Abstract Here asphaltene precipitation in petroleum reservoirs during natural depletion and miscible gas injection is modeled for two distinct and new methods (polymer solution and Scott-Magat theory). The first model is based on the polymer solution theory, which is a combination of Miller's combinatorial term with a modified residual term of the original Flory-Huggins theory. The second one is based on the Scott Magat theory to represent solid-liquid equilibria. The models has also been coupled with Peng Robinson equation of state (PR EOS) to describe the phase behavior of asphaltene compounds in crude oil and predict the amount of asphaltene precipitation during injection of carbon dioxide for the miscible displacement of asphaltic crudes. The model treats asphaltene within crude oil as a single pseudocomponent represented by an average molecular weight and molar volume and solubility parameter . The results of both models show an acceptable and good agreement between the real data (field and experimental) and those of the models. As it can be seen from the obtained results of those of the two models, it seems that application of the lattice or polymer solution theories (based on The Miller's combinatorial term) could give better results that are more close to real data.
وداد بلعيد حميدات (2009)

Abstract Water contamination is one of the major problems which the world is facing today. Water contamination not only effect environment and human health, but it has also impacts on economic and social costs. There are various ways used commercially and non- commercially to fight this problem which is advancing day by day due to technological progress There are many methods used for wastewater treatment, among these methods, the use of biological filters " trickling filter ", which depends on The basic idea is to get a larger surface area to get a better handle on the percentage. A composite media is used to replace the conventional stone in order to improve wastewater treatment in this thesis. The aim of this thesis to improve the performance of biological filters using nanotechnology, where to enhancing polymer media in biological and reinforced polypropylene by carbon fiber filters and talc by using electro spinning technology to produce the reinforced fiber that outlet from extruder. Design and simulate the extruder / die characteristics and studying The drag flow and pressure flow were then extracted from the screw parameters which lead into the calculation of the operation point and the operating pressure for the die. Also studying the effect of pressure and viscosity. Calculation of , and extruder characteristic is performed in order to allocate the operating point of the extruder.Two brand of carbon fiber are used in this thesis. The chapter type is at A tensile strength of 800 MN/m2. is selected. The operating pressure of the extruder is found to vary form 29.8 to 38.95 MN/m2 at an operating flow rate of 1.52*10-5 m3/sec. depending on the percentage of carbon fiber used in the blend.
محمود عيسى الفاما (2015)

Abstract This study is to develop the specifications of the present cement products so as to comply with the quality and quantities requirements of the local market. The subject of this thesis is to present the results of a series of laboratory trials on a number of raw material mixtures prepared to produce moderate and high sulfate resistance cement at EL- Mergheb cement factory which currently produces ordinary Portland cement. At first, six different raw material sample mixtures were prepared from marlstone,marl and iron ore. The clinker (cement ) produced from these samples was within the moderate sulfate resistance cement ( MSRC ) specifications which mainly requires the tri calcium aluminate (C3A) to be less than 8 % by weight. The trial runs on other three raw material samples made that from mixing marlstone , clay , and iron ore produced clinker specifications that were out of those for MSRC namely, C3A is greater than 8 % . This means that the addition of clay to the raw mix prevents the production of cement with MSRC specifications. This was due to the high percentage of Al2O3 in the clay . The specifications of the clinker products based on these results , MSRC was successfully produced at the factory from raw material mixtures ( marlstone, marl and iron ore ) without any clay addition . Finally three raw mix samples were prepared from marlstone, marl, iron ore, and sand and tested in the laboratory to explore the possibility of producing high sulfate resistance cement ( HSRC) which requires C3A to be less than 5 % . The results of these laboratory trials showed that when the sand in the raw mix is kept under 1.80 % , the produced clinker specifications are within those of HSRC. The permission to carry out these trials in the factory is underway. The expected economic benefits from producing both MSRC and HSRC is highly feasible. Both types will be sold in local market without any additional operating or capital costs .
صالح محمد صالح (2013)