البحث — المستودع الرقمي العراقي

المستخلص: This work presents an experimental study of the drag - reduction performance of two water - soluble polymers, Polyacrylamide(PAAM) as flexible, linear synthetic polymer and Xanthan Gum(XG) as a rigid polysaccharide from natural resources. The flow loop used consisted of 0.5 O.D. inch straight pipe with a test section of 3 m length. A 0.5 inch O.D. vertical tubing with elbows was also included to compare the drag - reduction behavior between both tubing configurations. Various concentrations of polymeric additive and water flow rates were tested. The results show that the drag - reduction in vertical piping are significantly lower than in straight type for both polymer type. The dragreduction efficiency of Xanthan Gum agent is much lower than polyacrylamide. Higher concentrations of XG about 150 ppm is required to get exactable drag - reduction performance about 12.84% in the straight pipe. While about 40.3% drag - reduction was achieved with about 50 ppm Polyacrylamide with the same conditions. Moreover, the drag - reduction efficiency of XG can be improved by mixing with Polyacrylamide agent at a given conditions.Part of the experimental work was devoted to study the performance of Polyacrylamide as drag - reducing agent with the existence of small amounts of sodium chloride acts as an inhibitor to the ability of the additive, resulting in lower drag - reduction probably due to collapse of PAAM at more compact structure with the addition of sodium chloride as strong ionic salt.Polyacrylamide and Xanthan Gum additive undergo undesirable mechanical degradation with increasing of circulation time, leading to lower drag - reduction performance. The molecular degradation is likely to occur at low additive concentrations and low turbulence flow, in vertical piping, since the polymeric additives are exposed to shear stresses.Further attempt was done in present investigation to find correlations for accurately predicting drag - reduction characteristics of drag - reducing agents, used in published works. A published time scale hypothesis for prediction of drag - reduction values, the friction factor data as a function of the polymer concentration, shear stress, Reynolds number, pipe diameter. The experimental friction factor results were taken from a published work for gas oil with polyisobutylenes. Good agreement between measured and predicted friction factor. Further attempt was made to correlate the mechanical degradation ability by modifying the Kouraush, Williams and Watt (KWW) equation. The experimental data were taken from a published work for Polyethylene Oxide. The modified equation was found to fit experimental data better than the original KWW equation.

دراسة تاكل الصلب الكربوني في محلول ملحي والمنتجات البترولية بوجود غاز ثاني اوكسيد الكربون == Studying of Carbon Steel Corrosion In Salt Solution And Petroleum Products In Presence of CO2

اسم المؤلف: نضال احمد شاكر

اسم المشرف: شذى احمد سامح | شروق طالب الحميري

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: يتضمن البحث دراسة سلوك التاكل للصلب الكربوني في محلول ملحي من (3.5wt%NaCl) ومشبع طبيعيا بالهواء بوجود غاز CO2 المستخدم في انابيب النفط. وتم تصميم منظومة القطب الاسطواني الدوار (RCE) لانجاز الدراسة.واجريت تجارب الاستقطاب في ظروف الجريان المضطرب باستخدام | The present work is to study the corrosion behaveior of carbon steel, in naturally aerated 3.5wt% NaCl (brine solution) and petroleum products in presence of CO2. A rotating cylinder electrode (RCE) system were used to study the potentiostatic polarization experiments, under turbulent flow conditions, using 3.5wt% brine solution as electrolyte at different temperatures (298, 308, 318 and 328)K and rotating speed of (0, 100, 200, 300 and 400)r.p.m. at each temperature.Similar experiments were carried out in 3.5wt% brine solution using CO2 gas at (32 ml/sec) flow rate.Corresponding experiments by weight loss were carried out in 3.5wt% brine solution with compunds of : - 1. Kerosene + 10V% brine solution.2. Gas oil + 10V% brine solution. At 328Kand flow rates of (0 and 400) r.p.m.3. Similar experiments were carried out in kerosene + 10V% brine solution at (298, 308 and 318)K and static condition speed of (0) r.p.m at each temperature.4. Experiments were carried out in pure kerosene at a temperature of (298 and 318) K and speed of (0) r.p.m.All above experiments were carried out with and without CO2 gas.The results indicated that the corrosion rate of carbon steel was increased in presence of CO2 gas.The anodic dissolution kinetics were activation control processes affected by temperature.The activation energy of carbon steel with CO2 gas system (2.87 - 1.8) Kcal/mol at different r.p.m. was lower than that without CO2 gas system of (11.4 - 1.7) Kcal/mol at different r.p.m.The corrosion potentials without CO2 gas were shifted to the noble direction with increasing flow rate at a constant temperature, whereas such potential were shifted to the less noble direction with increasing temperatures at a constant speed. However, the corrosion potential with CO2 gas was more noble than that obtained without CO2 gas.The corrosion rate is increased with increasing temperature and velocity. The results indicated that the corrosion rates of ( gas oil +10V% brine solution ) are higher than that of (kerosene +10 V % brine solution) with and with out CO2 gas, and the corrosion rate of pure kerosene is lower than that of (kerosene+10V% brine solution) with and without CO2 gas.In the presence of CO2 gas the results indicated that corrosion rate increases due to continuous dissoultion of iron ion and formation of weak carbonic acid. The carbonic acid accelarteed corrosion rate and affected carbonate and hydrogen ion, which increased the cathodic reactions on the metal surface.

دراسة تاثير بعض متغيرات عملية الترسيب الكهروكيمياوي للنحاس على كفاءة العملية وخواص المسحوق المنتج == The Study of The Effect of Some Variables in Electrochemical Deposition of Copper Powder on The Efficiency of Process And Powder Properties

اسم المؤلف: ميادة نوار نصيف

اسم المشرف: فاروق منصور مهدي

الموضوع العام: الهندسة الكيمياوية

السنة: 2010

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: جامعة تكريت - كلية الهندسة - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: صلاح الدين

الصفحات الاولى:

المستخلص: يهدف البحث الى اجراء دراسة عملية لانتاج مسحوق النحاس باستعمال طريقة الترسيب الكهروكيمياوية مع دراسة تاثير عدد من المتغيرات التي تؤثر في كفاءة العملية والوقوف على طبيعة تاثير كل منها. تمت دراسة تاثير كل من كثافة التيار وزمن الترسيب ودرجة حرارة وسط الترسيب | The present study aims to produce copper powder by the electrochemical deposition method. In this work, the effect of current density, deposition period, electrolyte temperature, distance between electrodes, ratio of anode to cathode surface area and cathode rotation on the current efficiency and powder properties such as apparent density, grain size, grain size distribution and grain morphology on powder properties and current efficiency are studied. A deposition system composed of Perspex cell, two copper electrodes ( 96.8% purity), electrolyte composed of 90g/l CuSO4 and 120g/l H2SO4 as well as the electrical connections. Betts method was followed by this study.The automatic sieve shaker was used to determine the grain size, while the atomic spectroscopy was used to determine copper purity. Moreover, both optical microscope and SEM were used to estimate powder morphology. It is found that current efficiency is increased with increasing deposition time and electrolyte temperature. It is also found to be decreased with increasing current density, distance between the electrodes, ratio of anode to cathode surface area and rotation of cathode electrode. The results showed also that particle size is increased with increasing the distance between the electrodes and increased with increasing the ratio of anode to cathode surface area and cathode rotation. Further more, the obtained data indicated that the maximum and minimum achieved fine grain percent (

اداء المبادل الحراري الارضي الاحادي المسار باستخدام موائع تشغيلية مختلفة == Peformance of A Single Pass Earth - Tube Heat Exchanger Using Different Working Fluids

اسم المؤلف: مصطفى جواد نعمة

اسم المشرف: غزوان احمد محمد | عباس خلف محمد

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: جامعة بغداد - كلية الهندسة - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: العديد من التقنيات استخدمت لتحسين معدل الانتقال الحراري لاختزال حجم المبادلات الحرارية وتشغيلها باقل كلفة0المبادلات الحرارية الارضية استخدمت وبشكل واسع وذلك لتحسين تقنيات التبادل الحراري في العديد من التطبيقات الصناعية0المبادل الحراري الارضي هو اداة تسمح | Several techniques have been applied to enhance heat transfer rate in order to reduce the size of heat transfer devices and also operating cost. Earth tubes have been used as one of the most widely used heat transfer enhancement techniques in several industrial applications. Earth tube heat exchanger is a device which permits transfer of heat from fluid to deeper layers of soil and vice versa.The results of the heat transfer characteristics in earth tube heat exchanger are presented. The experimental test section is made of 50 m carbon steel pipe of 19.05 mm inner diameters and 25.95 mm outer diameters. The pipe was buried 2 m deep below ground surface. Water and gasoil were used as working fluids in the experimental runs. Experiments were performed under conditions of volumetric flow rates ranging from 0.5 to 2 m3/h and inlet working fluids temperature is between 35 to 70?C at winter season and between 50 to 70?C at summer season. Working fluids temperatures were measured at five points with equal length by thermocouples placed inside the pipe. Also, soil temperatures were measured at these points by thermocouples placed 0.5 m apart from pipe. The effects of working fluid flow rate, inlet temperature, pipe length on the overall performance of the earth tube heat exchanger was investigated at winter and summer seasons, respectively.It was shown that the heat transfer rate of the working fluid increases as the pipe length and inlet temperature increase, or volumetric flow rate decreases. Furthermore, the heat transfer rate in the first half of the pipe represents (33.3 to 87.5%) from the total heat transfer rate, depending on working fluid operating conditions. Also, it was noticed that the heat transfer rate in summer days is less than in winter days. Coefficient of performance (COP) analysis was also carried out to characterize the system performance at different operating conditions. The experimental earth tube heat exchanger (ETHE) system was attained a maximum COP of 45.589 at winter tests and 17.818 at summer tests for water as working fluid. But, the maximum COP was reached only 28.52 for gasoil as working fluid at summer.

معالجة الماء الحاوي على النفط في حقول نفط العراق الجنوبية == Oily Water Treatments For Southern Iraqi Oil Fields

اسم المؤلف: عقيل شيخة عرفات

اسم المشرف: خالد مخلف موسى

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: جامعة النهرين - كلية الهندسة - قسم الهندسة الكيمياوية

اللغة: الانكليزية

النص الكامل من المصدر: https://nahrainuniv.edu.iq/sites/default/files/Combined_320.pdf

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: عمليات الحفر تنتج كميات كبيرة من الماء الملوث يعرف بالماء المنتج او الماء المنتج من البئر. مختبريا تم التحقق باستخدام Autoclave بحجم لتر واحد مصنوع من مادة الصلب stainless steel لمعالجة الماء المنتج من حقول الرميلة الشمالية والزبير الخطوة الاولى استخدمت م | The oil drilling operations create large quantities of contaminated water known as “Produced Water” (PW), or water that is produced from the well. An experimental investigation was conducted using 1litter stainless steel autoclave to treat the oily water produced from North Rumaila and Zubair oil fields. The first approach was a pretreatment to remove solid particles using sedimentation with and without flocculation. The second approach included studied the effect of pH, pressure, temperature, salinity, operation time, outlet time and RPM. The third approach was investigate the effect of the surfactants (detergents and alcohol) to reduce surface tension, finally, was addition of some sorbents like polypropylene, polyethylene, used plastic and sawdust.The ranges of salinity, pH, pressure and temperature were selected according to the PW conditions which out from dehydrator and desalter (80000 ppm, 6, 3bar and 60°C respectively), the RPM of mixer was selected to satisfy laminar flow, while the time of operation and outlet product represented the minimum residence time in batch reactor and its discharge to choose the minimum design cost. The results showed that the best conditions were : - Pressure =1 bar, temperature =45°C, mixer speed =300 RPM, treating time =15 min and skim time starting =5 minutes. Best additives to reduce surface tension : ethanol volume = 0.05vol %, powder detergent = 400 mg/litter and liquid detergent volume = 0.03vol%. Best sorbents : Sawdust amount addition = 2.5 gm, polypropylene = 4 gm, polyethylene = 3 gm and used plastic = 2.5 gm The results showed that using polymers made a great change in the oil recovery percent (all the oil was recovered).

اكسدة ايون الحديدوز الى ايون الحديديك باستخدام المضافات في العمود ذو الفقاعة == Oxidation of Ferrous To Ferric Ion By Additives in Bubble Column

اسم المؤلف: صباح محمد حسن الجبوري

اسم المشرف: رافع جمال يعقوب

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: جامعة تكريت - كلية الهندسة - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: صلاح الدين

الصفحات الاولى:

المستخلص: تم دراسة اكسدة كبريتات الحديدوز الى كبريتات الحديديك من خلال التركيز على اختبار تاثير الظروف التشغيلية للمنظومة على عملية اكسدة كبريتات الحديدوز بالهواء ومن ثم دراسة تاثير المضافات في اتمام عملية الاكسدة باستخدام الاوكسجين في العمود الفقاعي. تم استخدام ا | This study was discussion converting of ferrous sulfate to ferric sulfate by oxidation with using the bubble column and concentrates by using air and then studied the effect of additives to complete the oxidation with oxygen. Air is used as an oxidation agent in the first step to study the oxidation reaction in bubble column with(5 cm inside diameter ,120 cm tall ), in this part of process, studying the operation condition on the oxidation and determining the rate of conversion. Temperature ( 50,60 and 70 )°C ,air flow rate (100,150,200 and 250)L/h and initial concentration of ferrous (0.5 , 0.25 , 0.1 and 0.05 )M with fixing the pressure slightly up to 1 atmosphere are used to study the performance of the parameters (initial concentration ,temperature and air flow rate on oxidation ferrous sulfate.The effect of these conditions are studied throughout the experimental work to increase the conversion rate of ferrous sulfate.The results are shown that the maximum conversion rate is 53.5% at the temperature 70 °C ,air flow rate 150 L/h and initial concentration of ferrous is 0.1M.The results of the optimum conditions are depended on the second part of this work by using oxygen gas and additive material, (CuSO4, KMnO4, H2O2 and HNO3) at the different concentration (100 , 200 , 300 , 400 , 500 ) ppm, the effect of each material is studied to show the conversion rate of ferrous to ferric sulfate.The test of these material gave different results for each material and gave different result for each concentration of additive on the conversion rate of ferrous.The best result is that the conversion rate is 81.1 % by using CuSO4 at additive concentration 400ppm, the conversion rate is 78.9% by using HNO3 at concentration of additive 200 ppm , the conversion rate is 73.1% by using KMnO4 at concentration of additive 400 ppm and the conversion rate is 70% by using H2O2 at concentration of additive 200 ppm.Mathematical correlation for each additive and the main operating variables on oxidation of ferrous to ferric sulfate are solved by using (Excel) program are illustrated : - (d[?Fe?^(+2)])/dt=0.612067 t+0.011378 Cadd ? 2.86622.

ازالة المحتوى الكبريتي بالاكسدة العميقة باستخدام الكاربون المنشط المحفز == Deep Oxidative Desulfurization Using Catalyze Activated Carbon

اسم المؤلف: ياسمين منذر جاعد

اسم المشرف: ودود طاهر محمد

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: جامعة بغداد - كلية الهندسة - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: ازالة المحتوى الكبريتي من الوقود هي قضية بيئية حاسمة على نحو متزايد. عملية الهدرجة(HDS) تزيل المركبات الكبريتية مثل المركبتان والكبريتيد من الهيدروكربونات، ولكن بعض الكبريت - يحتوي على مركبات (مثل dibenzothiophene) من الصعب جدا ازالتها وتحتاج عمليات عميقة | 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 dibenzothiophene) are very difficult to remove and need deep desulfurization processes.This work was applied to the desulfurization diesel fuel produced from the conventional HDS process or ultra - desulfurization. The used fuel types were either real diesel fuel or simulated diesel fuel, where sulfur - containing compound (dibenzothiophene) converted to its corresponding sulfone by oxidation using hydroperoxide as an oxidant and formic acid as cocatalyst with activated carbon (AC), in addition to its adsorbent virtue. Simulated diesel fuel according to British Petroleum 200B doped with dibenzothiophene was prepared.The experimental study was divided into two parts, preliminary study, that include thermally (activated carbon with heat treatment (ACH)) and chemically treatments (i.e. activated carbon impregnated with copper (Cu/AC), activated carbon impregnated with nickel(Ni/AC), activated carbon impregnated with copper and nickel (Cu - Ni/AC) and activated carbon with nitric acid treatment (ACN) ) to the parent activated carbon, these types were tested at different operating conditions (i.e. temperature = 25 and 60 ?C, pH=2, H2O2/diesel fuel ratio=3/100 and activated carbon doses = 0.7 and 1.0 g) to achieve the best one that gives higher desulfurization efficiency. ACM that is a mixture of ACH and ACN (equal percentage) gives 80% sulfur removed at operating conditions of temperature= 60 ?C, pH=2, H2O2/diesel fuel ratio=3/100 and ACM doses = 0.7 g. In general, the activity of activated carbons as follows ACM >ACN > ACH > Ni/AC > Cu/AC > Cu - Ni/AC > parent AC While, the second part represents the main study, that deals with the desulfurization process in details, using ACM with operating conditions of temperature of 60 - 80 ?C, pH of 0 - 4, H2O2/diesel fuel ratio of 3/100 to 7/100 and ACM doses of 0.5 to 1.0 g Maximum desulfurization efficiency achieved was 92.3% at operating conditions of temperature= 80 ?C, pH =0, H2O2/diesel fuel ratio= 5/100 and ACM dose =1.0 g.Finally, two experiments with the best conditions above were done on the real diesel fuel. Maximum desulfurization efficiency was 25% at temperature= 80 ?C, pH =0, H2O2/diesel fuel ratio= 5/100 and ACM dose =1.0 g.

معالجة مياه المصب العام للحقن في حقل الناصرية النفطي == Water Treatment of Main Outfall Drain For Injection In Nasiriyah Oil Field

اسم المؤلف: جعفر جبار مدلول

اسم المشرف: احمد فائق العلوي

الموضوع العام: الهندسة الكيمياوية

السنة: 2014

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: جامعة بغداد - كلية الهندسة - قسم الهندسة الكيمياوية

اللغة: الانكليزية

مكان الجامعة: بغداد

الصفحات الاولى:

المستخلص: يهدف العمل الحالي لانتاج مياه ملائمة للحقن في حقل الناصرية النفطي من المصب العام يتكون الجزء العملي من هذا البحث من ثلاثة مراحل(1) التخثير/ التلبد , (2) مرشح ماء الجاذبية الطبيعية او غشاء دقيق و(3) تقنية اغشية النانو. المرحلة الاولى, تخلص عملية التخثير/ | The aim of the present work is to produce water appropriate for injection in Nasiriyah oil field from Main Outfall Drain (MOD). The experimental work in this research consists from three stages (1) coagulation/ flocculation, (2) natural gravity water filter or microfiltration membrane (MF) and (3) nanofiltration membrane (NF) technology. The first stage, coagulation/flocculation process removed the suspended solids from MOD and reduced the turbidity to the demand limits. The variables studied were initial turbidity (11.8 - 100 NTU), coagulant dosage (0 - 55 ppm), speed of the slow mixing step in the jartest apparatus (2nd step) (20 - 40 rpm), time of 2nd step (20 - 40 min), and settling time (10 - 50 min). Turbidity increases by increasing initial turbidity and decreases by increasing the coagulant dosage, speed and time of 2nd step and settling time until the reaching to the optimum for them at the minimum turbidity, then any increasing of the coagulant dosage, speed and time of 2nd step will increase the turbidity, while any increasing of settling time will do no effect on turbidity. The optimum dosage for alum was 35, 40 and 50 ppm. While, for ferric chloride it was 15, 20 and 30 ppm and for polyelectrolyte 4, 8 and 10 ppm for 11.8, 30 and 100 NTU initial turbidity respectively. The optimum speed of 2nd step was 25 rpm for each of alum (35 ppm), ferric chloride (15 ppm) and polyelectrolyte (4 ppm). While the optimum time of 2nd step was 30 min for each of alum (35 ppm), ferric chloride (15 ppm) and polyelectrolyte (4 ppm) and settling time was 30 min for each of alum (35 ppm), ferric chloride (15 ppm) and polyelectrolyte (4 ppm). The second stage, natural gravity water filter or microfiltration MF was used to ensure that the particle size was in the demand limits (less than 10 ?m) and reduce the turbidity and the total suspended solids (TSS) to the demand limits (5 NTU and 3 - 3.5 mg/l). It was found that turbidity and TSS increases by increasing the inlet turbidity and TSS and the results was arranged progressively as the following : Natural gravity water filter ? 5 ?m MF ? 1 ?m MF. The final stage, nanofiltration NF membrane technology was used to remove sulphate from MOD. The variables studied were feed concentration (1800 - 9630 mg/l) and operating temperature (27 - 37 oC). Also concentrate recirculation was used to obtain high recovery percentage of water can be inject. It was found that product flow rate increases by increasing temperature and decreases by increasing salts concentration in feed. Also it was found that salts concentration in product increases by increasing feed concentration and temperature. Rejection percentages were (94.475 - 95.631 %), (88.088 - 90.714 %), (83.33 - 93.2 %), (85.116 - 92.727 %) and (65.385 - 72.727 %) for sulphate, total hardness (TH), Ca2+, Mg2+ and Cl - respectively and recovery percentage of product water was (11.429 - 38.143 %) for polyamide membrane (TFC). In the case of concentrate recirculation, feed concentration, permeate concentration and volume of permeate increases with increasing in operating time and 12.69 liter of water valid for injection in oil field was recovered from 25 liter feed after 180 minute.

تسريع انتاج الخل بالطريقة المستمرة == Speeding - Up The Production of Vinegar By Continuous Ferementation

اسم المؤلف: خليل عيدان حمد الدليمي

اسم المشرف: عبد القهار مهدي محمد السامرائي

الموضوع العام: الهندسة الكيمياوية

السنة: 2012

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: جامعة تكريت - كلية الهندسة - قسم الهندسة الكيمياوية

اللغة: العربية

مكان الجامعة: صلاح الدين

الصفحات الاولى:

معالجة عناصر الخارصين والنحاس والمنغنيز في مياه الفضلات الصناعية بطريقة الترسيب الكيمياوي == Treatment of Zinc ,Cupper And Manganese in Wastewater By Chemical Precipitation

اسم المؤلف: يوسف صالح عيسى

اسم المشرف: دريد فاضل احمد

الموضوع العام: الهندسة الكيمياوية

السنة: 2013

الموضوع الدقيق: الهندسة الكيمياوية

الدرجة: ماجستير

الجامعة: جامعة تكريت - كلية الهندسة - قسم الهندسة الكيمياوية

اللغة: العربية

مكان الجامعة: صلاح الدين

الصفحات الاولى:

المستخلص: تهدف هذه الدراسة الى ايجاد تاثير المعالجة الكيمياوية بطريقة الترسيب الكيمياوي على كفاءة ازالة العناصر الثقيلة في مياه الفضلات الصناعية المطروحة لتصل الى النهر بالتراكيز المسموح بها. تتم عملية الترسيب الكيمياوي بالسيطرة على الدالة الحامضية لمياه الفضلات ب | This study aims to find the effect of chemical treatment by chemical precipitation on the efficiency of removing heavy metals from wastewater to be poured back to the river. Chemical precipitation is done by controlling the (PH) of wastewater by adding a suitable hydroxide ,different hydroxides were used like the hydroxides of sodium ,calcium and potassium 0.05N each and sodium carbons 0.1N in removing heavy metals of wastewater. The study has taken prepared samples contain different concentrations of heavy metals ions like cupper 2,4 and 6 ppm zinc 5,10 and 15ppm and manganese 2,5,8 ppm Jar taste is used to show the chemical precipitation. Fast and slow mixing periods were written down to get the velocity gradient (G) and (GT) The used materials were highly efficient to remove the ions of metals. The removed amount of metals was measured by (AAS) Atomic Absorption spectroscopy. The paper has also studied the effective factors on the efficiency of precipitation like the (PH) is (8,9,10,11) and The precipitation time is (0.5,1,2,3)h.The result show that the best precipitation efficiency when an ion is used alone in the solution (PH) is (10,11) precipitation time 2h hydroxides precipitation (0.05N) it removes about 98% of cupper ions when sodium and calcium hydroxides are used ,more than 96,66% when the potassium hydroxide is used.a complete removing appears of manganese ions when the calcium hydroxide is used more than 90% when the potassium hydroxide is used.77% when the sodium hydroxide is used more than 98.4% of zinc ions removed when the sodium and calcium hydroxide is used 95.9% of zinc ions is removed when the sodium carbons are used the best treatment condition appear when the (PH) is (9 to10) and precipitation time is 2h when an ion is used alone in the solution 98% of cupper and zinc ions are removing 90% of manganese ions.When the ions are mixed in the solution the best removing efficiency appears when the (PH) is (9 to 11) and precepitition time is 2h when the hydroxides and carbons are used a complete removing of cupper ions 90% of zinc ions and more than 98.2% of manganese ions.The time of reaction to get 10.5 PH using hydroxides is (25 - 30) second when sodium carbon's are used the reaction time to get 8.5 is (50) second for cupper and zinc ,(25) second for manganese.The reaction is zero order when hydroxides are used and first order when carbons are used in treating heavy metals.