How does solution gas drive help with oil recovery?
In a solution gas drive reservoir perforated down dip, gravity drainage can cause released solution gas to migrate upward and oil to flow downward, conserving reservoir energy and increasing recovery to near that of a water drive.
What is a solution gas drive reservoir?
Solution gas drives are found in saturated reservoirs, in which the ini-tial pore pressure is above the bubblepoint. As oil is produced, the reservoir pressure drops below the bubblepoint, gas bubbles come out of solution and expand in the oil. Solution gas can also be liberated from water.
Which is the most efficient recovery mechanism for a gas reservoir Why?
Waterdrive is the most efficient drive mechanism, followed by gasdrive and gravity drainage. Reservoir-drive mechanisms are also called natural drives.
What is reservoir drive mechanisms?
The reservoir drive mechanism supplies the energy that moves the hydrocarbon located in a reservoir container toward the wellbore as fluid is removed near the wellbore.
What are the three types of primary recovery for an oil reservoir?
There are three main types of EOR, including chemical flooding, gas injection and thermal recovery. Increasing the cost of development alongside the hydrocarbons brought to the surface, producers do not use EOR on all wells and reservoirs.
What is solution gas oil ratio?
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.
What is bubble point in oil and gas?
Bubble Point Curve—the curve that separates the pure liquid (oil) phase from the two-phase (natural gas and oil) region. This means that at a given temperature, when pressure decreases and below the bubble point curve, gas will be emitted from the liquid phase to the two-phase region.
What are the three types of driven mechanism *?
The primary drive mechanisms in oil reservoirs are as follows [1,2]: Liquid and rock expansion drive. Solution gas or depletion drive. Gas cap drive.
When a gas reservoir is underlain by oil the oil zone is called?
3. Gas-cap reservoir. If the initial reservoir pressure is below the bubblepoint pressure of the reservoir fluid, as indicated by point 3 on Figure 1-1, the reservoir is termed a gas-cap or two-phase reservoir, in which the gas or vapor phase is underlain by an oil phase.
What is gas injection in oil recovery?
Gas injection, which uses gases such as natural gas, nitrogen, or carbon dioxide (CO2) that expand in a reservoir to push additional oil to a production wellbore, or other gases that dissolve in the oil to lower its viscosity and improves its flow rate.
What methods would you use to enhance oil recovery from an existing reservoir?
Methods. There are three primary techniques of EOR: gas injection, thermal injection, and chemical injection. Gas injection, which uses gases such as natural gas, nitrogen, or carbon dioxide (CO2), accounts for nearly 60 percent of EOR production in the United States.
How do you calculate solution GOR?
Solution GOR at or above bubblepoint pressure can be obtained as the sum of the estimated stock-tank GOR and the measured separator GOR. The equation was derived with data from two-stage separations of 301 black-oil samples.
What is the difference between bubble point and dew point?
The main difference between bubble point and dew point is that bubble point is the temperature at which a liquid forms the first bubble of vapor, commencing the vaporization of that liquid whereas dew point is the temperature at which the first drop of dew forms from vapor, commencing the condensation of a liquid.
What is depletion drive?
A depletion drive reservoir is characterized by a rapidly increasing gas–oil ratio from all wells, regardless of their structural position. After the reservoir pressure has been reduced below the bubble point pressure, gas evolves from solution throughout the reservoir.
How many types of cam drives are there?
There are two types, the double overhead camshaft (DOHC) and single overhead camshaft (SOHC).
What is difference between gas lift and gas injection?
Although the terms are sometimes interchanged, gas injection and gas lift are two separate processes that are used to increase production. While gas injection is a secondary production method, gas lift is a type of artificial lift.
What is enhanced gas recovery?
Enhanced Recovery and Coal Gas Modeling The term enhanced gas recovery is often used to describe the recovery of difficult-to-recover natural gas. This includes natural gas contained in tight gas sands, shales, and coal seams. Many of these geological formations contain significant volumes of natural gas.
Solution gas drive reservoirs Oil reservoirs that do not initially contain free gas but develop free gas on pressure depletion are classified as solution gas drives. The solution gas drive mechanism applies once the pressure falls below the bubblepoint. Both black- and volatile-oil reservoirs are amenable to solution gas drive.
Does solution-gas drive improve recovery performance in heavy oil?
The experimental and simulation results indicate that gas mobility in solution-gas drive in heavy oil is much less than in light oil, leading to improved recovery performance of the former. Production from some of the heavy oil reservoirs in Canada and Venezuela has led to unexpectedly high oil rates and recoveries under solution-gas drive.
What is the GOR of a black oil reservoir?
The producing GOR remains constant and equal to the initial dissolved GOR of 838 scf/STB; no free gas evolves. Fig.1 – Pressure (p), gas saturation (Sg). producing GOR (R), and cumulative producing GOR (Rps) as a function of OOIP recovered for a solution gas drive, black oil reservoir.
Are black-and volatile-oil reservoirs amenable to solution gas drive?
Both black- and volatile-oil reservoirs are amenable to solution gas drive. Other producing mechanisms may, and often do, augment the solution gas drive. Solution gas drive reservoir performance is used as a benchmark to compare other producing mechanisms.