Oil/gas reservoir engineering

However, the majority of scientific publications in these researches and applications are on domestic Chinese journals that cannot be readily reached by international readers. In order to compensate this shortcoming, this review presents systematically the scope and spectra of the research and applications in the field of coupled T-H-M-C processes published on Chinese journals, concentrating mainly on the fundamental studies and applications in oil/gas reservoir engineering, coal mining, engineering in cold regions and water resources engineering. The... 

In gas reservoir engineering, the gas expansion factor, E, is commonly used. However, in oil reservoir engineering it is often more convenient to refer to the gas formation volume factor which is the reciprocal E, and is expressed in units of scf/stb (using field units). The reason for this will become apparent in Section 8. 

Jacqmin, D. 1990. Interaction of natural convection and gravity segregation in oil/gas reservoirs. Society of Petroleum Engineers Re.vervoir Engineering, May 1990, 233-238. 

AbStrSCt Theoretical models of coupled T-H-M-C processes of geological media and the associated numerical solutions have become an attractive research focus in geomechanics and related fields in China. This paper provides a systematic overview of the past progress in the fundamental studies of the coupled THM models and numerical methods, and their applications in the fields of oil/gas reservoir, coal mining, and water resources engineering works. The key areas of weakness in research in this field are also outlined and possible directions for the future development are discussed. 

Reservoir engineers describe the relationship between the volume of fluids produced, the compressibility of the fluids and the reservoir pressure using material balance techniques. This approach treats the reservoir system like a tank, filled with oil, water, gas, and reservoir rock in the appropriate volumes, but without regard to the distribution of the fluids (i.e. the detailed movement of fluids inside the system). Material balance uses the PVT properties of the fluids described in Section 5.2.6, and accounts for the variations of fluid properties with pressure. The technique is firstly useful in predicting how reservoir pressure will respond to production. Secondly, material balance can be used to reduce uncertainty in volumetries by measuring reservoir pressure and cumulative production during the producing phase of the field life. An example of the simplest material balance equation for an oil reservoir above the bubble point will be shown In the next section. 

The facilities designer combines the reservoir/petroleum engineer s estimate of oil/gas/water production (Fig. 1) with overlay timing logic. 

There are five types of reservoir fluids. These are usually called black oil, volatile oil, retrograde gas, wet gas, and dry gas. The five types of reservoir fluids have been defined because each requires different approaches by reservoir engineers and production engineers. 

Do not attempt to compare fluid types as defined here with the reservoir descriptions as defined by the state regulatory agencies which have jurisdiction over the petroleum industry. The legal and regulatory definitions of oil, crude oil, gas, natural gas, condensate, etc., usually do not bear any relationship to the engineering definitions given here. In fact, the regulatory definitions are often contradictory. 

We now turn to black oils. We consider those physical properties which are required for the reservoir engineering calculations known as material balance calculations. These properties are formation volume factor of oil, solution gas-oil ratio, total formation volume factor, coefficient of isothermal compressibility, and oil viscosity. Also, interfa-cial tension is discussed. 

This assumption implies that gas and liquid in the reservoir separate as the gas is formed. One can argue that this is not strictly true. However, a laboratory process that more accurately represents the production process would be complicated and expensive and would require excessively large samples of reservoir liquids. Experience has shown that black oil properties calculated under this assumption are sufficiently accurate for reservoir engineering calculations. 

Energy specialists and reservoir engineers in the United States and several other countries use proved reserves to predict the amounts of coal, oil, and natural gas that can be produced and marketed. Proved reserves are defined... 

This paper presents a mass balance approach that directly integrates dynamic elements of the total petroleum system with all static reservoir engineering, geochemical and petrophysical components. This prospect evaluation technique provides an independent estimate of hydrocarbon resource-in-place for comparison with that computed from the conventional reservoir engineering approach. In addition, the mass balance approach may be used to quantify the resource lost from the system and quantify the reservoir trapping efficiency. Although presented in the context of a basin-centred gas accumulation, the methodology with some modifications is also applicable to the evaluation of any conventional oil or gas exploration prospect. 

There has been very little progress in calculating the flow of water, oil, or gas in naturally occurring rocks without experimental test because naturally occurring rocks are much, much less uniform than the beds of uniform sized spheres described by Fig. 12.4, Thus, in the study of groundwater movement and in petroleum reservoir engineering, it is customary to simplify Eq. 12.13 to... 

Drilling and production through hydrate formations above oil and gas reservoirs can cause dissociation and well blowouts. Similarly, the possible instability of the sea floor sediments over hydrate deposits where oil and gas is extracted raises concerns over the collapse and loss of engineering structures. 

This relation shows that addition of hexane to CH4 increases the magnitude of y of the mixture. In fact, one can estimate the concentration of hexane in CH4 by using Equation 1.57. This has much interest in oil reservoir engineering operations where one finds CH4 in the crude oil. Experiments show that addition of a gas to a liquid will always decrease the value of y of the mixture. 

Gas Reservoirs Heavy Oil Hydrocarbons Petroleum Engineering Petroleum Geology Petroleum Industry and Trade Petroleum Pipelines Petroleum Products Petroleum Refineries Petroleum Refining Petroleum Reserves Petroleum, Synthetic Secondary Recovery of Oil Thermal Oil Recovery... 

Ahmed, T. 2010. Reservoir Engineering Elandbook, 4th ed. Boston Gulf Professional Publishers. This book explains the fundamentals of reservoir engineering and their practical applications in conducting a comprehensive field study (from Preface, p. xv). Divided into 17 chapters., the coverage includes reservoir fluid behavior and properties, fundamentals of reservoir fluid flow, oil and gas well performance, oil recovery mechanisms, and methods for the prediction of oil reservoir performance. 

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