The Experts below are selected from a list of 1755 Experts worldwide ranked by ideXlab platform
A S Wood - One of the best experts on this subject based on the ideXlab platform.
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improving fuel quality by whole crude oil hydrotreating a kinetic model for hydrodeasphaltenization in a Trickle Bed Reactor
Applied Energy, 2012Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Fossil fuel is still a predominant source of the global energy requirement. Hydrotreating of whole crude oil has the ability to increase the productivity of middle distillate fractions and improve the fuel quality by simultaneously reducing contaminants such as sulfur, nitrogen, vanadium, nickel and asphaltene to the levels required by the regulatory bodies. Hydrotreating is usually carried out in a Trickle Bed Reactor (TBR) where hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydrodemetallization (HDM) and hydrodeasphaltenization (HDAs) reactions take place simultaneously. To develop a detailed and a validated TBR process model which can be used for design and optimization of the hydrotreating process, it is essential to develop kinetic models for each of these reactions. Most recently, the authors have developed kinetic models for all of these chemical reactions except that of HDAs. In this work, a kinetic model (in terms of kinetic parameters) for the HDAs reaction in the TBR is developed.
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improving fuel quality by whole crude oil hydrotreating a kinetic model for hydrodeasphaltenization in a Trickle Bed Reactor
Applied Energy, 2012Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Abstract Fossil fuel is still a predominant source of the global energy requirement. Hydrotreating of whole crude oil has the ability to increase the productivity of middle distillate fractions and improve the fuel quality by simultaneously reducing contaminants such as sulfur, nitrogen, vanadium, nickel and asphaltene to the levels required by the regulatory bodies. Hydrotreating is usually carried out in a Trickle Bed Reactor (TBR) where hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydrodemetallization (HDM) and hydrodeasphaltenization (HDAs) reactions take place simultaneously. To develop a detailed and a validated TBR process model which can be used for design and optimization of the hydrotreating process, it is essential to develop kinetic models for each of these reactions. Most recently, the authors have developed kinetic models for all of these chemical reactions except that of HDAs. In this work, a kinetic model (in terms of kinetic parameters) for the HDAs reaction in the TBR is developed. A three phase TBR process model incorporating the HDAs reactions with unknown kinetic parameters is developed. Also, a series of experiments has been conducted in an isothermal TBR under different operating conditions affecting the removal of asphaltene. The unknown kinetic parameters are then obtained by applying a parameter estimation technique based on minimization of the sum of square errors ( SSEs ) between the experimental and predicted concentrations of asphaltene compound in the crude oil. The full model with the estimated kinetic parameters is then applied to evaluate the removal of asphaltene (thus affecting fuel quality) under different operating conditions (than those used in experiments).
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kinetic model development and simulation of simultaneous hydrodenitrogenation and hydrodemetallization of crude oil in Trickle Bed Reactor
Fuel, 2011Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Abstract One of the more difficult tasks in the petroleum refining industries that have not been considered largely in the literature is hydrotreating (HDT) of crude oil. The accurate calculations of kinetic models of the relevant reaction scheme are required for obtaining helpful models for HDT reactions, which can be confidently used for Reactor design, operating and control. In this work, an optimization technique is employed to evaluate the best kinetic models of a Trickle Bed Reactor (TBR) process utilized for hydrodenitrogenation (HDN) and hydrodemetallization (HDM) that includes hydrodevanadization (HDV) and hydrodenickelation (HDNi) of crude oil based on pilot plant experiments. The minimization of the sum of the squared errors (SSE) between the experimental and estimated concentrations of nitrogen (N), vanadium (V) and nickel (Ni) compounds in the products is used as an objective function in the optimization problem to determine the kinetic parameters. A series of experimental work was conducted in a continuous flow isothermal Trickle Bed Reactor, using crude oil as a feedstock and the commercial cobalt–molybdenum on alumina (Co–Mo/γ-Al2O3) as a catalyst. A three-phase heterogeneous model based on two–film theory is developed to describe the behaviour of crude oil hydroprocessing in a pilot–plant Trickle Bed Reactor (TBR) system. The hydroprocessing reactions have been modelled by power law kinetics with respect to nitrogen, vanadium and nickel compounds, and with respect to hydrogen. In this work, the gPROMS (general PROcess Modelling System) package has been used for modelling, simulation and parameter estimation via optimization. The model simulations results were found to agree well with the experiments carried out in a wide range of the studied operating conditions. The model is employed to predict the concentration profiles of hydrogen, nitrogen, vanadium and nickel along the catalyst Bed length in three phases.
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kinetic parameter estimation and simulation of Trickle Bed Reactor for hydrodesulfurization of crude oil
Chemical Engineering Science, 2011Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Abstract Hydrodesulfurization (HDS) of crude oil has not been reported widely in the literature and it is one of the most challenging tasks in the petroleum refining industry. In order to obtain useful models for HDS process that can be confidently applied to Reactor design, operation and control, the accurate estimation of kinetic parameters of the relevant reaction scheme are required. In this work, an optimization technique is used in order to obtain the best values of kinetic parameters in Trickle-Bed Reactor (TBR) process used for hydrodesulfurization (HDS) of crude oil based on pilot plant experiment. The optimization technique is based on minimization of the sum of the square errors (SSE) between the experimental and predicted concentrations of sulfur compound in the products using two approaches (linear (LN) and non-linear (NLN) regressions). A set of experiments were carried out in a continuous flow isothermal Trickle-Bed Reactor using crude oil as a feedstock and the commercial cobalt–molybdenum on alumina (Co–Mo/γ-Al 2 O 3 ) as a catalyst. The Reactor temperature was varied from 335 to 400 °C, the hydrogen pressure from 4 to 10 MPa and the liquid hourly space velocity (LHSV) from 0.5 to 1.5 h −1 , keeping constant hydrogen to oil ratio (H 2 /oil) at 250 L/L. A steady-state heterogeneous model is developed based on two-film theory, which includes mass transfer phenomena in addition to many correlations for estimating physiochemical properties of the compounds. The hydrodesulfurization reaction is descriBed by Langmuir–Hinshelwood kinetics. gPROMS software is employed for modelling, parameter estimation and simulation of hydrodesulfurization of crude oil in this work. The model simulations results were found to agree well with the experiments carried out in a wide range of the studied operating conditions. Following the parameter estimation, the model is used to predict the concentration profiles of hydrogen, hydrogen sulfide and sulfur along the catalyst Bed length in gas, liquid and solid phase, which provides further insight of the process.
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improvement of the middle distillate yields during crude oil hydrotreatment in a Trickle Bed Reactor
Energy & Fuels, 2011Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:The growing demand for high-quality middle distillates is increasing worldwide, whereas the demand for low-value oil products, such as heavy oils and residues, is decreasing. Thus, maximizing the production of more liquid distillates of very high quality is of immediate interest to refiners. At the same time, environmental legislation has led to more strict specifications of petroleum derivatives. Hydrotreatment (HDT) of crude oil is one of the most challenging tasks in the petroleum refining industry, which has not been reported widely in the literature. In this work, crude oil was hydrotreated upon a commercial cobalt−molybdenum on alumina (Co−Mo/γ-Al2O3) catalyst presulfided at specified conditions. Detailed pilot-plant experiments were conducted in a continuous-flow isothermal Trickle-Bed Reactor (TBR), and the main hydrotreating reactions were hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydrodeasphaltenization (HDAs), and hydrodemetallization (HDM), which includes hydrodevanadization (HDV...
Aysar T Jarullah - One of the best experts on this subject based on the ideXlab platform.
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Optimal Design of a Trickle Bed Reactor for Light Fuel Oxidative Desulfurization Based on Experiments and Modeling
Energy & Fuels, 2015Co-Authors: Amer T. Nawaf, Aysar T Jarullah, Saba A. Gheni, Iqbal M MujtabaAbstract:In this work, the performance of oxidative desulfurization (ODS) of dibenzothiophene (DBT) in light gas oil (LGO) is evaluated with a homemade manganese oxide (MnO2/γ-Al2O3) catalyst. The catalyst is prepared by the incipient wetness impregnation (IWI) method with air under moderate operating conditions. The effect of different reaction parameters such as reaction temperature, liquid hour space velocity, and initial concentration of DBT is also investigated experimentally. For developing a detailed and validated Trickle Bed Reactor (TBR) process model that can be employed for design and optimization of the ODS process, it is important to develop kinetic models for the relevant reactions with high accuracy. The best kinetic model for the ODS process taking into account hydrodynamic factors (mainly, catalyst effectiveness factor, catalyst wetting efficiency, and internal diffusion) and the physical properties affecting the oxidation process is developed utilizing data from pilot plant experiments. An optimi...
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improving fuel quality by whole crude oil hydrotreating a kinetic model for hydrodeasphaltenization in a Trickle Bed Reactor
Applied Energy, 2012Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Fossil fuel is still a predominant source of the global energy requirement. Hydrotreating of whole crude oil has the ability to increase the productivity of middle distillate fractions and improve the fuel quality by simultaneously reducing contaminants such as sulfur, nitrogen, vanadium, nickel and asphaltene to the levels required by the regulatory bodies. Hydrotreating is usually carried out in a Trickle Bed Reactor (TBR) where hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydrodemetallization (HDM) and hydrodeasphaltenization (HDAs) reactions take place simultaneously. To develop a detailed and a validated TBR process model which can be used for design and optimization of the hydrotreating process, it is essential to develop kinetic models for each of these reactions. Most recently, the authors have developed kinetic models for all of these chemical reactions except that of HDAs. In this work, a kinetic model (in terms of kinetic parameters) for the HDAs reaction in the TBR is developed.
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improving fuel quality by whole crude oil hydrotreating a kinetic model for hydrodeasphaltenization in a Trickle Bed Reactor
Applied Energy, 2012Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Abstract Fossil fuel is still a predominant source of the global energy requirement. Hydrotreating of whole crude oil has the ability to increase the productivity of middle distillate fractions and improve the fuel quality by simultaneously reducing contaminants such as sulfur, nitrogen, vanadium, nickel and asphaltene to the levels required by the regulatory bodies. Hydrotreating is usually carried out in a Trickle Bed Reactor (TBR) where hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydrodemetallization (HDM) and hydrodeasphaltenization (HDAs) reactions take place simultaneously. To develop a detailed and a validated TBR process model which can be used for design and optimization of the hydrotreating process, it is essential to develop kinetic models for each of these reactions. Most recently, the authors have developed kinetic models for all of these chemical reactions except that of HDAs. In this work, a kinetic model (in terms of kinetic parameters) for the HDAs reaction in the TBR is developed. A three phase TBR process model incorporating the HDAs reactions with unknown kinetic parameters is developed. Also, a series of experiments has been conducted in an isothermal TBR under different operating conditions affecting the removal of asphaltene. The unknown kinetic parameters are then obtained by applying a parameter estimation technique based on minimization of the sum of square errors ( SSEs ) between the experimental and predicted concentrations of asphaltene compound in the crude oil. The full model with the estimated kinetic parameters is then applied to evaluate the removal of asphaltene (thus affecting fuel quality) under different operating conditions (than those used in experiments).
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kinetic model development and simulation of simultaneous hydrodenitrogenation and hydrodemetallization of crude oil in Trickle Bed Reactor
Fuel, 2011Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Abstract One of the more difficult tasks in the petroleum refining industries that have not been considered largely in the literature is hydrotreating (HDT) of crude oil. The accurate calculations of kinetic models of the relevant reaction scheme are required for obtaining helpful models for HDT reactions, which can be confidently used for Reactor design, operating and control. In this work, an optimization technique is employed to evaluate the best kinetic models of a Trickle Bed Reactor (TBR) process utilized for hydrodenitrogenation (HDN) and hydrodemetallization (HDM) that includes hydrodevanadization (HDV) and hydrodenickelation (HDNi) of crude oil based on pilot plant experiments. The minimization of the sum of the squared errors (SSE) between the experimental and estimated concentrations of nitrogen (N), vanadium (V) and nickel (Ni) compounds in the products is used as an objective function in the optimization problem to determine the kinetic parameters. A series of experimental work was conducted in a continuous flow isothermal Trickle Bed Reactor, using crude oil as a feedstock and the commercial cobalt–molybdenum on alumina (Co–Mo/γ-Al2O3) as a catalyst. A three-phase heterogeneous model based on two–film theory is developed to describe the behaviour of crude oil hydroprocessing in a pilot–plant Trickle Bed Reactor (TBR) system. The hydroprocessing reactions have been modelled by power law kinetics with respect to nitrogen, vanadium and nickel compounds, and with respect to hydrogen. In this work, the gPROMS (general PROcess Modelling System) package has been used for modelling, simulation and parameter estimation via optimization. The model simulations results were found to agree well with the experiments carried out in a wide range of the studied operating conditions. The model is employed to predict the concentration profiles of hydrogen, nitrogen, vanadium and nickel along the catalyst Bed length in three phases.
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kinetic parameter estimation and simulation of Trickle Bed Reactor for hydrodesulfurization of crude oil
Chemical Engineering Science, 2011Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Abstract Hydrodesulfurization (HDS) of crude oil has not been reported widely in the literature and it is one of the most challenging tasks in the petroleum refining industry. In order to obtain useful models for HDS process that can be confidently applied to Reactor design, operation and control, the accurate estimation of kinetic parameters of the relevant reaction scheme are required. In this work, an optimization technique is used in order to obtain the best values of kinetic parameters in Trickle-Bed Reactor (TBR) process used for hydrodesulfurization (HDS) of crude oil based on pilot plant experiment. The optimization technique is based on minimization of the sum of the square errors (SSE) between the experimental and predicted concentrations of sulfur compound in the products using two approaches (linear (LN) and non-linear (NLN) regressions). A set of experiments were carried out in a continuous flow isothermal Trickle-Bed Reactor using crude oil as a feedstock and the commercial cobalt–molybdenum on alumina (Co–Mo/γ-Al 2 O 3 ) as a catalyst. The Reactor temperature was varied from 335 to 400 °C, the hydrogen pressure from 4 to 10 MPa and the liquid hourly space velocity (LHSV) from 0.5 to 1.5 h −1 , keeping constant hydrogen to oil ratio (H 2 /oil) at 250 L/L. A steady-state heterogeneous model is developed based on two-film theory, which includes mass transfer phenomena in addition to many correlations for estimating physiochemical properties of the compounds. The hydrodesulfurization reaction is descriBed by Langmuir–Hinshelwood kinetics. gPROMS software is employed for modelling, parameter estimation and simulation of hydrodesulfurization of crude oil in this work. The model simulations results were found to agree well with the experiments carried out in a wide range of the studied operating conditions. Following the parameter estimation, the model is used to predict the concentration profiles of hydrogen, hydrogen sulfide and sulfur along the catalyst Bed length in gas, liquid and solid phase, which provides further insight of the process.
Konrad Koch - One of the best experts on this subject based on the ideXlab platform.
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load change capability of an anaerobic thermophilic Trickle Bed Reactor for dynamic h2 co2 biomethanation
Bioresource Technology, 2019Co-Authors: Dietmar Strübing, Michael Lebuhn, Jorg E Drewes, Andreas B Moeller, B Mosnang, Konrad KochAbstract:Abstract Increasing shares of energy production originating from fluctuating renewable sources require measures that are able to balance power production for a stable electricity grid. H 2 /CO 2 biomethanation is a suitable approach to convert fluctuating excess renewable energy into the storable substitute natural gas. This study investigated the rapid load change capability of an anaerobic thermophilic Trickle Bed Reactor while maintaining a high methane content. The return to full load (62.1 m 3 H2 /m 3 Trickle Bed /d) after a 30-min operational off-cycle was possible almost immediately, while 24-h interruptions required a 60-min stepwise load increase. To accelerate this delayed microbial conversion activity, non-steady state substrate gas conversion can be controlled via substrate and product gas flow rates, allowing to reactivate the entire microbial community and produce high quality product gas. Reactor design might be further improved to avoid short-circuiting and use the entire Trickle Bed gas phase as high quality gas buffer during initial load increases.
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anaerobic thermophilic Trickle Bed Reactor as a promising technology for flexible and demand oriented h2 co2 biomethanation
Applied Energy, 2018Co-Authors: Dietmar Strübing, Michael Lebuhn, Jorg E Drewes, Andreas B Moeller, B Mosnang, Konrad KochAbstract:Abstract Increasing energy production from variable renewable sources, especially wind and solar photovoltaic, requires measures to maintain a stable electricity grid that balances power production and demand. Flexible conversion of excess renewable energy into a storable substitute natural gas via H2/CO2 biomethanation may be a suitable approach for tackling this challenge. This study investigated the performance of an anaerobic thermophilic Trickle Bed Reactor (ATTBR) during demand-oriented H2/CO2 biomethanation. Different combinations of standby periods (SPs) varying from 1 to 8 days and standby temperatures (25 °C and 55 °C) as well as their repetitive effect on the biological gas conversion performance were systematically evaluated using a standardized restart procedure. The results revealed that the influence of the SP temperature on the restart performance by far outweighed the length of SP investigated. While the investigated ATTBR represents a robust system with a very good restart performance after 25 °C SPs, the repetitive effect of 55 °C SPs was in particular identified as a critical standby setting that causes deterioration of the restart performance. This may be attributed to increased inactivation rates for thermophilic hydrogenotrophic methanogens at 55 °C, which also influences volatile fatty acid transformation dynamics and leads to substantial propionate accumulation (∼3000 mg/L) during 55 °C SPs. For the application of ATTBR in dynamic energy conversion and storage scenarios, further research is required to reduce response times and enhance flexibility.
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High performance biological methanation in a thermophilic anaerobic Trickle Bed Reactor
Bioresource Technology, 2017Co-Authors: Dietmar Strübing, Bettina Huber, Michael Lebuhn, Jorg E Drewes, Konrad KochAbstract:In order to enhance energy efficiency of biological methanation of CO2and H2, this study investigated the performance of a thermophilic (55 °C) anaerobic Trickle Bed Reactor (ATBR) (58.1 L) at ambient pressure. With a methane production rate of up to 15.4 m3CH4/(m3Trickle Bed·d) at methane concentrations above 98%, the ATBR can easily compete with the performance of other mixed culture methanation Reactors. Control of pH and nutrient supply turned out to be crucial for stable operation and was affected significantly by dilution due to metabolic water production, especially during demand-orientated operation. Considering practical applications, inoculation with digested sludge, containing a diverse biocenosis, showed high adaptive capacity due to intrinsic biological diversity. However, no macroscopic biofilm formation was observed at thermophilic conditions even after 313 days of operation. The applied approach illustrates the high potential of thermophilic ATBRs as a very efficient energy conversion and storage technology.
Iqbal M Mujtaba - One of the best experts on this subject based on the ideXlab platform.
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Optimal Design of a Trickle Bed Reactor for Light Fuel Oxidative Desulfurization Based on Experiments and Modeling
Energy & Fuels, 2015Co-Authors: Amer T. Nawaf, Aysar T Jarullah, Saba A. Gheni, Iqbal M MujtabaAbstract:In this work, the performance of oxidative desulfurization (ODS) of dibenzothiophene (DBT) in light gas oil (LGO) is evaluated with a homemade manganese oxide (MnO2/γ-Al2O3) catalyst. The catalyst is prepared by the incipient wetness impregnation (IWI) method with air under moderate operating conditions. The effect of different reaction parameters such as reaction temperature, liquid hour space velocity, and initial concentration of DBT is also investigated experimentally. For developing a detailed and validated Trickle Bed Reactor (TBR) process model that can be employed for design and optimization of the ODS process, it is important to develop kinetic models for the relevant reactions with high accuracy. The best kinetic model for the ODS process taking into account hydrodynamic factors (mainly, catalyst effectiveness factor, catalyst wetting efficiency, and internal diffusion) and the physical properties affecting the oxidation process is developed utilizing data from pilot plant experiments. An optimi...
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improving fuel quality by whole crude oil hydrotreating a kinetic model for hydrodeasphaltenization in a Trickle Bed Reactor
Applied Energy, 2012Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Fossil fuel is still a predominant source of the global energy requirement. Hydrotreating of whole crude oil has the ability to increase the productivity of middle distillate fractions and improve the fuel quality by simultaneously reducing contaminants such as sulfur, nitrogen, vanadium, nickel and asphaltene to the levels required by the regulatory bodies. Hydrotreating is usually carried out in a Trickle Bed Reactor (TBR) where hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydrodemetallization (HDM) and hydrodeasphaltenization (HDAs) reactions take place simultaneously. To develop a detailed and a validated TBR process model which can be used for design and optimization of the hydrotreating process, it is essential to develop kinetic models for each of these reactions. Most recently, the authors have developed kinetic models for all of these chemical reactions except that of HDAs. In this work, a kinetic model (in terms of kinetic parameters) for the HDAs reaction in the TBR is developed.
-
improving fuel quality by whole crude oil hydrotreating a kinetic model for hydrodeasphaltenization in a Trickle Bed Reactor
Applied Energy, 2012Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Abstract Fossil fuel is still a predominant source of the global energy requirement. Hydrotreating of whole crude oil has the ability to increase the productivity of middle distillate fractions and improve the fuel quality by simultaneously reducing contaminants such as sulfur, nitrogen, vanadium, nickel and asphaltene to the levels required by the regulatory bodies. Hydrotreating is usually carried out in a Trickle Bed Reactor (TBR) where hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydrodemetallization (HDM) and hydrodeasphaltenization (HDAs) reactions take place simultaneously. To develop a detailed and a validated TBR process model which can be used for design and optimization of the hydrotreating process, it is essential to develop kinetic models for each of these reactions. Most recently, the authors have developed kinetic models for all of these chemical reactions except that of HDAs. In this work, a kinetic model (in terms of kinetic parameters) for the HDAs reaction in the TBR is developed. A three phase TBR process model incorporating the HDAs reactions with unknown kinetic parameters is developed. Also, a series of experiments has been conducted in an isothermal TBR under different operating conditions affecting the removal of asphaltene. The unknown kinetic parameters are then obtained by applying a parameter estimation technique based on minimization of the sum of square errors ( SSEs ) between the experimental and predicted concentrations of asphaltene compound in the crude oil. The full model with the estimated kinetic parameters is then applied to evaluate the removal of asphaltene (thus affecting fuel quality) under different operating conditions (than those used in experiments).
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kinetic model development and simulation of simultaneous hydrodenitrogenation and hydrodemetallization of crude oil in Trickle Bed Reactor
Fuel, 2011Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Abstract One of the more difficult tasks in the petroleum refining industries that have not been considered largely in the literature is hydrotreating (HDT) of crude oil. The accurate calculations of kinetic models of the relevant reaction scheme are required for obtaining helpful models for HDT reactions, which can be confidently used for Reactor design, operating and control. In this work, an optimization technique is employed to evaluate the best kinetic models of a Trickle Bed Reactor (TBR) process utilized for hydrodenitrogenation (HDN) and hydrodemetallization (HDM) that includes hydrodevanadization (HDV) and hydrodenickelation (HDNi) of crude oil based on pilot plant experiments. The minimization of the sum of the squared errors (SSE) between the experimental and estimated concentrations of nitrogen (N), vanadium (V) and nickel (Ni) compounds in the products is used as an objective function in the optimization problem to determine the kinetic parameters. A series of experimental work was conducted in a continuous flow isothermal Trickle Bed Reactor, using crude oil as a feedstock and the commercial cobalt–molybdenum on alumina (Co–Mo/γ-Al2O3) as a catalyst. A three-phase heterogeneous model based on two–film theory is developed to describe the behaviour of crude oil hydroprocessing in a pilot–plant Trickle Bed Reactor (TBR) system. The hydroprocessing reactions have been modelled by power law kinetics with respect to nitrogen, vanadium and nickel compounds, and with respect to hydrogen. In this work, the gPROMS (general PROcess Modelling System) package has been used for modelling, simulation and parameter estimation via optimization. The model simulations results were found to agree well with the experiments carried out in a wide range of the studied operating conditions. The model is employed to predict the concentration profiles of hydrogen, nitrogen, vanadium and nickel along the catalyst Bed length in three phases.
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kinetic parameter estimation and simulation of Trickle Bed Reactor for hydrodesulfurization of crude oil
Chemical Engineering Science, 2011Co-Authors: Aysar T Jarullah, Iqbal M Mujtaba, A S WoodAbstract:Abstract Hydrodesulfurization (HDS) of crude oil has not been reported widely in the literature and it is one of the most challenging tasks in the petroleum refining industry. In order to obtain useful models for HDS process that can be confidently applied to Reactor design, operation and control, the accurate estimation of kinetic parameters of the relevant reaction scheme are required. In this work, an optimization technique is used in order to obtain the best values of kinetic parameters in Trickle-Bed Reactor (TBR) process used for hydrodesulfurization (HDS) of crude oil based on pilot plant experiment. The optimization technique is based on minimization of the sum of the square errors (SSE) between the experimental and predicted concentrations of sulfur compound in the products using two approaches (linear (LN) and non-linear (NLN) regressions). A set of experiments were carried out in a continuous flow isothermal Trickle-Bed Reactor using crude oil as a feedstock and the commercial cobalt–molybdenum on alumina (Co–Mo/γ-Al 2 O 3 ) as a catalyst. The Reactor temperature was varied from 335 to 400 °C, the hydrogen pressure from 4 to 10 MPa and the liquid hourly space velocity (LHSV) from 0.5 to 1.5 h −1 , keeping constant hydrogen to oil ratio (H 2 /oil) at 250 L/L. A steady-state heterogeneous model is developed based on two-film theory, which includes mass transfer phenomena in addition to many correlations for estimating physiochemical properties of the compounds. The hydrodesulfurization reaction is descriBed by Langmuir–Hinshelwood kinetics. gPROMS software is employed for modelling, parameter estimation and simulation of hydrodesulfurization of crude oil in this work. The model simulations results were found to agree well with the experiments carried out in a wide range of the studied operating conditions. Following the parameter estimation, the model is used to predict the concentration profiles of hydrogen, hydrogen sulfide and sulfur along the catalyst Bed length in gas, liquid and solid phase, which provides further insight of the process.
Dietmar Strübing - One of the best experts on this subject based on the ideXlab platform.
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load change capability of an anaerobic thermophilic Trickle Bed Reactor for dynamic h2 co2 biomethanation
Bioresource Technology, 2019Co-Authors: Dietmar Strübing, Michael Lebuhn, Jorg E Drewes, Andreas B Moeller, B Mosnang, Konrad KochAbstract:Abstract Increasing shares of energy production originating from fluctuating renewable sources require measures that are able to balance power production for a stable electricity grid. H 2 /CO 2 biomethanation is a suitable approach to convert fluctuating excess renewable energy into the storable substitute natural gas. This study investigated the rapid load change capability of an anaerobic thermophilic Trickle Bed Reactor while maintaining a high methane content. The return to full load (62.1 m 3 H2 /m 3 Trickle Bed /d) after a 30-min operational off-cycle was possible almost immediately, while 24-h interruptions required a 60-min stepwise load increase. To accelerate this delayed microbial conversion activity, non-steady state substrate gas conversion can be controlled via substrate and product gas flow rates, allowing to reactivate the entire microbial community and produce high quality product gas. Reactor design might be further improved to avoid short-circuiting and use the entire Trickle Bed gas phase as high quality gas buffer during initial load increases.
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anaerobic thermophilic Trickle Bed Reactor as a promising technology for flexible and demand oriented h2 co2 biomethanation
Applied Energy, 2018Co-Authors: Dietmar Strübing, Michael Lebuhn, Jorg E Drewes, Andreas B Moeller, B Mosnang, Konrad KochAbstract:Abstract Increasing energy production from variable renewable sources, especially wind and solar photovoltaic, requires measures to maintain a stable electricity grid that balances power production and demand. Flexible conversion of excess renewable energy into a storable substitute natural gas via H2/CO2 biomethanation may be a suitable approach for tackling this challenge. This study investigated the performance of an anaerobic thermophilic Trickle Bed Reactor (ATTBR) during demand-oriented H2/CO2 biomethanation. Different combinations of standby periods (SPs) varying from 1 to 8 days and standby temperatures (25 °C and 55 °C) as well as their repetitive effect on the biological gas conversion performance were systematically evaluated using a standardized restart procedure. The results revealed that the influence of the SP temperature on the restart performance by far outweighed the length of SP investigated. While the investigated ATTBR represents a robust system with a very good restart performance after 25 °C SPs, the repetitive effect of 55 °C SPs was in particular identified as a critical standby setting that causes deterioration of the restart performance. This may be attributed to increased inactivation rates for thermophilic hydrogenotrophic methanogens at 55 °C, which also influences volatile fatty acid transformation dynamics and leads to substantial propionate accumulation (∼3000 mg/L) during 55 °C SPs. For the application of ATTBR in dynamic energy conversion and storage scenarios, further research is required to reduce response times and enhance flexibility.
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High performance biological methanation in a thermophilic anaerobic Trickle Bed Reactor
Bioresource Technology, 2017Co-Authors: Dietmar Strübing, Bettina Huber, Michael Lebuhn, Jorg E Drewes, Konrad KochAbstract:In order to enhance energy efficiency of biological methanation of CO2and H2, this study investigated the performance of a thermophilic (55 °C) anaerobic Trickle Bed Reactor (ATBR) (58.1 L) at ambient pressure. With a methane production rate of up to 15.4 m3CH4/(m3Trickle Bed·d) at methane concentrations above 98%, the ATBR can easily compete with the performance of other mixed culture methanation Reactors. Control of pH and nutrient supply turned out to be crucial for stable operation and was affected significantly by dilution due to metabolic water production, especially during demand-orientated operation. Considering practical applications, inoculation with digested sludge, containing a diverse biocenosis, showed high adaptive capacity due to intrinsic biological diversity. However, no macroscopic biofilm formation was observed at thermophilic conditions even after 313 days of operation. The applied approach illustrates the high potential of thermophilic ATBRs as a very efficient energy conversion and storage technology.
