البحث — المستودع الرقمي العراقي

نتائج البحث: 25 من أصل 530

انتقال الحرارة في الغليان الحوضي باستخدام موائع النانو == Pool Boiling Heat Transfer Using Nanofluids

اسم المؤلف: خيرية مطر عيسى الخزاعي

اسم المشرف: جمال مانع علي الربيعي

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

دراسة حركية التفاعل لوحدة التهديب بالعامل المساعد في مصفى الدورة == Kinetics Study of Catalytic Reforming Process In Daura Refinery

اسم المؤلف: حيدر مجيد خضير

اسم المشرف: محمد فاضل عبد

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: دبلوم عالي

الجامعة: الجامعة التكنولوجية - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

ازالة الكبريت من زيت الوقود باستخدام الاكسدة المعززة بالموجات الفوق الصوتية == Ultrasound - Assisted Oxidative Desulfurization of Fuel Oil

اسم المؤلف: جعفر مازن جعفر

اسم المشرف: نيران خليل ابراهيم | ولاء عبد الهادي نوري

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: Due to the dramatic environmental impact of sulfur emissions associated with the exhaust of engines, sulfur content specification for diesel fuels became more and more stringent worldwide. Last environmental regulations for ultralow sulfur diesel require very deep desulfurization processing, which cannot be met by the conventional hydrodesulfurization process (HDS).The present work focuses on benefiting from integrating an ultrasoundassisted oxidative desulfurization process (UAODS) with the conventional HDS process to produce ultra - low sulfur fuels. The proposed method involves a batch ultrasound - assisted oxidative desulfurization process to desulfurize a previously hydrotreated diesel containing 480 ppm sulfur. The oxidizing system used was H2O2/CH3COOH with FeSO4 being used as a catalyst. An ultrasonic probe system was used to enhance the conversion of sulfur - bearing compounds that exist in diesel to sulfones and sulfoxides to affect their removal by a certain separation method, such as extraction or adsorption.The major influential parameters related to UAODS process have been investigated, namely : ratio of oxidant/fuel, ratio of the promoter/oxidant, dose of catalyst, reaction temperature, intensity of ultrasonic waves. A set of comparative studies were also carried out including type of extraction solvent, effect of initial sulfur content, and type of sulfur separation method. Total evaluation for the treated diesel was performed, including GC - MS analysis which has been used to monitor the change of organic sulfur compounds andhydrocarbons in diesel during the desulfurization process.The oxidation treatment, in combination with ultrasonic irradiation, revealed a synergistic effect for diesel desulfurization. The experimental results showed that the removal efficiency for sulfur compounds could amount to 98%, and sulfur level can be reduced to 12 ppm at mild operating conditions (70 and 1 bar). This indicates that this process is so efficient and promising for the production of ultra - low sulfur diesel fuels.The kinetics of the reaction has been also studied. It was observed that the UAODS of diesel fuels fitted pseudo - first - order kinetics under the studied experimental conditions. During this process, values of the apparent rate constant and activation energy were 0.373 min - 1 and 24 kJ/mol, respectively.

تخمين حركية تفاعل ازالة الكبريت للنفثا الثقيلة العراقية == Prediction of Kinetic Reaction of Iragi Heavy Naphtha Desulferization

اسم المؤلف: سها سامي قاسم

اسم المشرف: زيدون محسن شكور

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: دبلوم عالي

الجامعة: الجامعة التكنولوجية - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: واحدة من التحديات في مصافي تكرير النفط الخام في الاونة الاخيرة هو الحد من محتوى الكبريت من النفثا الثقيلة الى الحدود الدنيا. في هذا البحث تم اخذ مواصفات محتوى الكبريت للنفثا الثقيلة بمعدل 632 جزء في المليون الى 2.5 جزء في المليون، في درجات حرارة التفاعل ( | One of the recent challenges in the petroleum refineries is the reduction of sulfur content of heavy naphtha to the new lower limits. In this reaserch, was taken the specification of the sulfur content of heavy naphtha at arrange 632 ppm to 2.5 ppm, The range of reaction temperatures is (35 - 175) oC and liquid hourly space velocity (LHSV) at range of (1.3 - 1.4) hr - 1 and hydrogen pressure is 35 bars.The simulators are useful tools to manage operation and to improve the profitability of the process. In this study, excel and Matlab program were developed to simulate hydrodesulferization process (HDS) in vapor phase reactor of heavy naphtha hydrotreating unit of Daura refinery, the comparison between the plan results with HDS reactor model results was made.. Based on the model results the optimum operating conditions were determined. Acomputer program MATLAB (Matrix Laborator) it is software for developed code of kinetic parameter estimation problem using the estimation method and least square as objective function and new GA as solving method. The code was implemented on personal computer (intel (R) Core (TM) i3 CPU, 2.39 GHz processor, 2 GB RAM). The function to be minimized was the sum of squares of the differences between calculated and measured concentration.Genetic optimization method was used to define the parameters of desulfurization reaction kinetic. This hydrotreating reaction kinetic model for desulfurization of Daura heavy naphtha was determined for heavy naphtha boiling point range of (35 - 175) C and using a commercial (HDS) catalyst cobalt - molybdenum (Co - Mo) supported of alumina.The result showed that the order of kinetic reaction was first order for heavy naphtha hydrotreating with (Co - Mo) supported of alumina, and the graphically method is more suitable and less error than optimization method for represent the kinetic reaction for heavy naphtha hydrotreating in Daura refinery.

تطبيقات الطرق العددية في التاكل الكلفاني للمعادن المزدوجة == Applications of Numerical Methods In Galvanic Corrosion of Coupled Metals

اسم المؤلف: بسمة محمد كاظم الشاهر

اسم المشرف: جمال مانع علي الربيعي

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: العمليات الصناعية

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: تم دراسة سلوك تاكل معادن النحاس والكربون الصلب والزنك في تراكيز مختلفة من حامض الهيدروكلوريكHCl) ) (0.025، 0.05 و0.075 مولاري ) عند درجات حرارة مختلفة (30، 40 و50 درجة مئوية) باستخدام القياسات الكهروكيميائية (Electrochemical Measurements) في حالة المعا | The corrosion behaviors of metals Copper, Carbon Steel and Zinc in a different concentrations of HCl acid (0.025, 0.05 and 0.075M) at different temperatures (30, 40 and 50°C) were investigated using electrochemical measurements in couple and single state.The galvanic behaviors of coupled metals (Cu - Fe),( Cu - Zn) and (Fe - Zn)were studied using Zero Resistance Ammeter (ZRA) technique, it has been used to measure the galvanic current (Ig) and galvanic potential (Eg) with time. The galvanic corrosion cells for all couples have equal areas of anode and cathode (2×2cm).The galvanic current density (ig) is increased with increasing solution concentration and temperature. The galvanic potential (Eg) is shifted to less negative with increasing solution concentration and temperature and it is close to the corrosion potential of the anode in the couple conditions.The potentiostatic polarization behavior of single three metals (Copper, Carbon Steel and Zinc) in different concentrations of dilute HCl acid (0.025, 0.05 and 0.075M) at temperature (40°C) is found under activation control. The corrosion current density is increases with increasing solution concentration and gives the following arrangement of metals : Cu> Fe > Zn A numerical analysis of galvanic corrosion was presented. The analysis was based on three numerical methods as the boundary element method (BEM), the finite element method (FEM) and the finite difference method (FDM).The potential and current density distributions on the galvanic elements are described by the Laplace equation. The Laplace equation was solved numerically, to determine the potential, current density, and corrosion caused by the galvanic cell using designed computer programs in MATLAB R2014a. The experimentally determined polarization curves have been used in order to define the nonlinear boundary conditions. This boundary value problem has been solved using Newton - Raphson iterative numerical procedure. For the three couple systems (Cu - Fe, Fe - Zn and Cu - Zn), the results obtained for galvanic potential and current density, using the numerical methods (BEM, FEM and FDM) with the overall deviations are 6.689, 10.818 and 18.846 respectively for galvanic current density and 0.631, 1.210 and 1.787 respectively for galvanic potential. From these results it can conclude that the galvanic current density and galvanic potential distribution calculated from the BEM model was in good agreement with the experimental measurements. These are because the main advantages of the BEM over the Finite Element Method (FEM) and the finite difference method (FDM) are high accuracy, discretization on the boundary only which results in a very small number of unknowns, easy dealing with non - regular boundaries and openings that only the domain boundary of interest is required to be discrete, also BEM needs fewer equations and a smaller matrix size than FEM and can solve both finite and infinite domain problems.

تاثير الحماية من التاكل بواسطة الليزر على سبائك الالمنيوم == The Effect of Laser Surface Melting Corrosion Protection On Al Alloys

اسم المؤلف: هبة خميس اسماعيل

اسم المشرف: شذى احمد سامح

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: يهدف هذا البحث الى دراسة تاثير المعاملة بالليزر على تاكل سبائك الالومنيوم (7075, 6061, 5083) المغمورة في محلول ملحي (كلوريد الصوديوم) بمختلف التراكيز. وقد تم اعداد عينات من سبائك الالومنيوم ذات ابعاد (2 ملم) سمك وقطر (25 ملم)، وكانت تجارب الاستقطاب في مح | The objectives of the present project are to generate uniform melted layers, free of large second phases to assess the corrosion resistance of the laser treated surface in comparison with the untreated alloy. So disc samples of (7075, 6061 and 5083) aluminum alloys of 2 mm thickness and 25 mm diameter, have been prepared. Polarization tests were carried out in (M lab potentiostat / galvanostat) (Germany) at 298K temperature and (1.5, 2.5 and 3.5) % wt of NaCl solution. The experiments were carried out before and after laser surface melting by (Nd : YAG, MED - 810) pulse laser, system (Q - Switched Nd : YAG 1064/532nm). Before laser surface melting the results showed that the value of the corrosion current density obviously increases with increasing the concentration of NaCl from 1.5% to 3.5%. As well as higher Cl - ions concentration more negative pitting potential (Epit) of aluminum alloys and decrease in the electrochemical stability of aluminum. The corrosion rate for the specimen 7075 is larger than that of 6061 and 5083 aluminum alloys under the same conditions. So it means that the specimens 6061 and 5083 have high resistance to corrosion in NaCl solution After laser surface melting the results showed that the surface of aluminum alloys became more homogenous and pure after treatment.It was found that the corrosion current density decreases after Laser Surface melting at about three orders than that of untreated samples, therefore, the value of the corrosion rate of laser - treated alloy is smaller than that of the untreated. As well as the pitting corrosion potential after Laser Surface melting obviously shifted to more positive direction for all aluminum alloys in different concentrations of the NaCl solution.

تطبيق اللابفيو والخوارزمية الوراثية في السيطرة على مبادل حراري من نوع الصفائح == Application of LabVIEW And Genetic Algorithm For Controlling of Plate Heat Exchanger

اسم المؤلف: ايمن فوزي زوين

اسم المشرف: زيدون محسن شكور

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: تكرير النفط وتقنيات الغاز

الدرجة: ماجستير

الجامعة: الجامعة التكنولوجية - قسم الهندسة الكيمياوية - فرع الهندسة الكيمياوية وتكرير النفط

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: تم دراسة السلوك الديناميكي لمبادل حراري من نوع الصفائح ( يتكون من 24 صفيحة ) والسيطرة عليه. الموديل النظري للمبادل طور بالاستناد على الموازنة الحرارية لصفائح المبادل.نتائج الموديل توضح السلوك الديناميكي للمبادل حيث تبين انه من الدرجة الاولى بالتقديم ((le | In this work the dynamic behavior of a plate heat exchanger (PHE) (consists of 24 plates) both experimentally and theoretically and the control of the system were studied. A theoretical model for the plate heat exchanger was developed based on the heat balance. A step change is carried in the hot water flow which is considered as a manipulated variable.The results of plate heat exchanger (PHE) showed that the dynamic behavior of plate heat exchanger in this work is dynamically as a first order lead and second order overdamped lag with a significant delay time as shown below : G(p)=(T ?_co (s))/(m ?_h (s) )= ((0.2645s+1.411) e^( - 5.63s))/(0.2156s^2+12.34s+1) The experimental heat transfer measurements of the plate heat exchanger (PHE) indicated that the overall heat transfer coefficient (U) is related to the water flow rate (m) by a correlation having the form : U = 10637 m0.7307 To verify the presented model, temperature control was applied theoretically and experimentally to the plate heat exchanger using conventional P, PI and PID controllers with tuning of control parameters by different methods; Ziegler - Nichols, Cohen - Coon and genetic algorithm to find the best values of proportional gain (Kc), integral time (?I) and derivative time (?D). The time domain specifications like rise time, settling time, overshoot and the performance indices, Integral Squared Error (ISE) and Integrated Time - Weighted Absolute Error (ITAE) were used to evaluate the performance of different control strategies. The PID controller gave better control results of temperature than other controllers, while Ziegler - Nichols tuning method gave better control results than Cohen - Coon. GA technique is the best method in simulation by compare with Cohen - Coon and Ziegler - Nichols methods. Therefore, GA method is suitable as best technique for systems which have shorter constant time.Cohen - Coon and Ziegler - Nichols methods were used in the experimental work to calculate the controller parameters, while GA method was not used in this stage.