Oil and gas pipelines play a key role in the safe and efficient delivery of energy resources arou... more Oil and gas pipelines play a key role in the safe and efficient delivery of energy resources around the world. Crude oil by itself is not corrosive, but oil extracted from geological reservoirs is accompanied by varying amounts of water and acidic gases such as carbon dioxide (CO 2), which can form a corrosive combination. Estimating the corrosion rate and depth in pipelines is essential for predicting their failure probability. In the present study, a Bayesian network has been developed for predicting the distribution of corrosion rate in oil pipelines given the point estimates generated using an empirical corrosion simulation model. For this purpose, the simulation model considers corrosion parameters such as pipe diameter, flow temperature, flow velocity, and CO 2 partial pressure, among others. With the corrosion rate distribution predicted by the Bayesian network, corrosion depth-rate relationships have been employed to convert the corrosion rate distribution into failure probability distribution.
Biomimetic and Bioinspired Membranes for New Frontiers in Sustainable Water Treatment Technology, Dec 6, 2017
Polymeric RO membranes have dominated commercial applications since the very first RO desalinatio... more Polymeric RO membranes have dominated commercial applications since the very first RO desalination plant became industrially active. Due to their technological development they offer low-cost fabrication, ease of handling, and improved performance in selectivity and permeability. One of the earliest reviews on polymeric RO membrane materials was reported by Cadotte. It focused on composite RO membranes and covered the period from the inception of composite RO membranes up to approximately 1985. In 1993 Petersen offered a comprehensive review of the same subject, specifically examining the chemistry of the membrane materials. This section will briefly highlight the early development of membrane chemistry and graphical illustrations are used to visualize the performance improvement potential in RO membranes. This chronological description provides the readers with a quick overview of RO membranes formed by different mechanisms and their respective impact on the desalination industry over the years. For a more complete study of the early RO membrane development, readers are advised to further refer to Petersen's work. In general, the development of membrane materials can be divided into two periods according to research activity: (i) the search for a suitable materials (chemical composition) and membrane formation mechanisms (1960s to late 1980s), and (ii) the evolution of more controlled conditions for membrane formulation as a way of enhancing membrane functionality and durability (late 1980s to date).
Biomimetic and Bioinspired Membranes for New Frontiers in Sustainable Water Treatment Technology, Dec 6, 2017
Since the initial operation of the first reverse osmosis (RO) desalination plants, only polymeric... more Since the initial operation of the first reverse osmosis (RO) desalination plants, only polymeric membranes have been employed for industrial use. As described in the previous chapter, the various advancements in the conventional polymeric RO membranes have been rather limited since the late 1990s, especially in the membrane permeability issue. Although new membrane modules have been released, however most of them are improved through a method that relies on increasing the membrane area per module. Recently, advances in nanotechnology have led to the development of nanostructured materials which may form the basis for new RO membranes. Li and Wang have included inorganic membranes and thin film nanocomposite membranes in a recent review, whereas Mauter and Elimelech have discussed the potential of carbon nanotube membranes for use as high flux membrane filters. In this chapter, the development of membranes that have been discussed in the previous two reviews will be briefly highlighted with a particular focus on the possibility of them being engineered into commercial RO membranes. At the same time this chapter includes a discussion about structured polymeric membranes synthesized via a new course featuring carbon-derived nanoporous membranes and biomimetic membranes. The coverage of all proposed novel desalination RO membranes in this section is aimed to provide a general overview of these materials and to draw a fair comparison of them possibly being developed into commercial RO membranes.
A thermodynamic equilibrium analysis of hydrogen (H2) production from supercritical water gasific... more A thermodynamic equilibrium analysis of hydrogen (H2) production from supercritical water gasification (SCWG) of glucose was explored based on Gibbs free energy minimization using Soave–Redlich–Kwong equation of state with Boston Mathias alpha function (SRK-BM) property method. The effects of experimental conditions [i.e., glucose concentration (0.1–1.2 M), temperature (773–1073 K), and pressure (22–35 MPa)] on the equilibrium gas product yields and gasification performance were investigated. The temperature of about 923 K, pressure of 23–28 MPa, and glucose concentration being 0.1–0.2 M are justified to provide H2 yield in the order of its stoichiometric value (12 mol) with negligible amounts of CO and CH4. The simulated product yields, gasification efficiency (GE), cold gas efficiency (CGEP), cold gas efficiency of H2 (CGEH2), and calculated heat duty in this study were compared with their respective experimental data taken from the literature. The aforementioned operating conditions correspond to minimum heat duty of 60–107 MW and significant values of CGEP, CGEH2, and GE of 121.1–118.4, 118.4–105.4, and 158.3–151.6 %, respectively. The dissimilarity between the experimental product distributions reported in the literature is related to the reactor material and residence time as well as catalyst type. The current study provided thermodynamic parameters for optimizing the operational condition of glucose SCWG, which may be extended to other biomass supercritical water gasification systems.
Journal of Membrane and Separation Technology, 2013
The aim of the present study was to investigate the effects of operating conditions (transmembran... more The aim of the present study was to investigate the effects of operating conditions (transmembrane pressure, feed flow rate, and feed concentration) on the fouling attachment probabilities, mass of fouling, and cake height. Polycarbonate flat membrane with a pore size of 0.05 m was used under a constant feed flow rate and cross-flow mode in ultrafiltration of a latex paint solution. The results obtained indicate that increasing transmembrane pressure from 15 to 45 psi lead to an increase in the particle-to-particle (pp) and particle-to-membrane (pm) attachment probabilities from 0.4 to 0.76 and 0.55 to 0.8, respectively. It was observed that both attachment probabilities were significantly decreased when the feed flow rate was increased from 1 to 6 LPM (cross flow velocity from 10.4 to 62.5 cm/s). As a consequence, mass of fouling and cake height were reduced. Increasing the feed concentration from 0.78 to 1.82 kg/m 3 resulted in a substantial raise in the cake height from 4.3 to 18.5 m. Response Surface Methodology (RSM) was used to set up the experimental design. According to regression analysis, two correlation models were obtained in order to predict the fouling attachment probabilities at different operation conditions. Estimated attachment probabilities were used to predict mass of fouling retained by membrane.
The Canadian Journal of Chemical Engineering, 2009
The complex spectral refractive index (absorption index) of fly ash from two generating stations ... more The complex spectral refractive index (absorption index) of fly ash from two generating stations burning Canadian lignite and sub‐bituminous coals have been examined by two different techniques. Ash samples collected at different combustion conditions were analyzed. It is shown that the absorption index of both ashes is in the range of 0.004 to 0.018 in the wavelength range of 0.7‐2.5 μm. The effects of presence of carbonaceous material in ashes, iron content and different operating (combustion) conditions are reported.
An optimal design strategy of a network of fixed bed reactors for Methanol Production (MP) is pro... more An optimal design strategy of a network of fixed bed reactors for Methanol Production (MP) is proposed in this study. Both methanol production and profit spanning a production period of eight years have been set as objective functions to find the optimal production network. The conservation of mass and energy laws on a heterogeneous model of a single industrial methanol reactor was first developed. The model was solved numerically and was validated with industrial plant data. Different reactor network arrangements were then simulated in order to find an optimal superstructure. It was found that a structure of four reactors (two in series in parallel with another two in series) provide maximum production rate. The application of the more realistic objective function of profit showed that a configuration of two parallel reactors is the best configuration. This optimal structure produces 92 tons/day more methanol than a single reactor.
Coaxial mixers have been shown to be effective in enhancing the hydrodynamic stress and shear env... more Coaxial mixers have been shown to be effective in enhancing the hydrodynamic stress and shear environment inside the aerated systems. However, the scale-up study of the aerated coaxial mixing reactors based on a constant mass transfer coefficient has never been reported in the literature. In this study, for the first time, a practical technique is suggested to evaluate the scalability of these systems in terms of a constant mass transfer coefficient. The effects of impeller speed, impeller type, aeration rate, and pumping direction on the mass transfer, power consumption, gas holdup profile, fluid hydrodynamics, and energy dissipation rate were explored for gas dispersion in non-Newtonian fluids inside coaxial mixers through tomography, dynamic gassing-in, and computational fluid dynamics. It was found that a practical approach to preserve the mass transfer coefficient of the large-scale coaxial mixer the same as its small-scale counterpart was to maintain the volumetric aeration rate per working fluid volume constant.
Despite the wide applications of powder and solid mixing in industry, knowledge on the mixing of ... more Despite the wide applications of powder and solid mixing in industry, knowledge on the mixing of polydisperse solid particles in rotary drum blenders is lacking. This study investigates the mixing of monodisperse, bidisperse, tridisperse, and polydisperse solid particles in a rotary drum using the discrete element method. To validate the model developed in this study, experimental and simulation results were compared. The validated model was then employed to investigate the effects of the drum rotational speed, particle size, and initial loading method on the mixing quality. The degree of mixing of polydisperse particles was smaller than that for monodisperse particles owing to the segregation phenomenon. The mixing index increased from an initial value to a maximum and decreased slightly before reaching a plateau for bidisperse, tridisperse, and polydisperse particles as a direct result of the segregation of particles of different sizes. Final mixing indices were higher for polydisperse particles than for tridisperse and bidisperse particles. Additionally, segregation was weakened by introducing additional particles of intermediate size. The best mixing of bidisperse and tridisperse particles was achieved for top-bottom smaller-to-larger initial loading, while that of polydisperse systems was achieved using top-bottom smaller-to-larger and top-bottom larger-to-smaller initial loading methods.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Oil and gas pipelines play a key role in the safe and efficient delivery of energy resources arou... more Oil and gas pipelines play a key role in the safe and efficient delivery of energy resources around the world. Crude oil by itself is not corrosive, but oil extracted from geological reservoirs is accompanied by varying amounts of water and acidic gases such as carbon dioxide (CO 2), which can form a corrosive combination. Estimating the corrosion rate and depth in pipelines is essential for predicting their failure probability. In the present study, a Bayesian network has been developed for predicting the distribution of corrosion rate in oil pipelines given the point estimates generated using an empirical corrosion simulation model. For this purpose, the simulation model considers corrosion parameters such as pipe diameter, flow temperature, flow velocity, and CO 2 partial pressure, among others. With the corrosion rate distribution predicted by the Bayesian network, corrosion depth-rate relationships have been employed to convert the corrosion rate distribution into failure probability distribution.
Biomimetic and Bioinspired Membranes for New Frontiers in Sustainable Water Treatment Technology, Dec 6, 2017
Polymeric RO membranes have dominated commercial applications since the very first RO desalinatio... more Polymeric RO membranes have dominated commercial applications since the very first RO desalination plant became industrially active. Due to their technological development they offer low-cost fabrication, ease of handling, and improved performance in selectivity and permeability. One of the earliest reviews on polymeric RO membrane materials was reported by Cadotte. It focused on composite RO membranes and covered the period from the inception of composite RO membranes up to approximately 1985. In 1993 Petersen offered a comprehensive review of the same subject, specifically examining the chemistry of the membrane materials. This section will briefly highlight the early development of membrane chemistry and graphical illustrations are used to visualize the performance improvement potential in RO membranes. This chronological description provides the readers with a quick overview of RO membranes formed by different mechanisms and their respective impact on the desalination industry over the years. For a more complete study of the early RO membrane development, readers are advised to further refer to Petersen's work. In general, the development of membrane materials can be divided into two periods according to research activity: (i) the search for a suitable materials (chemical composition) and membrane formation mechanisms (1960s to late 1980s), and (ii) the evolution of more controlled conditions for membrane formulation as a way of enhancing membrane functionality and durability (late 1980s to date).
Biomimetic and Bioinspired Membranes for New Frontiers in Sustainable Water Treatment Technology, Dec 6, 2017
Since the initial operation of the first reverse osmosis (RO) desalination plants, only polymeric... more Since the initial operation of the first reverse osmosis (RO) desalination plants, only polymeric membranes have been employed for industrial use. As described in the previous chapter, the various advancements in the conventional polymeric RO membranes have been rather limited since the late 1990s, especially in the membrane permeability issue. Although new membrane modules have been released, however most of them are improved through a method that relies on increasing the membrane area per module. Recently, advances in nanotechnology have led to the development of nanostructured materials which may form the basis for new RO membranes. Li and Wang have included inorganic membranes and thin film nanocomposite membranes in a recent review, whereas Mauter and Elimelech have discussed the potential of carbon nanotube membranes for use as high flux membrane filters. In this chapter, the development of membranes that have been discussed in the previous two reviews will be briefly highlighted with a particular focus on the possibility of them being engineered into commercial RO membranes. At the same time this chapter includes a discussion about structured polymeric membranes synthesized via a new course featuring carbon-derived nanoporous membranes and biomimetic membranes. The coverage of all proposed novel desalination RO membranes in this section is aimed to provide a general overview of these materials and to draw a fair comparison of them possibly being developed into commercial RO membranes.
A thermodynamic equilibrium analysis of hydrogen (H2) production from supercritical water gasific... more A thermodynamic equilibrium analysis of hydrogen (H2) production from supercritical water gasification (SCWG) of glucose was explored based on Gibbs free energy minimization using Soave–Redlich–Kwong equation of state with Boston Mathias alpha function (SRK-BM) property method. The effects of experimental conditions [i.e., glucose concentration (0.1–1.2 M), temperature (773–1073 K), and pressure (22–35 MPa)] on the equilibrium gas product yields and gasification performance were investigated. The temperature of about 923 K, pressure of 23–28 MPa, and glucose concentration being 0.1–0.2 M are justified to provide H2 yield in the order of its stoichiometric value (12 mol) with negligible amounts of CO and CH4. The simulated product yields, gasification efficiency (GE), cold gas efficiency (CGEP), cold gas efficiency of H2 (CGEH2), and calculated heat duty in this study were compared with their respective experimental data taken from the literature. The aforementioned operating conditions correspond to minimum heat duty of 60–107 MW and significant values of CGEP, CGEH2, and GE of 121.1–118.4, 118.4–105.4, and 158.3–151.6 %, respectively. The dissimilarity between the experimental product distributions reported in the literature is related to the reactor material and residence time as well as catalyst type. The current study provided thermodynamic parameters for optimizing the operational condition of glucose SCWG, which may be extended to other biomass supercritical water gasification systems.
Journal of Membrane and Separation Technology, 2013
The aim of the present study was to investigate the effects of operating conditions (transmembran... more The aim of the present study was to investigate the effects of operating conditions (transmembrane pressure, feed flow rate, and feed concentration) on the fouling attachment probabilities, mass of fouling, and cake height. Polycarbonate flat membrane with a pore size of 0.05 m was used under a constant feed flow rate and cross-flow mode in ultrafiltration of a latex paint solution. The results obtained indicate that increasing transmembrane pressure from 15 to 45 psi lead to an increase in the particle-to-particle (pp) and particle-to-membrane (pm) attachment probabilities from 0.4 to 0.76 and 0.55 to 0.8, respectively. It was observed that both attachment probabilities were significantly decreased when the feed flow rate was increased from 1 to 6 LPM (cross flow velocity from 10.4 to 62.5 cm/s). As a consequence, mass of fouling and cake height were reduced. Increasing the feed concentration from 0.78 to 1.82 kg/m 3 resulted in a substantial raise in the cake height from 4.3 to 18.5 m. Response Surface Methodology (RSM) was used to set up the experimental design. According to regression analysis, two correlation models were obtained in order to predict the fouling attachment probabilities at different operation conditions. Estimated attachment probabilities were used to predict mass of fouling retained by membrane.
The Canadian Journal of Chemical Engineering, 2009
The complex spectral refractive index (absorption index) of fly ash from two generating stations ... more The complex spectral refractive index (absorption index) of fly ash from two generating stations burning Canadian lignite and sub‐bituminous coals have been examined by two different techniques. Ash samples collected at different combustion conditions were analyzed. It is shown that the absorption index of both ashes is in the range of 0.004 to 0.018 in the wavelength range of 0.7‐2.5 μm. The effects of presence of carbonaceous material in ashes, iron content and different operating (combustion) conditions are reported.
An optimal design strategy of a network of fixed bed reactors for Methanol Production (MP) is pro... more An optimal design strategy of a network of fixed bed reactors for Methanol Production (MP) is proposed in this study. Both methanol production and profit spanning a production period of eight years have been set as objective functions to find the optimal production network. The conservation of mass and energy laws on a heterogeneous model of a single industrial methanol reactor was first developed. The model was solved numerically and was validated with industrial plant data. Different reactor network arrangements were then simulated in order to find an optimal superstructure. It was found that a structure of four reactors (two in series in parallel with another two in series) provide maximum production rate. The application of the more realistic objective function of profit showed that a configuration of two parallel reactors is the best configuration. This optimal structure produces 92 tons/day more methanol than a single reactor.
Coaxial mixers have been shown to be effective in enhancing the hydrodynamic stress and shear env... more Coaxial mixers have been shown to be effective in enhancing the hydrodynamic stress and shear environment inside the aerated systems. However, the scale-up study of the aerated coaxial mixing reactors based on a constant mass transfer coefficient has never been reported in the literature. In this study, for the first time, a practical technique is suggested to evaluate the scalability of these systems in terms of a constant mass transfer coefficient. The effects of impeller speed, impeller type, aeration rate, and pumping direction on the mass transfer, power consumption, gas holdup profile, fluid hydrodynamics, and energy dissipation rate were explored for gas dispersion in non-Newtonian fluids inside coaxial mixers through tomography, dynamic gassing-in, and computational fluid dynamics. It was found that a practical approach to preserve the mass transfer coefficient of the large-scale coaxial mixer the same as its small-scale counterpart was to maintain the volumetric aeration rate per working fluid volume constant.
Despite the wide applications of powder and solid mixing in industry, knowledge on the mixing of ... more Despite the wide applications of powder and solid mixing in industry, knowledge on the mixing of polydisperse solid particles in rotary drum blenders is lacking. This study investigates the mixing of monodisperse, bidisperse, tridisperse, and polydisperse solid particles in a rotary drum using the discrete element method. To validate the model developed in this study, experimental and simulation results were compared. The validated model was then employed to investigate the effects of the drum rotational speed, particle size, and initial loading method on the mixing quality. The degree of mixing of polydisperse particles was smaller than that for monodisperse particles owing to the segregation phenomenon. The mixing index increased from an initial value to a maximum and decreased slightly before reaching a plateau for bidisperse, tridisperse, and polydisperse particles as a direct result of the segregation of particles of different sizes. Final mixing indices were higher for polydisperse particles than for tridisperse and bidisperse particles. Additionally, segregation was weakened by introducing additional particles of intermediate size. The best mixing of bidisperse and tridisperse particles was achieved for top-bottom smaller-to-larger initial loading, while that of polydisperse systems was achieved using top-bottom smaller-to-larger and top-bottom larger-to-smaller initial loading methods.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
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