Reservoir Fluid Properties

Question 1

Crude Oil

Answer 1

mixture of hydrocarbons in liquid form within natural underground reservoirs and remains in liquid form at atm temp and pressures. *Black Oil (black, brown, or amber in colour)

Question 2

Natural Gas

Answer 2

mixture of hydrocarbons and varying quantities of non-hydrocarbons that exist in natural reservoirs in the gaseous (or supercritical) form (or in solution crude oil)

Question 3

Condensate

Answer 3

a low-density, high-API gravity lequid with a low vapour pressure. Can occur in liquid or vapour phase, depending on temp and pressure within reservoir.

Question 4

Bitumen

Answer 4

A tar-like mixture of hydrocarbons with a density greater than 960 kg/m³.

Question 5

Alkanes

Answer 5

• open chains with single (saturated) C-C bonds

* commonly known as paraffins (Methane(CH4), Ethane(C2H6), Propane(C3H8), Butane(C4H10), Hexane(C6H14), Octane(C8H18))

Question 6

Alkenes

Answer 6

• Commonly known as olefins
• have double-bonded C structure (C=C)
• occurrence is rare in natural reservoir

Question 7

Alkynes

Answer 7

• have triple bond (unsaturated) structures (C≡C), produced in petrochemical complexes

Question 8

Aromatics

Answer 8

are also called arenes.
•The name aromaticsis because of the pleasant odour that many of them have. However, they are generally very toxic.
•Most common known aromatic compounds are: Benzene (C6H6), toluene (C7H8), and xylene (C8H10).

Question 9

Gas hydrates

Answer 9

ice-like substances composed of water and natural gas that form when gases, combine with water at low temperature and high pressure

Question 10

Waxes

Answer 10

solids deposited from the crude oil when cooled below a certain temperature. They are generally composed of heavy paraffins

Question 11

Natural Gas Composition

Answer 11

Typically natural gas contains 70 to 100% methane, CH4

Question 12

Dry Gas

Answer 12

less than 1.33L condensate per m3 (contains methane and ethane)

Question 13

Wet Gas

Answer 13

more than 4.00 L condensate per m3 (contains >50% propane and butane)

Question 14

Sweet Gas

Answer 14

contains NO hydrogen sulphide

Question 15

Sour Gas

Answer 15

contains more than trace amounts of highly toxic hydrogen sulphide

Question 16

what is API Gravity

Answer 16

dimensionless measure of density used in petroleum industry.

• Heavy Oil - 10 to 22.3
• Medium Oil - 22.3 to 31.1
• Light Oil - 31.1 +

Question 17

Conventional Oil

Answer 17

• is able to flow naturally or can be pumped to surface without being heated or diluted (light, medium, heavy oils)
• Sandstone and Carbonate Reservoirs
• • Do not require extensive treatment (Fracking)

Question 18

Unconventional Oil

Answer 18

• oil that does not flow, or cannot be pumped without being heated or diluted (bitumen and heavy oil that is thick/viscous)

Question 19

Normal Pressure within a reservoir have gradients that are within the range 9.8 to __ kPa/m

Answer 19

11.0 (brine)

Question 20

Abnormal Pressures

Answer 20

if pressures within reservoir fall outside of 9.8-11 kPa/m

Question 21

Overpressure

Answer 21

gradients > 11,0 kPa/m

Question 22

Underpressure

Answer 22

pressures < 9.8 kPa/m