Abstract Recently more than 150 million tonnes of plastics were produced in the world. On the one hand, the consumption and production of polymers are increasing, on the other hand as landfill and incineration become more expensive and less accepted .The increasing amount of polymer wastes from them generates further mainly environmental problems. The recycling of plastic wastes is gaining increasing importance. Pyrolysis is one promising method for the treatment of mixed and contaminated plastic wastes. In this way the plastic wastes are converted into fuels or other valuable feedstock for the petrochemical industry. In present work catalytic cracking of waste plastics blend with HGO [Libyan gas oil supplied by the Zawia Oil Refinery Company boils in the range of 275-375Cº] was investigated using H-ZSM5and H-BETA. Reaction systems that were studied included high density polyethylene HDPE and polypropylene blend with HGO, reactions were carried out in one litre micro autoclave reactor under different conditions of weight, temperature and type of catalyst, The optimum conditions were 2.5% catalyst by weight of total feed stock, one hour, atmospheric presser and three temperatures selected 400Cº, 425Cº and 450Cº. The product distribution for the system [plastics and HGO] provided some good results high yield of liquid [gasoline] up to 210Cº, gases and small amount of heavy oils. Some analysis was used to qualify and quantify the product. The results from GC.MS analysis showed that the yield of gasoline (c5-c12) over H-ZSM5 higher than H-BETA. In case of 5%PP, 15%HDPE and 80%HGO over H-ZSM5 at 450Cº, 96% total conversion achieved. The result from TGA in the same case is 15% by weight. Also the theoretical calculations to quantify the produced gases after burring of waste plastic in rotary kiln reactor have been evaluated. it is found that the suitable ratio of CO:H2 to produce methanol is 7:1
بسمة محمود التونسي (2010)

دراسة ضمان التدفق هو احدي أهم العمليات التحليلية لمرور الزيت والغاز خلال الأنابيب والمعدات البتروكيميائية. هذه الدراسة تساعدنا فى تصميم وتشغيل وصيانة خطوط الزيت و الغازوخاصة الخطوط الموجودة في أعماق البحار. يعتبر الشمع والهيدريت من أهم المشاكل التى تواجه نقل الزيت والغاز عبر الأنابيب هذه المشاكل تكلف خسائر مالية كبيرة عن طريق اغلاق جزء من انابيب نقل الزيت والغاز. ولتجنب الوقوع فى خطر الهيدريت والشمع يجب ان تكون كل من درجة الحرارة والضغط بعيدة عن تكون الشمع والهيدريت. تضمنت هذه الدراسة تضمنت فحص تأتير كل من اللزوجة, متوسط الوزن الجزئ, نسبة الشمع, سمك العازل, الزمن ودرجة الحرارة الخارجية على ترسب الشمع على جدار أنابيب النقل. وكذلك قمنا بدراسة متى وأين يتكون الهيدريت باختيار زيوت وغازات مختلفة. من أهم النتائج التى تحصلنا عليها من خلال دراسة ترسب الشمع على الأنابيب وتكون الهيدريت كالأتي :أقل لزوجة في الزيوت الشمعية كانت عنده أعلى قيمة ترسب الشمغ علي الأنبوب .زيادة سمك العازل ودرجة الحرارة المحيطة تقلل ترسب الشمع على الأنابيب .زيادة زمن التشغيل تزيد من ترسب الشمع علي الأنابيب .دراسة تكون الهيدريت باستخدام برنامج كمبيوتر (HYSYS وPVTSIM) كانت النتائج المعملية قريبة من النتائج المعملية عند درجة حرارة وضغط منخفض. اضافة مواد كيميائية احدى الطرق التى تبعدنا عن خطر تكون الهيدريت. Abstract Flow assurance is the analysis of thermal, hydraulic and production chemistry issues during the flow of fluids through pipelines and process equipments in the oil and gas industry. These issues arise during the design, operation and maintenance of Gas/oil supply systems, which are often in deep water or challenging environments. Flow assurance studies are usually carried out at design and production stages to insure oil and gas flow in pipe lines and process equipment without any problems. Wax and hydrates are problems associated while gas and oil are transported. Wax deposition is a serious field problem encountered during crude oil production that causes plugging of pipe line, well tubing and process equipment. Wax crystals lead to oil high viscosity and decreased pumping capacity. Gas hydrates are a well-known problem in the oil and gas industry and cost millions of dollars in production and transmission pipelines. To prevent this problem, it is important to predict the temperature and pressure under which gas hydrates will form. This work aims to investigate the major flow assurance aspect (wax deposition and hydrates formation) in flow lines. This may include; Effect of oil viscosity, oil wax percent, average moleculer weight of oil, ambient temperature, insulation thickness and time duration on wax deposition rate in pipelines. In addition concerning hydrates, the main important issue is when and where hydrates will form in flow lines and gas pipelines. five different oils and different gases from literature where selected and utilized as working examples.The important results of wax deposition and hydrate formation are as the following: The lowest viscosity of five crude oils give us the maximum total volume deposition.Increasing of insulation thickness and ambient temperature causes decreasing wax layer deposition.Increasing of time duration causes increasing of wax layer thickness. Hydrate formation by using HYSYS and PVTSIM at law temperature and law pressure is closed to the hydrate formation by experimentally. Adding chemicals (inhibitors) saved the gas through a pipeline from the risk of hydrate formation. The obtained results show that wax deposition and hydrates formation can be predicted with good accuracy with computer soft ware.
المبروك فرحات المسلاتي (2014)

Abstract Matrix acidizing is a stimulation method commonly used to remove near wellbore damage and restore original formation permeability. It involves the injection of acid into formations at pressures below the fracture pressure. Acid flows down the well into the reservoir, and then reacts with the rock such that any near wellbore permeability damage created by meling or completion fluids can be removed and apparent permeability increased. A matrix acidizing treatment can be' applied to either a sandstone or a carbonate reservoir. Different acids are used because different minerals are involved in these treatments. Hydrochloric acid (HCI) is usually used in carbonate reservoirs to react with carbonates. Hydrofluoric acid (HF) or mixture of Hydrofluoric acid (HF) with Hydrochloric acid (HCI) is commonly used in sandstone porous media to react with silicates and feldspars in the rock. Since the mechanisms of acid reactions with these two types of rock are different, results of the treatments are different as well. In sandstone matrix acidizing, permeability increase behind the acid front is relatively homogeneous. The flow and reaction of acid in carbonate porous media results in the formation of highly conductive flow channels, commonly referred to as wormholes. In the present work we have studies the first study to test the optimal acid flux theory presented by Wang (1) with several independent sets of experimental data. The model was comparing with field data. The second study we use model presented by McCune and Fogler.(2) This previous studies on mathematical modeling of the chemical reactions between sandstone and mud acid. This model is lumped-parameter model. The lumped-parameter model simplifies the chemistry of the dissolution of sandstone minerals with mud acid. The models are compared with the experimental data at different flow rates.
عبد ربه ادريس بوسدرة (2010)