ABSTRACT Comparative economic analysis of the use of compressed natural gas (CNG) and the use of AGO for power generation was presented. The data for costs of constructing and running CNG-powered vehicles were obtained for the study. Separate economic analyses of running the CNG-powered vehicles and running AGO vehicles were performed. The initial capital cost for CNG project amounted to N4.31 million and that for diesel was N3.60 million while the annual operating cost for CNG is N1.47 mill...
ABSTRACT Flow assurance is the efficient and successful flow of fluids in pipes. Some of the flow assurance challenges that can be encountered include hydrate formation, which is prevalent offshore, sand deposition, wax precipitation, scale deposits, or emulsion problems. In onshore production facilities in the Niger delta, wax deposition is the major challenge to efficient fluid flow. Consequently, it has been the focus of research to proffer effective predictive control measures to a probl...
ABSTRACT With the ever increasing need to optimize production, the accurate understanding of the mechanics of multi-phase flow and its effect on the pressure drop along the oil-well flow string is becoming more pertinent. The efficient design of gas-lift pump, electric submersible pumps, separators, flow strings and other production equipment depends on the accurate prediction of the pressure drop along the flow pipe. Pressure is the energy of the reservoir/well and it is crucial to understa...
ABSTRACT This research describes the application of a production economic approach which attempts to quantity stimulation treatments performed on different wells undergoing a decline phase in their production and to obtain based on the output from the model the best time during the declining phase of the wells to initiate stimulation treatments. Two different production decline models were considered in this work i.e., the exponential model and the hyperbolic model. The optimization models w...
ABSTRACT Rate decline analysis is an essential tool in predicting reservoir performance and formation property estimation. The use of historical production data to predict future performance is the focus of the empirical domain of decline analysis while the theoretical domain focuses on the use of such data to estimate formation properties. A number of attempts have been made to establish the theories of rate decline in solution gas drive reservoirs. Such attempts have established the theore...
ABSTRACT One of the ways of maximizing recovery from a reservoir is by drilling infill wells. Infill well placement is challenging because many well scenarios must be evaluated when undertaking the optimization program and very often, the variables that affect reservoir performance are nonlinearly correlated with some degree of uncertainty. Resultantly, the use of stochastic search algorithms has gained wide acceptance in solving problems associated with well placement. This research seeks t...
Abstract Hydraulic fracturing has been an effective technique to stimulate damaged wells or wells producing from low-permeability formation. It has been established that the orientation of a hydraulic fracture is perpendicular to the direction of the least principal stress in the formation. Thus, most pressure transient analysis techniques are based on the assumption that the fracture is vertical. However, it is now generally agreed that the direction of the least principal stress is not alw...
ABSTRACT Surge and swab pressure computation is very important in drilling hydraulics. Most blowout problem in oil wells have been as a result of surge and swab pressures developed from running or pulling of tubular goods in liquid-filled bore hole. Excessive surge pressures can fracture the geological formation, while excessive swab can result in blowouts. In this work the analysis of steady state, laminar couette flow of non-Newtonian yield power law drilling fluid model (Herschel-Bulkley)...
ABSTRACT Appropriate selection of rheological models is important for hydraulic calculations of pressure loss prediction and hole cleaning efficiency of drilling fluids. Power law, Bingham-Plastic HerschelBulkley models are the conventional fluid models used in the oilfield. However, there are other models that have been proposed in literature which are under / or not utilized in the petroleum industry. The primary objective of this study is to recommend a rheological model that best-fits th...
ABSTRACT Techniques in Geostatistics are increasingly being used to generate reservoir models and quantify uncertainty in reservoir properties. This is achieved through the construction of multiple realizations to capture the physically significant features in the reservoir. However, only a limited number of these realizations are required for complex fluid flow simulation to predict reservoir future performance. Therefore, there is the need to adequately rank and select a few of the realiza...
ABSTRACT The effect of liquid flow rate, pipe size (diameter) and pipe orientation (inclination) on liquid hold-up was investigated. Liquid flow rate between 500 STB/day and 5000 STB/day was studied. An oil of 25˚API at an average temperature of 175˚F, a gas gravity of 0.65, water cut of 25% with water gravity of 1.07 and containing no free gas was used in this study. The correlations given by Standing, Culberson and Maketta, Vasquez, Dodson and Standing, Papay, Beggs and Robinson, and Lee...
ABSTRACT In the past years, several researches have been done on gas-condensate reservoir recovery performance using fully compositional simulators. Fully compositional simulators are more expensive, time consuming and have complex data requirement as compared to limited compositional reservoir simulators. An alternative method of evaluating gas condensate reservoir recovery has been considered in this research; it is four-component limited compositional reservoir simulator. The limited comp...
ABSTRACT Every simulation study is a unique process, starting from the geological model and reservoir description to the final analysis of recovery factor optimizations. In petroleum engineering area, numerical reservoir simulators are often employed to obtained meaningful and reliable solutions for most actual cases due to extreme complexity of reservoir systems. In this work, a three-dimensional numerical reservoir simulator is developed for expansiondrive reservoirs. The governing equatio...
ABSTRACT The scope of this work was to make detailed analysis of phase distribution in a horizontal pipe. This detailed analysis has been successfully carried out. Data obtained from wire mesh sensor (WMS) were used for the analyses. The operating fluid considered was an air/silicone oil mixture within a 6 m horizontal pipe with internal diameter of 0.067 m. The gas superficial velocities considered spans from 0.047 to 4.727 m/s, whilst liquid superficial velocities ranged from 0.047 to 0.47...
ABSTRACT Oil deposits are often found in association with a communicating gas or water zone. The production of the oil often leads to the coning of water or gas. This dynamic interaction can be captured by a properly detailed reservoir simulation, which unfortunately may not always be practical. To brigde the gap, researchers over the years have developed both analytical and empirical methods of modelling gas and water coning in oil reservoir. The fundamental questions have always been: what...