Mathematical Model for Flow of Pseudoplastic Fluids in Porous Media

A non-linear partial differential equation for the flow of all types of pseudoplastic fluids in porous media was derived. The rheological characteristics of the pseudoplastic fluids were described by the generalized approach developed by Metzner and Reed. A linear form of the equation developed was derived and solved. Analytical solutions were obtained for a constant injection rate into an infinite reservoir.The validity of the present analysis was verified by comparing the pressures calculated from the developed equation with published data. The equation deduced provides an accurate prediction for pressure distributions

Rheological Behavior of Saudi Crude Oils

The wide changes in temperature during summer and winter in Saudi Arabia may cause changes in Saudi crude oil properties. Since crude oil behavior has a significant importance for pipeline design calculations and storage, rheological behavior of Arab light, Arab Berri and Arab heavy crudes were determined at different temperatures (10-70°C). Viscosity-temperature relationships were also studied. The results indicated that crude oil properties were changed from Newtonian to non-Newtonian at low temperatures while Arab Bern crude behaved non-Newtonian at both low and high temperatures

Mathematical Model for Flow of Pseudoplastic Fluids in Porous Media

A non-linear partial differential equation for the flow of all types of pseudoplastic fluids in porous media was derived. The rheological characteristics of the pseudoplastic fluids were described by the generalized approach developed by Metzner and Reed. A linear form of the equation developed was derived and solved. Analytical solutions were obtained for a constant injection rate into an infinite reservoir.The validity of the present analysis was verified by comparing the pressures calculated from the developed equation with published data. The equation deduced provides an accurate prediction for pressure distributions

Friction factors for yieldless fluids in turbulent pipe flow in turbulent pipe flow

A new equation relating the friction factor to the generalized Reynolds number and rheological characteristics of non-Newtonian yield less fluids was developed under turbuJentpipeflow conditions. The rheological behaviour of yield lessfluids was' described by the generalized approach developed by Metzner and Reed. Statistical error analysis were used to determine the accuracy of the developed equation. To verify the validity of the present analysis,a comparison was' made between published experimental frictionfactors and those calculated from the developed equation, Dodge and Metzner, and Desouky and El-Emam correlations.A comparison was' also made between field measurements and calculated ones. The results showed that the developed equation provided a more accurate estimation of friction factor

Using Local Gravel to Control Sand Production in a Saudi Oil Field

Sand production from oil and gas reservoirs is most commonly associated with unconsolidated and poorly cemented sandstones. Sand production problems are encountered throughout the world and recently are detected in Saudi Arabia. Several techniques could be used to minimize sand production such as drawdown control, installing screen liners, applying resin consolidation, gravel packing, etc. This work was conducted to investigate the possibility of using gravel packs made from gravel deposited in the central province of Saudi Arabia. Optimum gravel size, shape, crushing resistance and solubility in acids were tested. The results of the above analysis showed that the selected Saudi gravel properties meet the recommended API requirements. Furthermore, a physical model has been constructed to simulate sand control process. This model was used to study the effect of drawdown pressure, confining pressure and gravel-pack thickness on rate of fluids and sand production in a Saudi oil field. The experimental results showed that sand and fluid production are affected by the gravel pack thickness, drawdown pressure and confining pressure. Therefore, it is recommended to utilize the tested Saudi gravel in sand control applications after performing an economical feasibility study

Using Local Gravel to Control Sand Production in a Saudi Oil Field

Sand production from oil and gas reservoirs is most commonly associated with unconsolidated and poorly cemented sandstones. Sand production problems are encountered throughout the world and recently are detected in Saudi Arabia. Several techniques could be used to minimize sand production such as drawdown control, installing screen liners, applying resin consolidation, gravel packing, etc. This work was conducted to investigate the possibility of using gravel packs made from gravel deposited in the central province of Saudi Arabia. Optimum gravel size, shape, crushing resistance and solubility in acids were tested. The results of the above analysis showed that the selected Saudi gravel properties meet the recommended API requirements. Furthermore, a physical model has been constructed to simulate sand control process. This model was used to study the effect of drawdown pressure, confining pressure and gravel-pack thickness on rate of fluids and sand production in a Saudi oil field. The experimental results showed that sand and fluid production are affected by the gravel pack thickness, drawdown pressure and confining pressure. Therefore, it is recommended to utilize the tested Saudi gravel in sand control applications after performing an economical feasibility study

Optimizing the Production of LNG and NGL from Arab Crudes and Wet Gases

Natural Gas Liquids (NGL) refer to a mixture of gases that consist mostly of ethane, propane, butane and pentane. The other term which closely related to NGL is Liquified Natural Gas (LNG) which refers to methane and traces of ethane. These products can be extracted by multi-stages of compression and cooling. In addition of being the main feedstock of any petrochemical industry, NGL and LNG are used widely in the industrialized countries as a major source of energy. It is expected that their future role in both the international energy market and the petrochemical industry will continue its historical gradual growing trend.This paper presents the mathematical formulation of an economic model that was developed to optimize the production of LNG and NGL. The objective function of the model is to maximize the net cash flow return of selling LNG and NGL. The explanatory variables of the model are LNG and NGL volumes and prices, oil volume and prices, the initial costs of separators, chillers, demethanizer, compressor, partial condenser and boiler, the running cost which includes cost of refrigerants, cost of steam and other continuous operating and transportion cost. The developed model should be utilized as a useful tool to help the design of an efficient processing of natural gases. A great deal of the unlimited what if questions can be answered using this model. This paper also presents a flow sheet of the natural gas processing model. Each section of the proposed production system is presented schematically. The mathematical formulation of the computation techniques used in each section are given along with all the equation derivations