate system. Relevant model parameters were determined from literature data. As for the Aspen Custom Modeler® process models, the HYSYS® CO₂ Removal Train process models were successfully validated against steady-state plant data. To demonstrate a potential application of the HYSYS® process models, dynamic simulations of the two most dissimilarly configured trains, CO₂ Removal Trains #1 and #7, were performed. Simple first-order plus dead time (FOPDT) process transfer function models, relating the key process variables, were derived to develop a diagonal control structure for each CO₂ Removal Train. The FOPDT model is the standard process engineering approximation to higher order systems, and it effectively described most of the process response curves for the two CO₂ Removal Trains. Although a few response curves were distinctly underdamped, the quality of the validating data for the CO₂ Removal Trains did not justify the use of more complex models than the FOPDT model. While diagonal control structures are a well established form of control for multivariable systems, their application to the hot potassium carbonate process has not been documented in literature. Using a number of controllability analysis methods, the two CO₂ Removal Trains were found to share the same optimal diagonal control structure, which suggested that the identified control scheme was independent of the CO₂ Removal Train configurations. The optimal diagonal control structure was tested in dynamic simulations using the MATLAB® numerical computing environment and was found to provide effective control. This finding confirmed the results of the controllability analyses and demonstrated how the HYSYS® process model could be used to facilitate the development of a control strategy for the Moomba CO₂ Removal Trains. In conclusion, this work addressed the development of a new non-equilibrium rate-based model for the hot potassium carbonate process and its application to the Moomba CO₂ Removal Trains. Further work is recommended to extend the model validity over a wider range of operating conditions and to expand the dynamic HYSYS® simulations to incorporate the diagonal control structures and/or more complex control schemes. / http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1350259 / Thesis (Ph.D.) - University of Adelaide, School of Chemical Engineering, 2009

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-10-16T12:44:41Z No. of bitstreams: 1 THALITA CRISTINE RIBEIRO LUCAS FERNANDES - DISSERTAÇÃO (PPGEQ) 2017.pdf: 3155230 bytes, checksum: 29997db242a362fb2a65ffda6fcf8ba0 (MD5) / Made available in DSpace on 2018-10-16T12:44:41Z (GMT). No. of bitstreams: 1 THALITA CRISTINE RIBEIRO LUCAS FERNANDES - DISSERTAÇÃO (PPGEQ) 2017.pdf: 3155230 bytes, checksum: 29997db242a362fb2a65ffda6fcf8ba0 (MD5) Previous issue date: 2017-09-27 / CNPq / A hidrodesnitrogenação catalítica é um processo utilizado para remover impurezas de nitrogênio em produtos derivados de petróleo e ocorre mediante o tratamento da carga com hidrogênio a temperatura e pressão elevadas em um reator do tipo tricled-bed. Para otimizar as operações nestes reatores, é necessário que se tenha informações sobre a cinética das várias reações de hidrodesnitrogenação. Entretanto, as equações das taxas das reações não estão disponíveis na literatura. Assim, o objetivo deste trabalho consiste em obter as equações das taxas das reações e os parâmetros cinéticos para a rede reacional dos compostos nitrogenados utilizando o modelo rigoroso de hidrodesnitrogenação do Aspen Hysys como base numérica para as simulações. Experimentos numéricos foram realizados em um reator diferencial no software Aspen Hysys para obter dados de concentração de reagentes e produtos a diferentes alimentações. Diferentes métodos foram utilizados, um método de regressão linear multivariável para obtenção dos coeficientes de regressão, um método de metamodelagem interpoladora estocástica, o Kriging e a otimização do metamodelo Kriging utilizando o método dos mínimos quadrados. Para testar as metodologias propostas, todas as etapas foram aplicadas para um sistema de duas reações simples, uma reversível e outra irreversível, em um reator PFR. Os resultados referentes ao método de regressão linear mostraram que a metodologia pode ser utilizada para estimar parâmetros cinéticos desde que se conheça a equação da taxa correspondente. A comparação entre os dois métodos do tipo Kriging propostos (convencional e otimizado) foi feita a partir de técnicas de análise estatísticas, como o coeficiente de determinação R² e análise de variância (ANOVA). O kriging otimizado mostrou uma melhor aderência aos dados quando comparado com o kriging convencional. / Catalytic hydrodenitrogenation is one process used to remove nitrogen impurities from refinery streams, and it occurs by reacting a given charge with hydrogen at high temperature and pressure in a trickled-bed reactor. In order to optimize the operation of such reactors one needs information about the kinetics of the various hydrodenitrogenation reactions. However, reaction rate expressions are not available in the open literature. Therefore, this work aims at obtaining the reaction rate expressions and parameters for the reaction network of nitrogen compounds using the rigorous hydrodenitrogenation model in Aspen Hysys as the numerical basis for simulations. A differential reactor to simulate the process for different feed streams generated data to estimate of concentration of reagent and products at different feed loads. Three different methods were used, a multivariable linear regression model to obtain the regression coefficients, a stochastic interpolator metamodeling, Kriging and an optimized Kriging with least square method. In a first step, two simple reactions rates were used to test the methodologies in a reactor PFR in Hysys, a reversible and an irreversible. The results showed that linear regression might be use to estimate parameters satisfactory only if you know the reaction rate expression. By using statistical analysis as determination coefficient R² and analyze of variance, ANOVA, it was possible to compare both Krigings (conventional and optimized). Optimized Kriging showed a better adherence to the data when compared to conventional kriging.

Yes / It has been globally recognized as necessary to reduce greenhouse gas (GHG) emissions for mitigating the adverse effects of global warming on earth. Carbon dioxide (CO2) capture and storage (CCS) technologies can play a critical role to achieve these reductions. Current CCS technologies use several different approaches including adsorption, membrane separation, physical and chemical absorption to separate CO2from flue gases. This study aims to evaluate the performance and energy savings of CO2capture system based on chemical absorption by installing an intercooler in the system. Monoethanolamine (MEA) was used as the absorption solvent and Aspen HYSYS (ver. 9) was used to simulate the CO2capturing model. The positioning of the intercooler was studied in 10 different cases and compared with the base case 0 without intercooling. It was found that the installation of the intercooler improved the overall efficiency of CO2recovery in the designed system for all 1-10 cases. Intercooler case 9 was found to be the best case in providing the highest recovery of CO2(92.68%), together with MEA solvent savings of 2.51%. Furthermore, energy savings of 16 GJ/h was estimated from the absorber column alone, that would increase many folds for the entire CO2capture plant. The intercooling system, thus showed improved CO2recovery performance and potential of significant savings in MEA solvent loading and energy requirements, essential for the development of economical and optimized CO2capturing technology.

Yes / Crude oil is an unrefined petroleum composed of wide range of hydrocarbon up to n‐C40+. However, there are also a percentage of light hydrocarbon components present in the mixture. Therefore, to avoid their flashing for safe storage and transportation, the live crude needs to be stabilized beforehand. This paper aims to find the suitable operating conditions to stabilize an incoming live crude feed to maximum true vapor pressure (TVPs) of 12 psia (82.7 kPa) at Terengganu Crude Oil Terminal, Malaysia. The simulation of the process has been conducted by using Aspen HYSYS. The obtained results illustrate that the simulation data are in good agreement with the plant data and in particular for the heavier hydrocarbons. For the lighter components, the simulation results overpredict the plant data, whereas for the heavier components, this trend is reversed. It was found that at the outlet temperature (85–90°C) of hot oil to crude heat exchanger (HX‐220X), the high‐pressure separator (V‐220 A/B) and the low‐pressure separator (V‐230 A/B) had operating pressures of (400–592 kPa) and (165–186 kPa), respectively, and the live crude was successfully stabilized to a TVP of less than 12 psia. The impact of main variables, that is, inlet feed properties, three‐phase separators operating pressure, and preheater train's performance on the product TVP, are also studied. Based on the scenarios analyzed, it can be concluded that the actual water volume (kbbl/day) has greater impact on the heat exchanger's duty; thus, incoming free water to Terengganu Crude Oil Terminal should be less than 19.5 kbbl/day (9.1 vol%) at the normal incoming crude oil flow rate of 195 (kbbl/day).

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.

Nowadays, computers are extensively used in engineering modeling and simulation fields in many different ways, one of which is in chemical engineering. Simulation and modeling of a chemical process plant and the sizing of the equipment with the assistance of computers, is of special interests to process engineers and investors. This is due to the ability of high speed computers, which make millions of mathematical calculations in less than a second associated with the new powerful software that make the engineering calculations more reliable and precise by making very fast iterations in thermodynamics, heat and mass transfer calculations. This combination of new technological hardware and developed software enables process engineers to deal with simulation, design, optimization, control, analysis etc. of complex plants, e.g. refinery and petrochemical plants, reliably and satisfactorily. The main chemical process simulators used for static and dynamic simulations are ASPEN PLUS, ASPEN HYSYS, PRO II, and CHEMCAD. The basic design concepts of all simulators are the same and one can fairly use all simulators if one is expert in any of them. Hydrogenation process is an example of the complex plants, to which a special attention is made by process designers and manufacturers. This process is used for upgrading of hydrocarbon feeds containing sulfur, nitrogen and/or other unsaturated hydrocarbon compounds. In oil and gas refineries, the product of steam cracking cuts, which is valuable, may be contaminated by these unwanted components and thus there is a need to remove those pollutants in downstream of the process. Hydrogenation is also used to increase the octane number of gasoline and gas oil. Sulfur, nitrogen and oxygen compounds and other unsaturated hydrocarbons are undesired components causing environmental issues, production of by-products, poisoning the catalysts and corrosion of the equipment. The unsaturated C=C double bonds in dioleffinic and alkenyl aromatics compounds, on the other hand, cause unwanted polymerization reactions due to having the functionality equal to or greater than 2. Hydrogenation process of the undesired components will remove those impurities and/or increase the octane number of aforementioned hydrocarbons. This process is sometimes referred to as “hydrotreating”; however, “upgrader” is a general word and is, of course, of more interest. In this thesis, a hydrogenation process plant was designed on the basis of the chemistry of hydrocarbons, hydrogenation reaction mechanism, detailed study of thermodynamics and kinetics and then a steady-state simulation and design of the process is carried out by ASPEN HYSYS 2006 followed by design evaluation and some modifications and conclusions. Hydrogenation reaction has a complicated mechanism. It has been subjected to hot and controversial debates over decades. Many kinetic data are available, which contradict one another. Among them, some of the experimental researches utilize good assumptions in order to simplify the mechanism so that a “Kinetic Reaction” modeling can be employed. This thesis takes the benefit of such research works and applies some conditions to approve the validity of those assumptions. On the basis of this detailed study of reaction modeling and kinetic data, a hydrogenation plant was designed to produce and purify over 98 million kilograms of different products; e.g. Benzene, Toluene, Iso-octane etc. with fairly high purity.

Nowadays, computers are extensively used in engineering modeling and simulation fields in many different ways, one of which is in chemical engineering. Simulation and modeling of a chemical process plant and the sizing of the equipment with the assistance of computers, is of special interests to process engineers and investors. This is due to the ability of high speed computers, which make millions of mathematical calculations in less than a second associated with the new powerful software that make the engineering calculations more reliable and precise by making very fast iterations in thermodynamics, heat and mass transfer calculations. This combination of new technological hardware and developed software enables process engineers to deal with simulation, design, optimization, control, analysis etc. of complex plants, e.g. refinery and petrochemical plants, reliably and satisfactorily. The main chemical process simulators used for static and dynamic simulations are ASPEN PLUS, ASPEN HYSYS, PRO II, and CHEMCAD. The basic design concepts of all simulators are the same and one can fairly use all simulators if one is expert in any of them. Hydrogenation process is an example of the complex plants, to which a special attention is made by process designers and manufacturers. This process is used for upgrading of hydrocarbon feeds containing sulfur, nitrogen and/or other unsaturated hydrocarbon compounds. In oil and gas refineries, the product of steam cracking cuts, which is valuable, may be contaminated by these unwanted components and thus there is a need to remove those pollutants in downstream of the process. Hydrogenation is also used to increase the octane number of gasoline and gas oil. Sulfur, nitrogen and oxygen compounds and other unsaturated hydrocarbons are undesired components causing environmental issues, production of by-products, poisoning the catalysts and corrosion of the equipment. The unsaturated C=C double bonds in dioleffinic and alkenyl aromatics compounds, on the other hand, cause unwanted polymerization reactions due to having the functionality equal to or greater than 2. Hydrogenation process of the undesired components will remove those impurities and/or increase the octane number of aforementioned hydrocarbons. This process is sometimes referred to as “hydrotreating”; however, “upgrader” is a general word and is, of course, of more interest. In this thesis, a hydrogenation process plant was designed on the basis of the chemistry of hydrocarbons, hydrogenation reaction mechanism, detailed study of thermodynamics and kinetics and then a steady-state simulation and design of the process is carried out by ASPEN HYSYS 2006 followed by design evaluation and some modifications and conclusions. Hydrogenation reaction has a complicated mechanism. It has been subjected to hot and controversial debates over decades. Many kinetic data are available, which contradict one another. Among them, some of the experimental researches utilize good assumptions in order to simplify the mechanism so that a “Kinetic Reaction” modeling can be employed. This thesis takes the benefit of such research works and applies some conditions to approve the validity of those assumptions. On the basis of this detailed study of reaction modeling and kinetic data, a hydrogenation plant was designed to produce and purify over 98 million kilograms of different products; e.g. Benzene, Toluene, Iso-octane etc. with fairly high purity.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-02T22:55:04Z No. of bitstreams: 1 HerbertSenzanoLopes_DISSERT.pdf: 1964831 bytes, checksum: a1f3b710808bf3ed42490612f2700bca (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-04T00:31:31Z (GMT) No. of bitstreams: 1 HerbertSenzanoLopes_DISSERT.pdf: 1964831 bytes, checksum: a1f3b710808bf3ed42490612f2700bca (MD5) / Made available in DSpace on 2016-03-04T00:31:31Z (GMT). No. of bitstreams: 1 HerbertSenzanoLopes_DISSERT.pdf: 1964831 bytes, checksum: a1f3b710808bf3ed42490612f2700bca (MD5) Previous issue date: 2014-12-23 / A parte pesada do petr?leo pode ser utilizada para in?meras finalidades, uma delas ? a obten??o de ?leos lubrificantes. Com base nesse contexto, muitos pesquisadores v?m estudando alternativas de separa??o desses constituintes de petr?leo bruto, entre elas pode ser citada a destila??o molecular, uma t?cnica de evapora??o for?ada diferente dos outros processos convencionais presentes na literatura. Este processo pode ser classificado como um caso especial de destila??o a alto v?cuo com press?es que chegam a atingir faixas extremamente baixas da ordem de 0,1 Pascal. As superf?cies de evapora??o e de condensa??o devem apresentar uma dist?ncia entre si da ordem de grandeza do percurso livre m?dio das mol?culas evaporadas, isto ?, as mol?culas evaporadas facilmente atingir?o o condensador, pois as mesmas encontrar?o um percurso sem obst?culos, o que ? desej?vel. Logo, a principal contribui??o deste trabalho consiste na simula??o do processo de destila??o molecular de filme descendente do petr?leo. O petr?leo bruto foi caracterizado utilizando o UniSim? Design R430 e o Aspen HYSYS? V8.5. Com os resultados desta caracteriza??o foram efetuados, em planilhas de c?lculo no Microsoft? Excel?, os c?lculos das propriedades f?sico-qu?micas dos res?duos de uma amostra de petr?leo, i.e., termodin?micas e de transporte. De posse dessas propriedades estimadas e das condi??es de contorno sugeridas pela literatura, foram resolvidas as equa??es dos perfis de temperatura e concentra??o atrav?s do m?todo de diferen?as finitas impl?cito utilizando a linguagem de programa??o Visual Basic? (VBA) for Excel?. O resultado do perfil de temperatura apresentou-se coerente com os reproduzidos pela literatura, havendo em seus valores iniciais uma leve distor??o em consequ?ncia da natureza do ?leo estudado ser mais leve que o da literatura. Os resultados dos perfis de concentra??o mostraram-se eficientes permitindo perceber que as concentra??es dos mais vol?teis diminuem e as dos menos vol?teis aumentam em fun??o do comprimento do evaporador. De acordo com os fen?menos de transporte presentes no processo, o perfil de velocidade tende a aumentar at? um ponto m?ximo e em seguida diminui e a espessura do filme diminui, ambos em fun??o do comprimento do evaporador. Conclui-se que o c?digo de simula??o em linguagem Visual Basic? (VBA) ? um produto final do trabalho que permite aplica??o para a destila??o molecular do petr?leo e de outras misturas similares. / The heavy part of the oil can be used for numerous purposes, e.g. to obtain lubricating oils. In this context, many researchers have been studying alternatives such separation of crude oil components, among which may be mentioned molecular distillation. Molecular distillation is a forced evaporation technique different from other conventional processes in the literature. This process can be classified as a special distillation case under high vacuum with pressures that reach extremely low ranges of the order of 0.1 Pascal. The evaporation and condensation surfaces must have a distance from each other of the magnitude order of mean free path of the evaporated molecules, that is, molecules evaporated easily reach the condenser, because they find a route without obstacles, what is desirable. Thus, the main contribution of this work is the simulation of the falling-film molecular distillation for crude oil mixtures. The crude oil was characterized using UniSim? Design and R430 Aspen HYSYS? V8.5. The results of this characterization were performed in spreadsheets of Microsoft? Excel?, calculations of the physicochemical properties of the waste of an oil sample, i.e., thermodynamic and transport. Based on this estimated properties and boundary conditions suggested by the literature, equations of temperature and concentration profiles were resolved through the implicit finite difference method using the programming language Visual Basic? (VBA) for Excel?. The result of the temperature profile showed consistent with the reproduced by literature, having in their initial values a slight distortion as a result of the nature of the studied oil is lighter than the literature, since the results of the concentration profiles were effective allowing realize that the concentration of the more volatile decreases and of the less volatile increases due to the length of the evaporator. According to the transport phenomena present in the process, the velocity profile tends to increase to a peak and then decreases, and the film thickness decreases, both as a function of the evaporator length. It is concluded that the simulation code in Visual Basic? language (VBA) is a final product of the work that allows application to molecular distillation of petroleum and other similar mixtures.