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معالجة واستصلاح الماء المصاحب للنفط العراقي باستخدام طريقة عمود التطويف وتقنية الاغشية == Treatment And Reclaiming of Iraqi Oil Field Produced Water By Flotation Column And Membrane Technology

Author name: هدى كاظم حسن
Supervisor name: ثامر جاسم محمد | قصي فاضل عبد الحميد
General topic: Chemical Engineering
Specific topic: Chemical Processes
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: يتم انتاج كميات كبيره من الماء المصاحب النفطي من قبل شركة نفط الجنوب.يعتبر محتوى النفطي oil - water والاملاح الذائبه TDS من اخطر الملوثات والتي تتم معالجتها باحدث التكنلوجيا في السنوات الاخيره تم استخدام تقنية الاغشية لمعالجة الماء المصاحب النفطي.الهدف م | A large amount of oil field produced water is generated by South Oil Company. Oil - in - Water and TDS are the most serious pollutants for which current treatment technologies are often costly and ineffective in order to reuse water. In recent years, membrane process has been applied for produced water treatment.The aim of the present work is to treat produced water from oil well before being disposed in environment or reused as re - injection to oil well or agriculture water. Oil field produced water is very difficult wastewater to treat and its characteristics change as well to well. The sample test of this study was taken from dehydrator in the DSI/North Rumila/Southern Oil Company in Basrah /Iraq. The treatment process of produced water consists of two stages. The first stage as pre - treatment is achieved by continuous dissolved air flotation (DAF) to reduce the oil content. The second stages, as advanced treatment processes, are accomplished by microfiltration (MF) to reduce the turbidity and nanofiltration (NF) to reduce the salt content as TDS of produced water. The experimental work was carried out using dissolved flotation column is of Perspex glass (0.1 m I.D, 1.5 m height). The bottom of the column connected to a conical joint of QVF glass with a Teflon distributer. The effect of operating parameters (flow rate of produced water, pH, initial oil concentration, flotation time, alum dosage and surfactant of SLS) saturated pressure=5 Atm on the oil content or oil removal efficiency was investigated. The results showed that the oil removal efficiency increases with increasing the flow rate of produced water, the flotation time and coagulants dosage. The oil removal efficiency in DAF unit without coagulants is equal to (80, 94, 95%) for initial oil concentration (30, 50, 70 ppm), respectively at a flow rate 0.03 m3/h and pH=6. While flotation with coagulation, the results indicated that the removal efficiency is equal to 94% (residual oil content <10 ppm) at pH=5, alum dosage=560 ppm, and initial oil concentration=50 ppm, and the removal efficiency is equal to 89.6 at pH=6, alum+SLS dosage=80 ppm, and initial oil concentration=50 ppm. The kinetics of flotation column was studied and it was found that the order of the reaction is changing between zero to first order.The treatment of produced water by membrane technique was carried out by cross flow mode in hallow fiber microfiltration (MF) and nanofiltration (NF). The effect of operating parameter such as transmembrane pressure (TMP) (1, 1.5, 2 bars) with cross flow 20 mL/min, at room temperature, on the flux, rejection, and turbidity and TDS removal was studied. The experimental results by MF manifested that the permeation flux is (108, 156, 611 l/m2.h) and transemembrane pressure is 2 bar at initial turbidity (100, 200, 300 NTU), respectively. But NF, as a final treatment of produced water to reuse, was studied at different feed concentrations (82950, 75050, 67150 ppm) with different TMPS. According to the experimental results, the higher permeation of flux =15 (l/m2.h) at 82950 ppm and 2 bar, was obtained.The experimental results of the removal efficiency were represented in two and three dimensional graphs. An empirical correlation for R% as a function of different parameters (flow rate, pH, and oil concentration) was developed by aided computer using the following formula %R= a + c1*x1n1 + c2*x2n2 + c3*x3n3.

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

Author name: خيرية مطر عيسى الخزاعي
Supervisor name: جمال مانع علي الربيعي
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: يمكن اعتبار نظام المغلي التنوي واحدة من اكثر الطرق فعالية لزيادة التبادل الحراري في منطقة صغيرة نسبيا. انتقال الحرارة في الغليان الحوضي لموائع النانو تم التحقق عنها تجريبيا باستخدام مياه الالومينا AL2O3 ومياه ثاني اوكسيد التيتانيوم TiO2.كموائع نانويه (n | Nucleate boiling regime can be considered one of most effective ways to increase the heat exchange in a relatively small area. Pool boiling heat transfer nanofluid was investigated experimentally using Al2O3 - water and TiO2 - water nanofluids. The experimental test rig consists of boiling vessel and electrically heated plate heating element of stainless steel as heating element. Different concentrations of nanofluids were tested (0.05w %, 0.1w %, 0.3 w%, and 0.5 w %). The nanofluids for Al2O3 and TiO2 were prepared by mixing the( Al2O3 and TiO2) nanoparticles with distilled water in magnetic stirrer for three time periods at (2, 3 and 4) hours and for 1 hour in an ultrasonic bath to suspend the nanoparticles in base fluid. The nanofluids were scanned by scanning electron microscope to ensure well dispersion of nanoparticles in distilled water. Experiments were carried out firstly using pure water then nanofluid to compare the heat transfer enhancement. Results give maximum enhancement ratio in heat transfer rate of (100%) for 0.5% weight concentration for Al2O3 - water nanofluid and (81.82%) for TiO2 - water nanofluid at the same concentration. In both nanofluids the enhancement ratio increases with increased nanoparticle concentrations.This lead to increase in pool boiling heat transfer coefficient.

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

Author name: حيدر مجيد خضير
Supervisor name: محمد فاضل عبد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Higher Diploma
Language: English
University location: Baghdad
First pages:
Abstract: Catalytic naphtha reforming is one of the key processes in petroleum refining, converting gasoline boiling range low - octane hydrocarbons to high - octane compounds which can be blended into gasoline. Other valuable by products include hydrogen and cracked light gases. Modeling of a typical semi - regenerative catalytic reformer of Duara refinery has been carried out involving most its key constituent units. Kinetic modeling of the reactions occurring in the fixed bed reactors connected in series formed the most significant part of the overall simulation effort. A reaction scheme involving (15 pseudo components) connected to gether by a network of 30 reactions for components in the C5 - C10 range has been modeled. The Hougen - Watson Langmuir - Hinshelwood type reaction rate expressions are used to represent rate of each reaction. Deactivation of the catalyst was modeled by including the corresponding equations for coking kinetics. It was found that Paraffines and Naphthenes undergo a continuous reduction through the three reactors while the rate of formation of aromatics is becoming slower as the reactants proceed to the third reactor. The reactor of naphtha reforming could be considered as a hydrogen production.

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

Author name: جعفر مازن جعفر
Supervisor name: نيران خليل ابراهيم | ولاء عبد الهادي نوري
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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

Author name: سها سامي قاسم
Supervisor name: زيدون محسن شكور
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Higher Diploma
Language: English
University location: Baghdad
First pages:
Abstract: 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.

فعالية عامل مساعد محضر ومحفز بمعادن مختلفة لعملية ازالة الكبريت بالهدرجة لزيت الغاز العراقي == Activity of A Prepared Catalyst Promoted By Different Metals For The Hydrodesulfurization of Iraqi Gas Oil

Author name: طارق محمد نايف
Supervisor name: Abdul | Halim A.K. Mohammed | Hussein K. Hussein
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
Abstract: The present work deals with the improvement of Iraqi gas oil containing 1.402 wt. % sulfur by hydrotreating process using different prepared hydrodesulfurization catalysts (Ni - Mo/? - Al2O3, Co - Mo/? - Al2O3, Co - Ni - Mo/? - Al2O3, Ti - Ni - Mo/? - Al2O3 and Re - Ni - Mo/? - Al2O3). All catalysts were prepared under vacuum impregnation to ensure efficient precipitation of metals within the carrier ? - Al2O3. Physical adsorption by nitrogen was investigated, and used for determination of the surface area and pore size distribution of prepared catalysts.The results showed that modified catalysts Ti - Ni - Mo/? - Al2O3 and Re - Ni - Mo/? - Al2O3 have a high surface area 225.1 and 235.23 m2/g respectively, as compered with conventional prepared catalysts Ni - Mo/? - Al2O3 and Co - Mo/? - Al2O3 which their have surface area 178.5 and 191.4 m2/g respectively, and exhibits behavior of type four according to Brunauer, Emmett and Teller (BET) classification, and type H1 according to de Boer classification for hysteresis loop, so, it was concluded that the pores of these catalysts are cylindrical. The performances of all the synthesized catalysts for removal of sulfur and aromatic saturation gas oil were tested at different LHSV (1 to 4 h - 1), temperatures ( 275 to 350 °C), constant pressure 40 bar, and H2/HC ratio 500 ml/ml. The results showed that the sulfur and aromatic content were decresed at all operating conditions for all prepared catalysts. It was found that the sulfur removal from gas oil increases with temperature and decreasing with the space velocity, and the temperature has higher effect on the process of sulfur removal than the space velocity. It was found also that Ni - Mo/? - Al2O3 catalyst is slightly better in sulfur removal (61.5 wt. % ) with than Co - Mo/? - Al2O3 (59.2 wt. %) at the same operation conditions (350 °C and LHSV 1 h - 1), and hydrodesulfurization over Ni - Mo/Al2O3 was improved remarkly by adding Ti and Re promoters. Maximam sulfur removal was 76.81 wt. % using Re - Ni - Mo/? - Al2O3 at temperature 350?C, LHSV 1 h - 1, while minumum aromatic content value is 15.44 wt. % for Ni - Mo/ ? - Al2O3. Calculations showed that the hydrodesulfurization rate expressions fitted with second order reaction kinetics model.The rate constant varied from 0.005 to 0.144 liter/kg.h and the values of activation energy varied from 50.0 to 93.59 kJ/mole for all prepared catalysts. Thiele modulus, for all prepared catalysts was calculated.The lower values of the Thiele modulus (> 0.4) gives strong evidence of negligible pore diffusion limitation.

ازالة المحتوى الكبريتي من وقود الديزل بواسطة الاكسدة والاستخلاص بالمذيب == Desulfurization of Diesel Fuel By Oxidation And Solvent Extraction

Author name: شيم بهجت عبد الكريم
Supervisor name: ودود طاهر محمد | رغد فريد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: يهدف البحث الى ازالة المحتوى الكبريتي من مقطع الديزل المهدرج للتخلص من المركبات الكبريتية الثايوفينية التي تتعذر ازالتها بواسطة عملية الهدرجة المعتمدة في المصافي النفطية. ودراسة افضل الظروف للحصول على اعلى نسبة ازالة.رست الظروف التشغيلية التالية : سرعة ال | Removal of sulfur species from fuels is an increasingly critical environmental issue. Hydrodesulfurization (HDS) removes sulfur compounds, such as mercaptans and sulfides from hydrocarbons; however, some sulfur - containing compounds (such as diebenzothiophene) are very difficult to remove and need deep desulfurization processes.This work was applied to the desulfurized diesel fuel produced from the conventional HDS process for ultra - desulfurization. The used fuel types in this investigation were either real diesel fuel or simulated diesel fuel, where sulfur - containing compound ( dibenzothiophene DBT) converted to its corresponding sulfone by oxidation using hydrogen peroxide as an oxidant and acetic acid as homogenous catalyst, and solvent extraction by using acetonitrile (ACN) or N - methyl - 2 - pyrrolidone (NMP) as extractants.Simulated diesel fuel according to British Petroleum 200B doped with dibenzothiophene (DBT) was prepared, the effect of stirring speed (150, 250, 350 and 450) rpm, temperature (30, 40, 45 and 50) ?C, oxidant/simulated diesel fuel ratio (0.5, 0.75,1 and 1.5) (v/v), catalyst/oxidant ratio (0.125, 0.25, 0.5 and 0.75) (v/v), solvent type, and solvent/simulated diesel fuel ratio (0.5, 0.6, 0.75 and 1) (v/v) were examined in order to obtain the maximum sulfur removal. The results of this work exhibit that the highest removal of sulfur 98.5% for N - methyl - 2 - pyrrolidone and 95.8% for acetonitrile were obtained under the conditions of operating in table below : Stirring Speed (rpm) 350 Temperature (?C) 50 Oxidant (hydrogen peroxide)/simulated diesel fuel ratio 1 Catalyst (acetic acid)/oxidant ratio 0.5 Solvent (ACN or NMP)/simulated diesel fuel ratio 1 Experiments with the above best conditions were carried out on Real diesel fuel obtained from Al - Dora refinery with 1000 ppm sulfur containing compounds. It was found that sulfur removal from real diesel fuel was 62.5% for acetonitrile and 75% for N - methyl - 2 - pyrrolidone.

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

Author name: بسمة محمد كاظم الشاهر
Supervisor name: جمال مانع علي الربيعي
General topic: Chemical Engineering
Specific topic: Industrial Processes
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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.

استخلاص الزيوت العطرية من قشور الحمضيات باستعمال التقطير البخاري بمساعدة المايكرويف == Extraction of Essential Oils From Citrus By - Products Using Microwave Steam Distillation

Author name: سارة جبير صالح
Supervisor name: ابتهال كريم شاكر
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: يهدف هذا البحث الى استخلاص الزيت العطري من ثلاثة انواع من قشور الحمضيات (البرتقال, الليمون, اللالنكي) بطريقتين : التقطير البخاري والتقطير البخاري بمساعدة المايكرويف.ودراسة تاثير عوامل الاستخلاص : (وزن القشور, وقت الاستخلاص,طاقة المايكرويف ونوع قشور الحمضي | The main objectives of this research is to extract essential oil from : orange( citrus sinensis), lemon( citrus limon) and mandarin( citrus reticulata) peels by two methods : steam distillation (SD) and microwave assisted steam distillation (MASD), study the effect of extraction conditions : weight of the sample( 398.56g, 281.8g, 116.76g), extraction time, microwave power( 135W, 265W, 445W) and citrus peel type( orange, lemon, mandarin) on oil yield and compare the results of the two methods, the resulting essential oil was analyzed by Gas Chromatography (GC).Essential oils are highly concentrated substances used for their flavor and therapeutic or odoriferous properties, in a wide selection of products such as foods, medicines and cosmetics. Extraction of essential oil is one of the most time and effort consuming process. Microwave - assisted extraction is a green technique for the extraction of natural products. (MASD) was better than (SD) in terms of rapidity, energy saving and yield. (MASD) gave higher yield than (SD) with shorter extraction time, yield of orange oil extracted by (MASD) was (1.150%) in (35min.) compared to (1.095%) in (45min.) by (SD) process, same results obtained for lemon and mandarin. It was found that the optimal microwave power was (135W) and the yield was : (1.150%, 1.115%, 0.940%) for orange, lemon and mandarin respectively, (MASD) increased extraction temperature in short time and to a higher level compared to (SD).It was found that the optimal weight was (398.56g) and the yield in (SD) was : (1.095%) and MASD (1.091%) for orange oil, same results obtained for lemon and mandarin.The best citrus peel type which gave the highest yield was orange followed by lemon then mandarin in both processes.Limonene is the most abundant component in citrus essential oil, (GC) analysis showed that the amount of limonene increased in low microwave power with long extraction time for mandarin oil it was (84.3891% at 135W in 60min.), while for (SD) it was (83.0271% in 75min.) and decreased with increasing microwave power for orange oil it was (80.9661% at 265W in 35min.) while for (SD) it was (83.2189% in 45min.), (SD) was more convenient to give high amount of limonene because of the graduate temperature rise, while in microwave extraction exposure to low microwave power for long time would give complete recovery and better quality of essential oil.

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

Author name: هبة خميس اسماعيل
Supervisor name: شذى احمد سامح
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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

Author name: ايمن فوزي زوين
Supervisor name: زيدون محسن شكور
General topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: 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.

تثبيط تاكل الحديد الكاربوني الواطئ في حامض الكبريتيك باستعمال كحول البولي فينيل ومستخلص نبات PIPER LONGUM == Corrosion Inhibition of Low Carbon Steel In Sulfuric Acid By PVA And Piper Longum Extracts

Author name: اياد بهاء الدين احمد
Supervisor name: ماجد ابراهيم عبد الوهاب | ابرائيل سركيس يارو
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
Abstract: The inhibitive power of Polyvinyl Alcohol (PVA) and the synergistic effects added on the inhibition power of PVA by two types of Piper Longum (PL) Ethanol Extracts (PLEXT) were investigated toward the corrosion of carbon steel in (0.2N) H2SO4 solution in the temperature range (30 - 60?C) and PVA concentration range (150 - 2000 PPM).The corrosion rate measurements were carried out using the following two standard corrosion measurements techniques.1. Weight loss technique was applied on carbon steel plates to evaluate inhibition efficiency in presence and absence of these inhibitors.2. Electrochemical Techniques were used to validate and support inhibition efficiencies found in weight loss techniques.A detailed study of the experimental methods and results is reported for each test conducted.The weight loss results showed that PVA could serve as a corrosion inhibitor but its inhibition power was found to be low for the corrosion of carbon steel in the acidic media.It was shown that the inhibition efficiency for (PVA) decreased with increasing temperature at a given PVA concentration. On the other hand it was shown that at given temperature the inhibition efficiency of (PVA) was increased with increasing of PVA concentration until a PVA concentration of 2000 ppm PVA was reached then only a slight decrease in inhibition efficiency was observed when increasing PVA concentration further.The Maximum inhibition efficiency reached was about 71 % at 30?C & 2000 ppm (PVA) concentration, calculated by the weight loss techniques.In order to improve the inhibition efficiency of PVA, by adding 6 ml/l of ethanol extracts of piper longum (PL) to a liter of the acid solution in presence of concentrations of PVA 150,500,1000.1500, and 2000 ppm at temperatures (30,40,50, and 60?C) was investigated.Weight loss results showed a jump in inhibition efficiency (% IE) value of the modified inhibitor mixture compared with the presence of PVA alone at all (PVA) concentrations for temperature range considered in this investigation.This study demonstrated the extra inhibition power added by the (PL) fruit extracts to the organic polymer (PVA) used. Maximum inhibition efficiencies recorded were approximately 95% for Piper Longum Extract Number two (PLEXT2) at 30?C and 2000 ppm PVA.The kinetic and thermodynamic parameters regarding the adsorption process of inhibitors used was calculated.It was found that the changes corrosion rates correlates well with the Arrhenius equation in absence and presence of inhibitors.The Results showed that the adsorption of the polymer and the plant extract follows Langmuir adsorption isotherms and the adsorption of the inhibitor molecules on the metal surface is mainly physical, nevertheless the adsorption is believed to be slightly deviated from the Langmuir model at 30?C.Electrochemical analysis of the corrosion process of carbon steel in an electrochemical corrosion cell was investigated using 3 - Electrode corrosion cell coupled with a potentiostat interfaced with a computer which assisted polarization data interception and interpretation.Polarization technique was used to obtain polarization data which was recorded for carbon steel in 0.2N H2SO4 solutions in presence and absence of the inhibitors investigated. Electrochemical runs were done in the (PVA) concentrations of 150, 1000, and 2000 PPM and a temperatures of 30, 40, 50, and 60?C.Tafel slopes, Corrosion currents, and corrosion rates were calculated from polarization curves by Tafel extrapolation method. Results showed corrosion rate trends similar to findings by the weight loss method. It was indicated also that the corrosion of carbon steel in 0.2N H2SO4 is highly activity controlled.Results revealed that the inhibition action is occurring at both anodic and cathodic sites on the metal surface so that both corrosion reactions were affected, so that the composite inhibitor could be considered as mixed - type inhibitor.Electrochemical results confirmed that (PLEXT2) was more efficient as inhibition improvement additive to (PVA) than (PLEXT1) at all experimental conditions range encountered in this study.The highest inhibition efficiency recorded using Tafel polarization method was 83% obtained at 30?C and 2000 ppm of PVA with 6 ml/l PLEXT2.

تحضير الكاربون المنشط من نوى التمر باستخدام كاربونات البوتاسيوم كعامل منشط في ازالة صبغة المثيلين الزرقاء == Preparation of Activated Carbon From Date Stones By K2Co3 Activation For Methylene Blue Dye Adsorption

Author name: اسماء فاضل عباس
Supervisor name: مثنى جبار احمد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: Present study deals with the preparation of activated carbon (AC) from date stones by K2CO3 activation via microwave heating and the removal of methylene blue (MB) dye from aqueous solution by using such carbon as adsorbent. The influence of radiation time (4 - 12min), radiation power (540 - 700W) and impregnation ratio (0.5 - 2.5g/g) on the yield and MB uptake of such carbons were studied. Central composite design was used to determine the optimum preparation conditions and two quadratic models were developed to correlate the preparation variables for both responses.The optimum preparation conditions were reported as 8 min radiation time, 660 W radiation power and 1.5 g/g impregnation ratio resulting in 19.99% yield and 460.123 mg/g MB uptake. From the analysis of variance (ANOVA), it was found that the radiation time had the greatest effect on the yield while impregnation ratio had the greatest effect on MB uptake.The characteristics of AC were examined by pore structure analysis, scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR). The BET surface area and total pore volume were indentified to be 1144.25 m²/g and 0.656 m³/g, respectively. Batch adsorption study was adopted to determine the experimental adsorption isotherm data of different initial concentration of MB (50 - 450 mg/l). The equilibrium data were analyzed using Langmuir, Freundlich and Sips isotherm models. The results showed that the experimental data were well fitted with sips isotherm with maximum monolayer adsorption capacity of 484.7 mg/g. Pseudo - First order, Pseudo - Second order, and intraparticle diffusion models were used to analyze experimental kinetics data with high correlation coefficient for Pseudo - second - order model.

ازالة الكادميوم من المياه الملوثة بالترسيب الكهروكيمياوي باستخدام حزمة من الانابيب الفولاذية متحدة المركز == Removal of Cadmium From Wastewater By Electro - Deposition On Stainless Steel Concentric Tubes Bundle

Author name: انس بديوي سلمان
Supervisor name: عباس حميد سليمون | بسمة عباس عبد المجيد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
Abstract: تم دراسة انتقال الكتلة الخاص بايونات الكادميوم الثنائية الى سطح اسطوانة دوراة مصنوعة من مادة الفولاذ المقاوم للتاكل (كقطب كاثود) بواسطة قياس التيار المحدد لتفاعل اختزال ايونات الكادميوم الكاثودي في محلول كبريتات الصوديوم بتركيز مولار باستخدام خلية ثلاثية | 1 - Mass transfer of Cd+2 ions to a smooth stainless steel rotating cylinder electrode was studied by measuring the limiting current for the cathodic reduction of Cd+2 in 0.5 M sodium sulphate supporting electrolyte by three electrodes cell with stainless steel rotating cylinder electrode working in hydrodynamic voltammetry mode. The studied parameters were electrolyte pH (4, 5, 6 and 7), initial Cd+2 concentrations (50, 100, 200, 300 and 400 ppm) and rotation rates (100, 150, 200 and 250 rpm). Cadmium ions' reduction potential for mass transfer control conditions was found to be - 0.13 V. Diffusion coefficient was determined and correlated with the bulk concentration of Cd+2 in sodium sulphate solution. The increase in pH was found to enhance the mass transfer coefficient and this effect diminishes nearly at pH=7, and the experimental data were well fitted by an empirical dimensionless correlation among the Sherwood number, Reynolds number and Schmidt number. The obtained correlation was : Sh=0.047 ?Re?^0.769 ?Sc?^0.356 For (8015.519 < Re < 20587.07) Reduction potential obtained via the voltammograms constructed by the rotating cylinder cell was applied for the two pilot scale units in order to keep the process under mass transfer control conditions. Parameters studied in these units are : initial cadmium concentration, pH, and electrolyte flow rate. The first pilot scale unit was an electrochemical reactor with smooth stainless steel concentric tubes, and the second one was an electrochemical reactor with stainless steel mesh concentric cylinders.2 - For the stainless steel smooth concentric tubes cathode, mass transfer coefficient was calculated and correlated with initial concentration.Effect of pH on mass transfer coefficient was studied and correlated, and it was found that the effect of pH was found to be completely negligible at pH=7.On the other hand, effect of flow rate on mass transfer coefficient was studied and correlated. Performance of the reactor was analyzed by introducing figures of merit for fractional conversion, specific energy consumption, space time yield and normalizes space velocity. The experimental data were correlated in a dimensionless expression as flows : Sh=0.804?Re?^0.632 ?Sc?^(1/3) For 254 < Re < 1018.3 - For the stainless steel mesh concentric cylinders was adjusted to work under mass transfer control conditions by applying the reduction potential obtained in hydrodynamic voltammetry experiments.Effect of initial cadmium concentration, pH and solution flow rate was studied and analyzed. Mass transfer coefficient was correlated with these studied parameters.Similar to smooth cathode, the mesh cathode showed a negligible response to pH at pH=7.Noticeable enhancement in mass transfer coefficient was investigated by the action of flow rate, and the mass transfer coefficient was correlated with the solution flow rate.The mesh cathode showed a higher conversion than that adopted by the smooth cathode, and showed lower cumulative current efficiency than that of smooth cathode.Mesh cathode showed specific energy consumption, space time yield and normalized space velocity higher than that for the smooth cathode.Experimental data for the mesh reactor were correlated in a dimensionless relation as follows : Sh=1.898?Re?^0.514 ?Sc?^(1/3) For 235 < Re < 943 Cadmium ions reduction reaction was found to follow a first order reaction with respect to Cd+2 concentration, and reaction rate constant was predicted under different operating conditions.

تطبيقات مغنتايت / اثيلين كلايكول كمائع نانوي لانظمة التبريد في الصناعات النفطية == The Application Of Fe3O4 / Ethylene Glycol As Nanofluid For Cooling Systems In Petroleum Industries.

Author name: لقاء صادق جعفر
Supervisor name: تحسين الحطاب
General topic: Chemical Engineering
Specific topic: Electrochemical Engineering
Degree: Master
Language: English
University location: Babylon
First pages:

التكسير الحراري والحفازي لمخلفات البولي اثيلين البلاستيكية في مفاعل شبه دفعوي == Thermal And Catalytic Pyrolysis Of Polyethylene Plastic Waste In Semi Batch Reactor

Author name: فهمي ابو القاسم محمد
Supervisor name: عمار صالح عباس
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

تاثير تصميم موزع الغاز على هيدروديناميكيات ومعامل انتقال الماده في العمود الفقاعي الثلاثي الاطوار == Effect Of Distributor Design On Hydrodynamics And Mass Transfer Coefficient Of Slurry Bubble Column

Author name: هبة علاء عبد الكريم
Supervisor name: صبا عدنان غني | رافع جمال يعقوب
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Salahaddin
First pages:

دراسة في فصل الاوكسجين من الهواء بطريقة الامتزاز بتغير الضغط (PSA) == A Study Of Oxygen Separation From Air By Pressure Swing Adsorption (PSA)

Author name: هبة سعدي ايوب
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Salahaddin
First pages:

استخلاص خام فوسفات عكاشات العراقية بالحوامض العضوية واللاعضوية == Leaching Of Iraqi Akashat Phosphate Ore By Organic And Nonorganic Acids

Author name: محمد يعقوب عيسى
Supervisor name: سيسيليا خوشابا هاويل | بسمة عباس عبد المجيد
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Doctorate
Language: English
University location: Baghdad
First pages:

استخدام تقنية النانو في انتاج الوقود الحيوي من زيت بذور النخيل == Nanotech Biodiesel Production From Date Palm Oil Seeds

Author name: مرتضى عباس علي النعماني
Supervisor name: تحسين علي حسين الحطاب | عماد علي دشر الحيدري
General topic: Chemical Engineering
Specific topic: Electrochemical Engineering
Degree: Master
Language: English
University location: Babylon
First pages:

اختزال مركبات الكبريت من المقاطع النفطية باستخدام تقنية الاكسدة والامتزاز == Reduction Of Sulfur Compounds From Petroleum Fractions Using Oxidation Adsorption Technique

Author name: بان جابر ابراهيم
Supervisor name: NADA SADOON AHMEDZEKI
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

دراسة ريولوجية تركيبية لمحاليل كاربوكسي مثل سليلوز == Structure Rheology Of Carboxymethyl Cellulose (CMC) Solutions

Author name: مصطفى جعفر نايف
Supervisor name: طالب بهجت عمر
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

تعزيز انتقال الحرارة باستخدام مسبباب شدة الاضطراب == Enhancement Of Heat Transfer Using Turbulence Promoters

Author name: عباس نوار زناد
Supervisor name: قاسم جبار محمد سليمان
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

نمذجة ومحاكاة المفاعل المهذب الثانوي الصناعي الشركة العامة لاسمدة المنطقة الجنوبية بالبصرة == Modeling And Simulation Of An Industrial Secondary Reformer Reactor (State Company Of Fertilizers South Region In Basrah)

Author name: علي عاشور الجاسمي الظفيري
Supervisor name: علاء عبد الرزاق جاسم | عباس زكي الاسدي
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Basrah
First pages:

التنبؤ بالمعامل الاجمالي لانتقال الكتلة في استخلاص سائل- سائل للابراج الرذاذة باستعمال الشبكات العصبية الاصطناعية == Prediction Of Overall Mass Transfer Coefficient In Liquid - Liquid Spray Tower Extraction Using Artificial Neural Networks

Author name: مروة سامي نعيم
Supervisor name: مصطفى محمد رضا الفائز
General topic: Chemical Engineering
Specific topic: Chemical Engineering
Degree: Master
Language: English
University location: Basrah
First pages:
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