Well Production Performance Analysis for Shale Gas Reservoirs, Volume 66 presents tactics and discussions that are urgently needed by the petroleum community regarding unconventional oil and gas resources development and production. The book breaks down the mechanics of shale gas reservoirs and the use of mathematical models to analyze their performance. Features an in-depth analysis of shale gas horizontal fractured wells and how they differ from their conventional counterparts Includes detailed information on the testing of fractured horizontal wells before and after fracturing Offers in-depth analysis of numerical simulation and the importance of this tool for the development of shale gas reservoirs
To obtain better well performance and improved production from shale gas reservoirs, it is important to understand the behavior of shale gas wells and to identify different flow regions in them over a period of time. It is also important to understand best fracture and stimulation practice to increase productivity of wells. These objectives require that accurate production analysis be performed. For accurate production analysis, it is important to analyze the production behavior of wells, and field production data should be interpreted in such a way that it will identify well parameters. This can be done by performing a detailed analysis on a number of wells over whole reservoirs. This study is an approach that will lead to identifying different flow regions in shale gas wells that include linear and bilinear flow. Important field parameters can be calculated from those observations to help improve future performance. The detailed plots of several wells in this study show some good numbers for linear and bilinear flow, and some unique observations were made. The purpose of this work is to also manage the large amount of data in such a way that they can be used with ease for future studies. A program was developed to automate the analysis and generation of different plots. The program can also be used to perform the simple calculations to calculate different parameters. The goal was to develop a friendly user interface that would facilitate reservoir analysis. Examples were shown for each flow period, i.e. linear and bilinear flow. Different plots were generated (e.g; Bob Plot (square root of time plot) and Fourth Root of Time Plot, that will help in measuring slopes and thus reservoir parameters such as fracture permeability and drainage area. Different unique cases were also observed that show a different behavior of well in one type of plot from another.
Natural gas is playing an increasing role in meeting world energy demands because of its abundance, versatility, and its clean burning nature. As a result, lots of new gas exploration, field development and production activities are under way, especially in places where natural gas until recently was labeled as “stranded . Because a significant portion of natural gas reserves worldwide are located across bodies of water, gas transportation in the form of LNG or CNG becomes an issue as well. Finally natural gas is viewed in comparison to the recently touted alternatives. Therefore, there is a need to have a book covering all the unique aspects and challenges related to natural gas from the upstream to midstream and downstream. All these new issues have not been addressed in depth in any existing book. To bridge the gap, Xiuli Wang and Michael Economides have written a new book called Advanced Natural Gas Engineering. This book will serve as a reference for all engineers and professionals in the energy business. It can also be a textbook for students in petroleum and chemical engineering curricula and in training departments for a large group of companies.
In recent years, production decline-curve analysis has become the most widely used tool in the industry for oil and gas reservoir production analysis. However, most curve analysis is done by computer today, promoting a "black-box" approach to engineering and leaving engineers with little background in the fundamentals of decline analysis. Advanced Production Decline Analysis and Application starts from the basic concept of advanced production decline analysis, and thoroughly discusses several decline methods, such as Arps, Fetkovich, Blasingame, Agarwal-Gardner, NPI, transient, long linear flow, and FMB. A practical systematic introduction to each method helps the reservoir engineer understand the physical and mathematical models, solve the type curves and match up analysis, analyze the processes and examples, and reconstruct all the examples by hand, giving way to master the fundamentals behind the software. An appendix explains the nomenclature and major equations, and as an added bonus, online computer programs are available for download. Understand the most comprehensive and current list of decline methods, including Arps, Fetkovich, Blasingame, and Agarwal-Gardner Gain expert knowledge with principles, processes, real-world cases and field examples Includes online downloadable computer programs on Blasingame decline type curves and normalized pseudo-pressure of gas wells
"Shale gas resource plays a significant role in energy supply worldwide. For economic production of shale gas, technologies of horizontal well and hydraulic fracturing are used for shale gas reservoirs. Therefore, the productivity of the shale gas reservoirs will be influenced by both reservoir condition, and hydraulic fracture properties. In this thesis, parameters that will influence shale gas production were classified into two categories: reservoir properties and hydraulic fracture properties. Published shale gas simulation studies were surveyed for determining the typical ranges of those properties. CMG-GEM was employed to finish the reservoir simulation work, and CMG-CMOST was used to complete the sensitivity analysis work. A three dimensional single phase dual-permeability shale gas reservoir model was created. Three flow mechanisms (Darcy flow, Non-Darcy flow, and Gas diffusion) as well as gas adsorption and desorption mechanism were considered in this model. Sensitivity checks for each parameter were performed to analyze the effect of factors to forecast the production of shale gas reservoir. Influences of reservoir and hydraulic fracture parameters for different time periods were quantified by simulation of 1 yr., 5 yr., 10 yr., and 20 yr. production"--Abstract, page iii.
Liquid loading can reduce production and shorten the lifecycle of a well costing a company millions in revenue. A handy guide on the latest techniques, equipment, and chemicals used in de-watering gas wells, Gas Well Deliquification, 2nd Edition continues to be the engineer’s choice for recognizing and minimizing the effects of liquid loading. The 2nd Edition serves as a guide discussing the most frequently used methods and tools used to diagnose liquid loading problems and reduce the detrimental effects of liquid loading on gas production. With new extensive chapters on Coal Bed Methane and Production this is the essential reference for operating engineers, reservoir engineers, consulting engineers and service companies who supply gas well equipment. It provides managers with a comprehensive look into the methods of successful Production Automation as well as tools for the profitable use, production and supervision of coal bed gases. Turnkey solutions for the problems of liquid loading interference Based on decades of practical, easy to use methods of de-watering gas wells Expands on the 1st edition’s useful reference with new methods for utilizing Production Automation and managing Coal Bed Methane
Unconventional tight gas and shale gas are the largest and fastest growing natural gas supply in the US. Natural gas produced from tight gas and shale gas reservoirs accounts for 60% of U.S. natural gas production in 2011. This number is expected to increase to 73% in 2040 (EIA, 2013). The lack of understanding and the lack of tools that can be applied to these unconventional plays are the major challenges. In unconventional tight gas and shale gas, the conventional reservoir engineering tools have been proven to be unsuccessful because they fail to capture the large differences in physical properties which heavily impact the production behaviors. The main differences include the ultra-low permeability of the formation, presence of adsorbed phase, and the need for multi-stage hydraulically fractured horizontal well completion to create massive flow area.This study aims to develop new reservoir engineering analysis techniques which fully apply for unconventional tight gas and shale gas reservoirs. The new techniques should be able to capture the reservoir responses that are characterized by the transient flow regime and the multi-mechanistic flow in ultra-low permeability formations, the complex flow pattern from hydraulic fracture completion, and the natural gas desorption. We focus on formulating the fundamental, physics-based governing equation for these tight gas and shale gas reservoirs, as well as the long-term analysis and prediction tools that can capture their physical properties. The research applies new promising tools, a density approach, which was proposed to the industry by our research group. In the density method, gas diffusivity equation will be solved in a density-based form, and effects of reservoir depletion on fluid properties are captured through dimensionless variable, [lambda]-[beta]. The density method has been proven to be a reliable production data analysis tool applicable to conventional gas reservoirs produced under constant flowing pressure, constant flow rate, variable pressure/rate constraint as well as in reservoirs with significant rock compressibility. In this thesis, we prove that density-based technique can be further extended to analyze production data from i) gas linear and fractal flow under boundary dominating condition, ii) gas radial, linear, and fractal flow with significant transient flow period, and iii) gas flow under slippage and desorption effects. We demonstrate that [lambda]-[beta] can effectively quantify effects of depletion on gas properties in reservoirs with linear, radial, and fractal flow. We also show how to incorporate slippage and desorption effects as well as transient flow effect by properly modified definitions of [lambda]-[beta]. Based on these results, we are able to show that the density-based production analysis tools, originally developed for conventional gas reservoirs under boundary dominated radial flow, can be applied to predict and analyze production from unconventional gas reservoirs. In addition, we are able to use these density-based tools to analyze the impact of flow geometries on production decline behavior of gas wells.
Shale Gas and Tight Oil Reservoir Simulation delivers the latest research and applications used to better manage and interpret simulating production from shale gas and tight oil reservoirs. Starting with basic fundamentals, the book then includes real field data that will not only generate reliable reserve estimation, but also predict the effective range of reservoir and fracture properties through multiple history matching solutions. Also included are new insights into the numerical modelling of CO2 injection for enhanced oil recovery in tight oil reservoirs. This information is critical for a better understanding of the impacts of key reservoir properties and complex fractures. Models the well performance of shale gas and tight oil reservoirs with complex fracture geometries Teaches how to perform sensitivity studies, history matching, production forecasts, and economic optimization for shale-gas and tight-oil reservoirs Helps readers investigate data mining techniques, including the introduction of nonparametric smoothing models
With increase of interest in exploiting shale gas/oil reservoirs with multiple stage fractured horizontal wells, complexity of production analysis and reservoir description have also increased. Different methods and models were used throughout the years to analyze these wells, such as using analytical solutions and simulation techniques. The analytical methods are more popular because they are faster and more accurate. The main objective of this paper is to present and demonstrate type curves for production data analysis of shale gas/oil wells using a Dual Porosity model. Production data of horizontally drilled shale gas/oil wells have been matched with developed type curves which vary with effective parameters. Once a good match is obtained, the well dual porosity parameters can be calculated. A computer program was developed for more simplified matching process and more accurate results. As an objective of this thesis, a type curve analytical method was presented with its application to field data. The results show a good match with the synthetic and field cases. The calculated parameters are close to those used on the synthetic models and field cases.
This book addresses the problems involved in the modelling and simulation of shale gas reservoirs, and details recent advances in the field. It discusses various modelling and simulation challenges, such as the complexity of fracture networks, adsorption phenomena, non-Darcy flow, and natural fracture networks, presenting the latest findings in these areas. It also discusses the difficulties of developing shale gas models, and compares analytical modelling and numerical simulations of shale gas reservoirs with those of conventional reservoirs. Offering a comprehensive review of the state-of-the-art in developing shale gas models and simulators in the upstream oil industry, it allows readers to gain a better understanding of these reservoirs and encourages more systematic research on efficient exploitation of shale gas plays. It is a valuable resource for researchers interested in the modelling of unconventional reservoirs and graduate students studying reservoir engineering. It is also of interest to practising reservoir and production engineers.
