Novel Model For Simulating Performance Of Twin Screw Multiphase Pumps Capable Of Handling high Gas Volume Fraction (GVF) With Nodal Analysis For Reservoir/well/pump Interactions.

For the last decades, the term artificial lift has mainly referred to the conventional techniques of downhole pumping systems (e.g., electrical submersible, sucker rod, progressing cavity, and others) and gas lift. Today, a more comprehensive definition is becoming evident, a definition which matches all the major changes happening in the oil & gas industry. Accordingly, artificial lift is not limited anymore to techniques conducted in the wellbore, however instead techniques used throughout the whole production system to “lift” the produced fluids towards their final destination should be included. All petroleum wells’ production lives are brought to an end when the downhole reservoir pressure cannot deliver fluids traveling up to the processing facility. Numerous advanced technological approaches were practically implemented at many fields to extend field exploitation which are approaching the end of their lives. One such technique is to introduce Multiphase Pumps (MPP), which are based on a technique used to add energy to the unprocessed crude from the well to transport the oil / gas / water mixtures to the CPF over several distances without the need for preliminary separation or any well interventions to install downhole equipment like other conventional artificial lift techniques and with maintaining a more environmental friendly performance as gas flaring is no longer required and oil spills are avoided. This thesis is aimed at addressing the difficulties in field development studies involved in the evaluation of multiphase Pumps. These problems are related to uncertainty about the approach adopted to test the pump. Minimal information about the multi-phase pump performance results in difficulty for any new Pump model to evaluate its applicability. As the performance curve of a pump is dependent on the inlet fluid properties, such as fluid inlet pressure, temperature, water cut, gas volume fraction (GVF), etc. Therefore, the correct prediction requires the performance of the pump to be evaluated for each fluid property change throughout the field life. As well, a complete nodal analysis study is performed through industrial software package to study the MPP effect on the production system performance and quantify the production gains after introducing the MPP into the system. The results of this study clearly demonstrates the tremendous effect of multiphase pumps in reactivating and enhancing production from dying wells or brown fields providing a cost effective solution rather than conventional methods. Some operation challenges are very important to be considered especially when operating the pump at high GVF above 90% as a liquid recirculation system is required coupled with precise evaluation of system parameters to avoid gas flashing within the pump leading to reduction of pump efficiency, and with respect to solids handling measures upstream of the pump as well. Nevertheless, multiphase pumping proves its efficiency in de-liquification of liquid loaded gas wells which ceases to flow before pump introduction. Lastly, a novel model is produced to provide a detailed selection criteria for both pumps selected from different available models from different international vendors based on each production system parameters, and well selection plan to best choose well candidates to provide the optimum effect of the multiphase pump.