List of abbreviations in oil and gas exploration and production
Gas Oil Ratio is the volume of gas that is produced from crude oil when the oil is being extracted from the reservoir to the earth's surface through production tubing. This is generally related to associated gas (AG) or saturated gas in the oil reservoir. It is represented as standard cubic feet per stock tank barrel (scf/stb). It is also known as Gas to Oil Ratio and abbreviated as GOR. Apr 01, · The solution gas-oil ratio (GOR) is a general term for the amount of gas dissolved in the oil. Heavy oils (lower API gravity) has lower capacity to contain dissolved gas than lighter oils. Solution GOR in black oil systems typically range from 0 to approximately scf / bbl.
Gas Oil Ratio is the volume of gas that is produced from crude oil when the oil is being extracted from the reservoir to the earth's surface through production tubing. This is generally related to associated gas AG or saturated gas in the oil reservoir. When crude oil is produced from an oil well, natural gas known as associated gas may also be extracted along with the oil.
A ratio gas to oil ratio is calculated which lets the analysts know how much gas is produced how to calculate r in statistics with the oil. More specifically, gas to oil ratio is the amount of gas produced from hydrocarbon solution to the volume of oil at standard conditions. Toggle navigation Menu. Petropedia explains Gas Oil Ratio GOR When crude oil is produced from an oil well, natural gas known as associated gas may also be extracted along with the oil.
The associated gas is natural gas that is dissolved in the oil and is produced along with inn crude oil. Heavy crude oil has low API gravity and low what is gor in oil and gas of dissolved gas as compared to lighter crude oil.
Share this:. Related Whqt. Related Articles. The Bunkering of Marine Oil Tankers. Related Tags. Misspellings: Gasoil Ratio. Connect with us. Please Wait Latest Articles. MORE Newsletters.
GVF; GOR & GLR units?
Mar 21, · GOR is the ratio of volumetric flow of produced gas to the volumetric flow of crude oil for crude oil and gas mixture sample. For any hydrocarbon mixture produced from an oil production well, the proportion of liquid and vapor phases in the mixture changes with changing temperature and pressure conditions. The produced gas-oil ratio (GOR) at any particular time is the ratio of the standard cubic feet of total gas being produced at any time to the stock-tank barrels of oil being produced at that same instant. Hence, the name instantaneous gas-oil ratio. Equation in Chapter 6 describes the GOR mathematically by the following expression. Just like it's been mentioned in the question, GOR means gas-oil ratio. It is a measure of the volume of dissolved gas within the oil with respect to the oil volume. The GOR is measured in scf/STB which stands for standard cubic feet of gas released per stock tank barrel of oil.
Typically, there are five main types of reservoir fluids: black oil, volatile oil, condensate retrograde gas , wet gas, and dry gas. Each of these fluid types require different approaches when analyzing the reservoir, so it is important to identify the correct fluid type early on in the reservoir's life.
Laboratory analysis is our primary method for determining and quantifying fluid type, but production information such as initial production gas-oil ratio GOR , gravity of the stock-tank liquid, and the color of the stock-tank liquid are also useful indicators. Black oils are made up of a variety of components including large, heavy, and non-volatile hydrocarbons.
The phase diagram is shown below. If the pressure is at 2, the oil is at its bubble point, and is said to be saturated - meaning the oil contains the maximum amount of dissolved gas and can't hold any more gas. A reduction in pressure at this point will release gas to form a free gas phase inside the reservoir. Additional gas evolves from the oil as it moves from the reservoir to the surface. This causes some shrinkage of the oil. Black oil is often called low shrinkage crude oil or ordinary oil.
Black oils are dark in color indicating the presence of heavy hydrocarbons. Volatile oils contain fewer heavy molecules and more intermediate components ethane through hexane than black oils.
The color is generally lighter than black oil — brown, orange, or green. Gas associated with volatile oils tends to be very rich and similar to retrograde condensate gas. The phase envelope for a volatile oil tends to cover a much narrower temperature range when compared to a black oil; but like a black oil, the reservoir temperature is always lower than the critical temperature for the fluid.
As the reservoir temperature approaches the critical temperature a volatile oil will become more gas-like such that with even moderate depletion, a volatile oil reservoir can flash mainly to gas and have a relatively low liquid content.
However, the reservoir temperature of a condensate gas reservoir is greater than the critical temperature of the fluid, and so where a volatile oil is a liquid at original reservoir pressure and temperature, a condensate gas is a gas. As pressure is reduced in a condensate gas reservoir, the fluid will pass through the dew point and large volumes of liquid will condense in the reservoir. Since the gas flows preferentially to oil, much of this oil will be unrecoverable. Consequently, it is important to recognize that a reservoir contains a condensate gas and re-inject dry gas to maintain reservoir pressure above the dew point to maximize recovery of the liquids.
In the diagram below, the retrograde gas exists completely in a gaseous state inside the reservoir at point 1. As the pressure decreases, the condensate exhibits a dew point at point 2. As the reservoir further depletes and the pressure drops, liquid condenses from the gas to form a free liquid inside the reservoir. Natural gas that contains significant heavy hydrocarbons such as propane, butane and other liquid hydrocarbons is known as wet gas or rich gas. Wet gas exists solely as a gas in the reservoir throughout the reduction in reservoir pressure.
Unlike retrograde condensate, no liquid is formed inside the reservoir. However, separator conditions lie within the phase envelope, causing some liquid to be formed at the surface.
This surface liquid is normally called condensate, and the reservoir gas is sometimes called condensate-gas, which leads to a lot of confusion between wet gasses and retrograde condensate. The entire phase diagram of a wet gas will lie below the reservoir temperature. Note that the pressure path line does not enter the phase envelope, meaning no liquid is ever formed inside the reservoir.
Wet gases produce stock tank liquid with the same range of gravities as the liquids from retrograde gases. However, the gravity of the stock tank liquid does not change during the life of the reservoir. Natural gas that occurs in the absence of condensate or liquid hydrocarbons, or gas that had condensable hydrocarbons removed, is called dry gas. It is primarily methane with some intermediates. The hydrocarbon mixture is solely gas in the reservoir and there is no liquid condensate surface liquid formed either in the reservoir or at surface.
The pressure path line does not enter into the phase envelope in the phase diagram, thus there is only dry gas in the reservoir. Note, the surface separator conditions also fall outside the phase envelope in contrast to wet gas ; hence no liquid is formed at the surface separator.