توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Modeling and Fuzzy Controller Design for Yeast Fermentation Bioreactor of Ethanol Production
نویسنده(ها): ،
اطلاعات انتشار: دوازدهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۸
Fuzzy controller has been used for a wide variety of chemical applications because of their ability to proper control of process. This paper presents the use of feedback fuzzy controller for temperature control of a continuous yeast fermentation bioreactor. Because of nonlinear and sluggish behavior of this process, proper control of this system is important. In this work, at the first the, process was modeled and then the analytical model of this nonlinear process was used to generate the training data for fuzzy controller. The robustness of this control structure was studied in the case of set point tracking and noise of measurement. Also, the results of fuzzy control are compared with conventional feedback control. It is shown that the servo control properties can be significantly improved by the fuzzy control strategy.<\div>

۲Adaptive Differential Evolution (ADE) for optimization of Non–linear chemical processes
نویسنده(ها): ،
اطلاعات انتشار: ششمین کنگره بین المللی مهندسی شیمی، سال
تعداد صفحات: ۶
Differential Evolution algorithm (DE), one of the evolutionary algorithms, is a novel optimization method capable of handling non–differentiable, non–linear and multimodal objective functions. DE takes large computational time for optimizing the computationally expensive objective functions. Therefore, an attempt to speed up DE is considered necessary. This paper introduces a modification on original DE that enhances the convergence rate. Our Adaptive Differential Evolution algorithm (ADE) uses variable scaling parameter (F) as against constant scaling parameter in original DE at any iteration. Some functions such as logarithmic, exponential, inverse and square for changing F with iteration are examined, and Numerical results suggest that square function has a best performance to reduce solution vectors dispersal and results in faster convergence. The proposed ADE is applied to optimize three non–linear chemical engineering problems. Results obtained are compared with those obtained using DE by considering the convergence history (CPU time and the number of runs converged to global optimum) and error in any iteration. As compared to DE, ADE is found to perform better in locating the global optimal solution, reduces the memory and computational efforts by reducing the number of iteration to reach a global optimal solution for all the considered problems.<\div>

۳Investigation of Water Coning in Fractured Reservoirs Based on Single Porosity Model
نویسنده(ها): ، ، ،
اطلاعات انتشار: ششمین کنگره بین المللی مهندسی شیمی، سال
تعداد صفحات: ۵
Simultaneous production of oil and water from the oil well because of unbalancing between viscous and gravitational forces known as water coning phenomenon, hinders the oil production. Coning phenomenon is more challenging in fractured reservoir owing to their intrinsic heterogeneity. In order to study the coning phenomenon in fractured reservoir, one should solve the two phase governing partial differential equations of oil and water flow in heterogeneous porous media for radial system. Commonly fractured reservoirs are considered as matrix and fracture mediums and understanding the effect of interaction of matrixes and fractures on fluid flow are really a challenge. In this study we used a cylindrical system to simulate water coning around a single well in fractured reservoirs while utilizing governing partial differential equations in r and z directions for non–fractured reservoirs. After gridding of the system in r and z directions, several shells and discs will be created in vertical and horizontal directions respectively. Attributing proper permeability and porosity to some shells and discs, they can be imagined as vertical and horizontal fractures respectively. The influences of intensity and orientation of a fracture systems on breakthrough time of water into the wellbore are investigated based on above model.<\div>

۴Dynamic Modeling and Simulation of DME Synthesis in Fixed bed reactor
نویسنده(ها): ، ،
اطلاعات انتشار: ششمین کنگره بین المللی مهندسی شیمی، سال
تعداد صفحات: ۶
Dimethyl Ether (DME) as a clean fuel is produced in an adiabatic fixed–bed reactor by the methanol dehydration, in industrial scale. Dynamic modeling of an industrial catalytic fixed bed reactor for DME synthesis has been subject of current study. In this study, DME reactor is modeled heterogeneously with consideration of the heat and mass transfer between catalyst pellets and reactant gas. In order to estimate the DME production and dynamic temperature profile, the reactor model which is a set of partial and ordinary differential equations and algebraic equations has been solved numerically. Steady state results of model have been compared with industrial data. The comparison successfully confirms validity and accuracy of proposed model.<\div>

۵Real time optimization of methanol Reactor using evolutionary algorithm
نویسنده(ها): ،
اطلاعات انتشار: چهاردهمین همایش بین المللی نفت، گاز و پتروشیمی، سال
تعداد صفحات: ۹
In this article real time optimization RTO of industrial shell and tube methanol reactor is presented. Mathematical modeling of reactor is used as case study and inlet concentrations such as CO,CO2,H2,H2O and methanol are used as disturbance. Outlet concentration is maximized by adjusting shell temperature as manipulating variable . differential evolution DE is used for optimization. the optimizer initiates every hour and determines the optimal set point. reduction of catalyst activity is updated as model parameter every 24 hours. by using the proposed algorithm and control loop, production of methanol is increased up to 15%.<\div>

۶application of artificial neural networks for identification of distillation column
نویسنده(ها): ،
اطلاعات انتشار: یازدهمین کنفرانس مهندسی برق، سال
تعداد صفحات: ۸
this paper demonstrates that neural networks can be used effectively for the identification of nonlinear dynamical systems two different kinds of neural networks multi layer perceptron MLP and radial basis function RBF networks have been developed to infer compostions of a ternary distillation column from temperature measurements the reliability of the developed setimators is discussed with respect to disturbance on steam reflux rate feed flow rate and feed compositions the estimation results of MLP and RBF networks are represented respectively and some comparisons are carried out<\div>

۷Estimation states and covariance of the process noise for cell retention process
نویسنده(ها): ،
اطلاعات انتشار: یازدهمین کنفرانس مهندسی برق، سال
تعداد صفحات: ۹
In the present work the use of extended kalman filter EKF to infer the outlet compositions and growth rate of the acetone –ethanol fermentation process from outlet gas CO2 measurement have been discussed in order to tune the filter Q matrix different methods consist of trial and error loan fotopoulos modified fotopoulos and continuous case have been investigated for process noise covariance matrix the reliability of the developed estimator is discussed with respect to disturbance on CO2 concentration the performance of the estimator has been evaluated by comparison with other filters such as wiener and linearized kalman filter as well as simulation and experimental results.<\div>

۸RPEDICTION OF SOLUBILITY OF CO2 IN AN IONIC LIQUID WITH PR EOS PAIRED WITH WONG –SANDLER MIXING RULE IN SUPER CRITICAL
نویسنده(ها): ، ، ،
اطلاعات انتشار: اولین کنفرانس بین المللی نفت، گاز، پتروشیمی و نیروگاهی، سال
تعداد صفحات: ۴
Ionic liquids have achieved special attention from the scientific community in recent years and many studies involving different features of properties and applications of Ils have been presented even though the first representative has been known since 1914 ionic liqids have only been investigated as solvents for transition metal catalysis in the past ten years. publications to date show that replacing an organic solvent by an ionic liquid can lead to remarkable improvements in well–known processes in this work we examined the prediction capability of gas liquid equilibrium of CO2 and ILs from the use of the peng–robinson equation of state and UNIFAC activity coefficient model combined with wong sandler mixing rule and then the model compared with experimental data.<\div>

۹Hydroformylation of Propylene Reactor Catalyst Activity Model Using Adaptive Neuro–Fuzzy Inference System and Differential Evolution (DE) Algorithm
نویسنده(ها): ، ، ،
اطلاعات انتشار: چهاردهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۴
Olefin hydroformylation is one of the important intermediate processes for production of Oxoalcohol. One of the important operating problems in Oxo process is the catalyst deactivation.Industrial experience showed that the catalytic activity of rhodium\TPP complex decreases gradually in normal operating conditions, even while there are no poisons and inhibitors. In thispaper we used data from the industrial unit during the starting 822 days of the process. A generalized power law expression (GPLE) is used for predicting catalyst activity. The coefficients of GPLE have been optimized using Differential Evolution (DE) algorithm, which is a strong andeffective optimization technique. Also a model based on the adaptive neuro–fuzzy inference system (ANFIS) has been proposed for estimating catalyst activity. By comparing both models with industrial data, it was seen that ANFIS is able to predict catalyst activity more accurately than GPLE. Finally, it was observed a good agreement between two models and plant data.<\div>

۱۰Effects of various carbon sources on the produced biodemulsifier by Paenibacillus alvei ARN63 in order to crude oil demulsification
اطلاعات انتشار: چهاردهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۵
Paenibacillus alvei ARN63 as a biodemulsifier–producing bacterium has represented incredible demulsifying ability. The produced lipopeptidebiodemulsifier can be used in crude oil industry as an environmentally friendly(green) substance, containing no toxic component. Due to increase production of biodemulsifier, as a type of biosurfactant, the culture conditions for the strain were optimized. For this goal, the effect of different carbon sources and C\N ratios(carbon concentration) were examined in detail at constant temperature, pH, shaking speed (rpm) and nitrogen source. Biodemulsifier synthesis and cellgrowth were determined via measurement of surface tension and optical density (OD600), respectively. Subsequently, to investigate its demulsificationperformance, the bottle test was carried out. Normal paraffin compounds such as C7H16 and C10H22 and C12H26 favored the synthesis of this biodemulsifier. Thebest results were obtained employing C7H16 as carbon source with C\N ratio of 63.13. The surface tension was reduced (from 62.5 mN\m) to 32.3 mN\m in 72 h, and demulsification ratio reached to approximately 65%.<\div>

۱۱Naphtha Cracking through Pulsed DBD Plasma Reactor
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۱۲
In this present, conversion of a model refinery cut (Naphtha) in a novel pulsed DBD plasma reactor was investigated in laboratory scale using unipolar pulsed high voltage power source. Continuous hydrocarbons cracking and instant generation of light hydrocarbons (C1–C3 like CH4, C2H4, C2H6 and C3H6,) and H2 were studied at room temperature and atmospheric pressure by using argon as a plasma carrier gas. Finding the optimal design parameters of liquid hydrocarbons cracking was the main purpose of this study. So effect of some process parameters like carrier gas flow rate, inner electrode diameter and electrode material (copper, brass, aluminum, iron and steel) was investigated on content and quality of products. Energy efficiencies, generation of hydrogen, product selectivity, breakdown voltage and etc. were determined and discussed. Results show that carrier gas flow rate, inner electrode diameter and electrode material, all affect the energy efficiency of a plasma reactor. Steel and Iron materials have maximum energy efficiencies. The best performance in reaching notably high efficiencies was at 2.68 mm inner electrode diameter. In this condition efficiency rise to 106.23 (lit\KWh) for 50 ml\min argon flow. The results showed that pulsed DBD systems are capable for cracking liquid hydrocarbon with high conversion efficiency and are an important piece of technology for replacement refinery cracking operations. It is also a very promising process for the production of hydrogen–rich gas with the important advantage to be free of carbon monoxide thus it can be considered as a high–quality hydrogen production method<\div>

۱۲Experimental Investigation of Secondary Oil Recovery in Fractured Media
نویسنده(ها): ، ، ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۷
Naturally fractured reservoirs (NFRs) contribute in large extent of oil and gas production to the ever increasing market demand of fossil energy. It is believed that waterflooding can more thandouble the recoverable reserves of many developed oilfields especially the fractured ones at low capital investment. Hence, as the methodological plan of this study, unconsolidated packed models of cylindrical geometry surrounded by fractures are utilized in order to perform a series of flowvisualization experiments during which the contribution of different parameters such as the extent of matrix wettability (water–wet, oil–wet, fractional wet and mixed wet), absolute permeability, and the physical oil properties (e.g., density, and viscosity) is studied. The results show that therecovery efficiency from water–wet media is higher than other cases. Furthermore, by decreasing the model permeability and increasing the oil viscosity during secondary recovery process, the recovery efficiency reduces<\div>

۱۳Experimental study of Iron–Control Chemicals for High Temperature Sour Gas Wells
نویسنده(ها): ، ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۱۰
Iron control agent is an important additive of acidizing. Iron compounds that precipitate during acidizing can reduce reservoir permeability in the critical near–wellbore area. In this study, the applicability of reduction for several ferric ion reducing agents is investigated. Reduction strengths and time duration for complete reduction are determined for all presented ferric ion reducers.Mixtures include ferric ion reducer and various catalysts are prepared and compared with eachother. Thioglycolic acid is determined as the best ferric reducing agent and also potassium iodide as the best catalyst. Therefore, mixture of thioglycolic acid and potassium iodide is more effective among all mixtures. This mixture is compared with commercial reducing agents obtained from BJ service at high temperature and in the presence of hydrogen sulfide. Performance of the proposed mixture is better than the commercial reducing agent. This proposed iron control additive is appropriate for acidizing at high temperature in sour gas wells.<\div>

۱۴Hydrogen Production Using Liquid Hydrocarbon Cracking through Pulsed DBD Plasma Reactor
نویسنده(ها): ، ، ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۱۱
In this present, conversion of a model refinery cut (Naphtha) in a novel pulsed DBD plasma reactor was investigated in laboratory scale using high voltage pulse generator. Continuous hydrocarbons cracking and instant generation of light hydrocarbons (C1–C3 like CH4, C2H4, C2H6 and C3H6,) and H2 were studied at room temperature and atmospheric pressure by using argon as a plasma carrier gas.Finding the optimal design parameters of liquid hydrocarbons cracking was the main purpose of this study. So effect of some process parameters like applied voltage and frequency (applied power) and feed flow rate was investigated on content and quality of products. energy efficiencies, generation of hydrogen, product selectivity, breakdown voltage and etc. were determined and discussed.Results show that, compared with frequency, applied voltage has dominant effect on power consumption. Also higher feed flow rate, increase power consumption.Applied voltage, applied frequency and feed flow rate, all affect the energy efficiency of the plasma reactor. It will increase as the feed flow rate decreases and increase as applied voltage and frequency increase. The best performance in reaching notably high efficiencies was at 7 KV and 18 KHz. In this condition efficiency rise to 79.38 (lit\KWh) for 1ml\min of feed injection.Hydrogen gas concentration was between 30%–60% in the produced gas. The hydrogen output is significantly affected by applied voltage and frequency. The generation rate of the hydrogen gas was 2.76 ml\min for an input energy of 5.38 W with energy efficiency of 51.08 lit\kWh which H2 concentration was 60.3% (maximum).The results showed that pulsed DBD systems are capable for cracking liquid hydrocarbon with high conversion efficiency and are an important piece of technology for replacement refinery cracking operations. It is also a very promising process for the production of hydrogen–rich gas with the important advantage to be free of carbon monoxide thus it can be considered as a high–quality hydrogen production method.<\div>
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