Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Energy 201 > Chapter 3 > Flashcards

Chapter 3 Flashcards

1
Q

Important physical properties of crude oil

A

Fluid Gravity
oil density
crude oil viscosity
specific gravity of the solution gas
gas solubility
Bubble-point pressure
oil formation volume factor
total formation volume factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define Crude oil gravity/density

A

the mass of a unit volume of
the crude at a specified pressure and temperature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Equation for the specific gravity of a crude oil

A

the ratio of the
density of the oil to density of water
Yo = Po / Pw

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do the values of Yo = Po / Pw mean?

A

This is the equation for specific gravity of a crude oil.
Yo - specific gravity of the oil
Po - density of the crude oil, lb/ft^3
Pw = density of the water, lb/ft^3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does this formula measure?
°API = (141.5 / Yo) - 131.5

A

The crude oil gravity in API gravity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The API gravities of crude oil usually ranges from 47° API for the ________ crude oils to 10° API for the _________ crude oils.

A

lighter
heavier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define bubble point pressure

A

the highest pressure at which the first bubble of gas is
liberated from the oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the difference between a unsaturated and saturated oil reservoir

A

Undersaturated is when Preservoir > Pb
When all gases are dissolved in the oil at the reservoir condition

Saturated is when Preservoir <= Pb
When gases are evolved and formed a gas-cap above the oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define gas solubility

A

the number of standard cubic
feet of gas which will dissolve in
one stock-tank barrel of crude oil
at specific pressure and
temperature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The gas solubility is a function of the ….

A

pressure, temperature, API
gravity, and gas gravity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define oil formation volume factor

A

Oil formation volume factor describes that if
you produce one barrel of oil from a specific reservoir, how
much the final and gas free volume of oil you have after you
released all gases at the surface.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the following formula used for?
Bo = (Vo)p,t / (Vo)sc
and what do the variables mean?

A

Oil formation volume factor
Bo - oil formation volume factor, bbl/STB
(Vo)p,t - volume of oil under reservoir pressure p and temperature t, bbl
(Vo)sc - volume of oil measured under standard conditions, STB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does STB stand for and what does it represent?

A

Stock Tank Barrel
refers to the volume of oil stored at stock tanks at the surface conditions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Define Isothermal compressibility coefficient of crude oil

A

co
is
defined for pressures above the bubble-point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Isothermal compressibility coefficient of crude oil uses these varaibles, what do the represent?
Co, Po, Bo

A

Co - isothermal compressibility, psi^-1
Po - oil density, lb/ft^3
Bo - oil formation volume factor, bbl/STB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Oil formation volume factor for undersaturated oil:
With __________ pressures above the bubble-point pressure, the oil formation volume factor decreases due to the ____________ of the oil

A

increasing
compression

17
Q

These variables are used in the oil formation volume factor for undersatured oils. Wat do they represent?
Bo, Bob, Co, P, Pb
Bo = Bob exp (-Co(P - Po))

A

Bo - oil formation volume factor at the pressure of interest, bbl/STB
Bob - oil formation volume factor at the bubble-point pressure, bbl/STB
P - pressure of interest, psia
Pb - bubble point pressure, psia

18
Q

Crude oil density is defined as

A

the mass of a unit volume of crude at a specific
pressure and temperature.

19
Q

Crude oil density has two equations to use. Why would I use one or the other?

A

One equation is above bubble point pressure and one is below or equal to bubble point pressure.

20
Q

These are the two equations for crude oil density. When do I use each one.
Po = (62.4Yo + 0.0136RsYg) / Bo

Po = Pob exp(Co(P - Pb))

A

Below or equal to bubble point pressure
Po = (62.4Yo + 0.0136RsYg) / Bo
Above bubble point pressure
Po = Pob exp(Co(P - Pb))

21
Q

Define viscosity

A

Viscosity is the internal resistance of the fluid to flow. This is an important
parameter which affects the flow of oil in the porous media and pipes.

22
Q

Viscosity of crude oil can be classified into 3 categories, what are they?

A

Dead-oil viscosity
saturated-oil viscosity
Undersaturated-oil viscosity

23
Q

Define dead -oil viscosity

A

The dead-oil viscosity is defined as the viscosity of
crude oil at atmospheric pressure (no gas in solution) and system
temperature.

24
Q

Define Saturated-oil viscosity

A

The saturated (bubble-point)-oil viscosity is
defined as the viscosity of the crude oil at the bubble-point pressure and
reservoir temperature.

25
Q

Define undersaturated-oil viscosity

A

The undersaturated-oil viscosity is
defined as the viscosity of the crude oil at a pressure above the bubble-point and reservoir temperature

26
Q

Important physical properties of natural gas

A

Apparent molecular weight, Ma
✓ Specific gravity, γg
✓ Compressibility factor, z
✓ Density, ρg
✓ Specific volume, v
✓ Isothermal gas compressibility coefficient, cg
✓ Gas formation volume factor, Bg
✓ Viscosity, µg

27
Q

Define apparent molecular weight formula

A

Ma = Σi=1(YiMi)
Ma - apparent molecular weight of a gas mixture
Mi - molecular weight of the ith component in the mixture
Yi - mole fraction of component i in the mixture

28
Q

Define standard volume

A

The standard volume is defined as the volume of gas
occupied by 1 lb-mol of gas at standard conditions.
Vsc = 379.4 scf/lb-mol

29
Q

Equation for gas density is

A

Pg = pMa / RT
Pg - density of the gas mixture, lb/ft^3
Ma - apparent molecular weight

30
Q

Define gas specific gravity/ how to calculate it

A

The specific gravity of a natural gas is defined as the ratio of the
density of the gas to density of air
Yg = Pg/Pair
Yg = Ma/Mair = Ma/28.96

31
Q

What do the variables in this formula mean?
Yg = Pg/Pair

A

Yg - gas specific gravity
Pair - density of the air
Pg - density of the gas

32
Q

What is the gas formation volume factor

A

The gas formation volume factor, Bg
, is defined as the ratio of
the volume of gas at the reservoir temperature and pressure to
the volume of oil at standard conditions

33
Q

What is this formula used for? define each variable
Bg = Vp,t / Vsc

A

Bg - gas formation volume factor, ft^3/scf
Vp,t - volume of gas at pressure p and temperature, t, ft^3
Vsc - volume of gas at standard conditions, scf

34
Q

Standard condition for pressure and temperature

A

14.7 psia
60° F

35
Q
A

Energy 201 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions