2.6 Productivity Index The productivity index is a measure of the well potential or ability to produce and is a commonly measured well property.The symbol J is commonly used to express the productivity index; as well as, being the preferred symbol by the Society of Petroleum Engineers. The productivity index of a well is a measure of the production rate achievable under a given drawdown pressure, which is the difference between the average reservoir pressure and the flowing bottom hole pressure. Defined as the flow rate per unit pressure drop, the productivity index gives an indication of the production potential of a well.
From the bpss equation above:
Therefore: From a reservoir point of view, well management
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Standing was one of the first to address the prediction of future well performance from IPRs. He used Vogel’s IPR with a modified multiphase productivity index to relate current well performance to future performance. Unfortunately, his relationship requires knowledge of fluid properties and relative permeability behavior. This makes Standing’s method difficult to use because one must estimate saturation, relative permeability, and fluid properties at a future reservoir …show more content…
2.5 Material Balance Equation (MBE) For gas, the MBE is defined as the relationship between the original gas in place, initial pressure (pi), cumulative gas production, and the current average reservoir pressure. The basis of the MBE for gas flow is the volumetric balance of all the fluids at a given time. The following equation proposed by Ramagost and Farshad (1981) is used to calculate the average reservoir pressure for gas systems. This equation considers that gas is the only mobile phase in the presence of residual fluid saturations (oil and water) in a compressible formation.
Note that this equation is only valid when the term ce(pi – p) < 1
For oil and water The MBE is defined as the relationship between the original fluid in place, initial pressure (pi), cumulative fluid production, total system compressibility (ct), and current average reservoir pressure. The following equation for liquid flow is based on the definition of total compressibility (ct) at a given time. This equation considers the selected fluid (oil or water) as the only mobile phase in the presence of residual fluid saturations, if present, in a compressible
Gas in shale formations are“low in permeability,” making it very tedious to extract, but with the increase in technological knowledge in fracking and horizontally drilling into shale beds, the vast reserves of natural gas resource could be extracted (4). Fracking is a large industrial operation that boost the “productivity of a oil or gas well” (5). It is a process by which, under very high pressure, a mixture of water, chemicals, and sand, are pumped into shale formations that causes fractures in the rocks to open wider or create new fractures that would allow otherwise trapped oil and gas to flow into the wells (6).
In classical fluid dynamics, the Navier-Stokes equations for incompressible viscous fluids and its special (limiting) case the Euler equations for inviscid fluids are sets of non-linear partial differential equations that describes the spatiotemporal evolution of a fluid (gas). Both equations are derived from conservative principles and they model the behavior of some macroscopic variables namely: mass density, velocity and temperature.
The two dominant physical properties of oil and gas that enhance their movement through subsurface substance are their relative immiscibility in water and their lower density than water which causes their buoyancy. Buoyancy of the hydrocarbons occurs because of differences in densities of respective fluids while transcend via the oil and gas reservoir is a stimuli which creates differential pressures that exist in a reservoir bed.
In order to ensure enough organic matter and plenty of space to form commercial shale gas reservoirs, the effective thickness of shale rock is required. Shale gas reservoir’s thickness controls of the economic benefits of shale gas reservoirs. The larger the effective thickness, especially the larger continuous effective thickness, the more the total amount of organic matter, the higher the degree of enrichment of shale gas. The limitation of shale thickness gas can be reduced with maturity of organic carbon content increasing.
The main aim of reservoir characterization is to build an all-round understanding of petrophysical properties. The goal of this essay is to understand the laboratory measurements and basic definitions of the petrophysical properties porosity, permeability, relative permeability, capillarity, and saturation. Pore-size distribution is presented as the common link between these properties.
Productivity is a measure of how efficiently goods and services are produced. Labour Productivity Growth is an economic indicator of a country's prosperity. Over the long-term productivity is the single most important determinant of a country's per capita income. Countries with high productivity are those that are innovative and able to adapt to the constant fluctuations of global economy. Such countries have a higher standard of living.
ADCOP – Abu Dhabi Crude Oil Pipeline Project." IPIC. N.p., 2014. Web. 13 May 2014.
This form of Henry’s Law can be used up to a pressure of about 200 kPa and liquid concentrations of 1 mol% (Carroll, 1991). This shows that at low partial pressures a plot of mole fraction of a compound vs. partial pressure of the compound in the g...
In industry, the performance specifications for a particular pump may be known, but the tests are usually based on water as the pumping medium. For liquids of significantly higher viscosity than water, these performance curves may only be accurate at certain flow rates, or they might not be valid at all, and it might be necessary to recalibrate the specifications for higher viscosity liquids.
Determinants of Productivity Determinants of Productivity Productivity is the quantity of output formed by one unit of production input in a unit of time. Inputs used in the production of the goods and services are the major determinants of any country’s productivity; they are also called factors of production. There are four major determinants of productivity in any country’s economy. Land: the land itself, and raw materials such as oil and minerals beneath it. The natural resources that are available without alteration or effort on the part of humans.
Production Functions A production function in general, without specifying what kind, is related to the output of a production process which starts with the factors of production. Production functions are an integral part of explaining marginal products as well as allocative efficiency. There are different classifications for production functions, and what constitutes them, determined by the type of production. This article of the WIKI aims to focus on the Substitional production function, explaining what it is and means, as well as the limitations, of doing the same.
Third, the liquid will enter to the expansion valve with the higher pressure and leaves with the low pressure.
The typical work activities and what you might expect as a petroleum engineer would be liaising with geoscientists, production and reservoir engineers, and other such people to predict production potential. They also compile development plans using mathematical models and select accurate tubing size and suitable equipment for their plans and move onto designing "completions", which are the part of the well that communicates with the reservoir rock and fluids. Next, they design systems that will help the flow. For example, I can across some information that stated they use submersible pumps to help the flow. Of course, it is always important to keep a close eye on the fluid's behavior and its production and managing how a set of different wells might interact with one another.
Out of three phases of matter liquids and gas are considered to be fluids and we will talk about their application and uses in the modern world. In some cases, plasma is considered as the third type of fluid. Plasma as can be found in the universe as the most abundant form and its application is also very wide. According to the definition of Physics, fluids are defined as the substance, which deforms continuously under the application of applied stress. If the surface effects are not considered, then the flow of liquids and gases are considered same.
Labour is an active factor of production whereas land is a passive factor of production.