Oil & Gas

Question 1

How many litres in a barrell of oil

Answer 1

159

Question 2

What are the marketable products from an oil well?

Answer 2

Oil, natural gas or condensates

Question 3

How much Kerogen in source rock sufficient for commercial exploitation of crude oil and natural gas?

Answer 3

Kerogen concentrations as low as 1%–3% are generally sufficient to be make source rock (typically shales and limestones) suitable for commercial exploitation of crude oil and natural gas.

Question 4

What does the term “oil window” refer to?

Answer 4

describe the range of temperature or depth within which most of oil’s complex constituents are produced (fig. 1–1).This window is typically 80–220°C (176–428°F) or 2,200– 5,500 meters (7,200–18,000 feet).

Question 5

What are the drivers for the conversion of kerogen in source rock to oil and gas?

Answer 5

The key factor is temparature. Other factors include pressure, and the presence of hydrogen and water. As these various drivers exert their influence, the kerogen in source rock undergoes conversion to petroleum in a process called “maturation”

Question 6

What is meant by ‘maturation’?

Answer 6

The conversion of kerogen in source rock to oil/gas

Question 7

What is meant by ‘migration’?

Answer 7

when oil and gas move from source rock into a reservoir. virtually all commercially viable oil reservoirs result from migration that takes the hydrocarbons away from the source rock and into reservoir rock.

Question 8

What are hydrocarbon traps?

Answer 8

structural, stratigraphic, and combination traps prevent the movement of hydrocarbons from source rock into reservoirs.

Question 9

What is crude oil often found along with?

Answer 9

Crude oil is often found along with natural gas and saline (salty) water.

Question 10

What are the three parameters used to classify crude oil?

Answer 10

Geographic location in which it is produced (which affects the cost of transporting the crude to a refinery).
• API gravity (an oil industry measure of density;API is the American Petroleum Institute). Light crude oil has relatively low density; heavy crude has high density. Oil with an
API gravity (expressed as oAPI) below 10.0 is classified
as extraheavy.
• Sulfur content. Crude is generally called sweet if it contains relatively little sulfur or sour if it contains substantial amounts.

Question 11

What is the difference between a sweet and sour oil?

Answer 11

Sulfur content. Sweet oils contain relatively little sulfur and sour oils contain substantial amounts

Question 12

Why does sweet command a higher premium than sour?

Answer 12

because it has fewer environmental problems and requires less refining to meet sulfur-content standards imposed by buyers

Question 13

Each crude oil has unique molecular characteristics that are evaluated by a process called __________?

Answer 13

assay analysis

Question 14

What is West Texas Intermediate?

Answer 14

a very high quality sweet, light oil delivered at Cushing, Oklahoma, for North American oil. Cushing is the delivery point for WTI traded on the New York Mercantile Exchange (NYMEX), the most widely traded oil futures contracts in the world.

Question 15

What is Brent Blend?

Answer 15

made up of 15 oils from fields in the Brent and Ninian systems in the East Shetland Basin of the North Sea. Oil production from Europe and Africa, as well as Middle Eastern oil flowing to the West, tends to be priced using this benchmark.

Question 16

What is Dubai-Oman?

Answer 16

Dubai-Oman, used as benchmark for Middle East sour crude flowing to the Asia-Pacific region.

Question 17

What is the OPEC reference basket?

Answer 17

a weighted average of oils and blends from the 12 nations that make up the Organization of the Petroleum Exporting Countries.

Question 18

What are the unconventional types of crude oil?

Answer 18

Tar Sands and Shale Oil?

Question 19

What are tar sands?

Answer 19

A kind of heavy crude oil. Tar sands contain bitumen. he sticky, black, tarlike material is so thick that it must be heated or chemically diluted before it will flow

Question 20

Which countries have the highest sources of Tar sands?

Answer 20

Canada and Venezuela contain an estimated 3.6 trillion barrels (570 billion cubic meters) of bitumen and extraheavy oil.This represents about twice the volume of the world’s reserves of conventional oil.

Question 21

What is shale oil.

Answer 21

Trapped kerogen in relatively hard rocks called marks (composed primarily of clay and calcium carbonate). The trapped kerogen can be converted into crude oil using heat and pressure to simulate natural processes.

Question 22

Where are oil shales found?

Answer 22

Many countries but the USA has the largest deposits.

Question 23

What are the 3 types of wells where gas comes from?

Answer 23

oil wells, gas wells, and condensate wells.

Question 24

What is Natural gas that comes from oil wells is typically termed?

Answer 24

“associated gas.

Question 25

Natural gas from gas and

condensate wells in which there is little or no crude oil, is termed what?

Answer 25

Non Associated Gas

Question 26

What do condensate wells produce?

Answer 26

free natural gas along with a semi-liquid hydrocarbon condensate

Question 27

What other hydrocarbons is often found in natural gas?

Answer 27

it commonly exists in mixtures with other hydrocarbons, principally ethane, propane, butane, and pentanes (“Associated Hydrocarbons”)

Question 28

What other compunds are found with natural gas?

Answer 28

water vapor, hydrogen sulfide (H2S), carbon dioxide, helium,

nitrogen, and other compounds

Question 29

What are typical byproducts of natural gas processing?

Answer 29

ethane, propane, butane, …known as Natural Gas liquids

Question 30

What does the midstream part of the value chain typically include?

Answer 30

gas plants, LNG production and regasification, and oil and gas pipeline transport systems

Question 31

What are Subsea production systems?

Answer 31

wells located on the sea floor as opposed to the surface. the petroleum is extracted
at the seabed, and is then “tied-back” to a pre-existing production platform or
even an onshore facility, limited by horizontal distance or “offset”/

Question 32

When are subsea systems use? Do these systems hav the ability to drill?

Answer 32

Subsea systems are typically used at depths of 500
meters or more and do not have the ability to drill, only to extract and transport. Drilling and
completion is performed from a surface rig

Question 33

What are manifolds and gathering systems?

Answer 33

The
purpose of these pipelines is to allow setup of
production “well sets” so that for a given production
level, the best reservoir utilization well flow
composition (gas, oil, water), etc., can be
selected from the available wells.

Question 34

How are gas, water and oil separated?

Answer 34

Classic form is a gravity seperator. In gravity separation, the well flow is fed into a horizontal vessel. The
retention period is typically five minutes, allowing gas to bubble out, water to settle at the bottom and oil to be taken out in the middle

Question 35

What is gas processing?

Answer 35

Gas processing consists of separating the various
hydrocarbons and fluids from the pure natural gas to
produce what is known as “pipeline quality” dry natural
gas.

Question 36

What are Natural Gas Liquids and what are they used for?

Answer 36

Associated hydrocarbons, known as “natural gas liquids” (NGL) are ethane, propane and butane and are used as
raw materials for oil refineries or petrochemical plants and as sources of energy.

Question 37

Why is gas compression required?

Answer 37

Gas from a pure natural gas wellhead might have
sufficient pressure to feed directly into a pipeline
transport system. Gas from separators has generally lost so much pressure that it must be recompressed to
be transported

Question 38

how are gas pipelines inspected for corrosion and defects?

Answer 38

With Pigs. Pigs are intelligent
robotic devices that are propelled down pipelines to evaluate the interior of the pipe. Pigs can test pipe thickness, roundness, check for signs of
corrosion, detect minute leaks, and any other defect along the interior of the pipeline that may either restrict the flow of gas, or pose a potential safety risk

Question 39

Why is liquification of gas carried out?

Answer 39

the only practical solution to long distance
gas transportation whena pipeline is not available
or economical is to produce LNG at -162 °C. at the receiving end, a regasification terminal heats the
LNG to vaporization for pipeline distribution

Question 40

What is one of the important features of a successful refiner?

Answer 40

The economic success of a
modern refinery depends on its ability to accept
almost any available crude.