Showing posts with label Oil and Gas. Show all posts
Showing posts with label Oil and Gas. Show all posts

Sunday, 9 September 2012

Crude Oil Refining

Crude Oil refining
A refinery is a factory. A refinery takes a raw material (crude oil) and transforms it into petrol and hundreds of other useful products. A typical large refinery costs billions of pounds to build and millions more to run and upgrade. It runs around the clock 365 days a year, employs  hundreds of people and occupies as much land as several hundred football pitches.
A REFINERY breaks crude oil down into its various components, which then are selectively changed into new products. This process takes place inside a maze of pipes and vessels. The refinery is operated from a highly automated control room.
All refineries perform three basic steps:
  • Separation (fractional distillation)
  • Conversion (cracking and rearranging the molecules)
  • Treatment

Oil Refinery Processing and Outputs

Oil Refinery Processing and Outputs
  • It is important to realise that the column is hot at the bottom and cool at the top.
  • The crude oil separates into fractions according to weight and boiling point.
  • The lightest fractions, including petrol and liquid petroleum gas (LPG), vapourise and rise to the top of the tower.
  • Kerosine (aviation fuel) and diesel oil, stay in the middle of the tower
  • Heavier liquids separate lower down.
  • The heaviest fractions with the highest boiling points settle at the very bottom.

The following table shows how the behaviour of the hydrocarbon molecules alter:
AT THE TOP OF THE COLUMN
AT THE BOTTOM OF THE COLUMN



  • Short carbon chains

  • Long carbon chains
  • Light molecules

  • Heavy molecules
  • Low boiling points

  • High boiling points
  • Gases & very runny liquids

  • Thick, viscous liquids
  • Very volatile

  • Low volatility
  • Highly flammable

  • Not very flammable
  • Light colour

  • Dark colour



Petrol comes off near the top of the column. Does the list above describe petrol?
Fuel oil comes off near the bottom of the column. Does the list above describe fuel oil?
The fractions are now ready for piping to the next areas within the refinery. Some fractions require very little additional processing. However, most molecules require much more processing to become high-value products.

Conversion: cracking and rearranging molecules

Some fractions from the distillation towers need to be transformed into new components . This is where a refinery makes money, because the low-value fractions that aren't in great demand can be converted to petrol and other useful chemicals.
The most widely used conversion method is called cracking because it uses heat and pressure to "crack" heavy hydrocarbon molecules into lighter ones. A cracking unit consists of one or more tall, thick-walled, reactors and a network of furnaces, heat exchangers and other vessels. Catalytic cracking, or "cat cracking," is the basic petrol-making process. Using intense heat (about 600°C), low pressure and a powdered catalyst (a substance that speeds up a  chemical reaction), the cat cracker can convert most of the heavy fractions into smaller more useful molecules.
Some refineries also have cokers, which use heat and moderate pressure to turn the really heavy fractions into lighter products and a hard, coal like substance that is used as an industrial fuel.
Cracking and coking are not the only forms of conversion. Other refinery processes, instead of splitting molecules, rearrange them to add value. Alkylation makes petrol components by combining some of the gaseous byproducts of cracking. The process, which essentially is cracking in reverse, takes place in a series of large, horizontal vessels.
Reforming uses heat, moderate pressure and catalysts to turn naphtha into high-octane petrol.

Treatment: the finishing touch

Today, a major portion of refining involves blending, purifying, fine-tuning and improving products to meet specific requirements. To make  petrol, refinery workers carefully blend together a variety of hydrocarbons. Technicians also add performance additives and dyes that distinguish the various grades of fuel. By the time the petrol is pumped into a car it contains more than 200 hydrocarbons and additives.
Example: Petrol companies produce different blends of fuels to suit the weather. In winter, they put in more volatile hydrocarbons (with short carbon chains) and in summer they add less volatile hydrocarbons to compensate for the higher temperatures.

- Source (http://www.moorlandschool.co.uk/earth/oilrefinery.htm)

Oil Refinery

Oil Refinery

refinery picture A refinery is a factory. A refinery takes a raw material (crude oil) and transforms it into petrol and hundreds of other useful products. A typical large refinery costs billions of pounds to build and millions more to run and upgrade. It runs around the clock 365 days a year, employs  hundreds of people and occupies as much land as several hundred football pitches.
A REFINERY breaks crude oil down into its various components, which then are selectively changed into new products. This process takes place inside a maze of pipes and vessels. The refinery is operated from a highly automated control room.
All refineries perform three basic steps:
  • Separation (fractional distillation)
  • Conversion (cracking and rearranging the molecules)
  • Treatment

Modern separation involves piping crude oil through hot furnaces. The resulting liquids and vapours are passed into distillation towers:-


FRACTION B Pt  oC Number of carbons Uses









small segment of refinery6.gif (1125 bytes) »Refinery gas
1-4 Bottled gas, fuels

»Petrol 40 ~8 Fuel for cars

small segment of refinery5.gif (443 bytes) »Naptha 110 ~10 Raw material for chemicals and plastics.

small segment of refinery4.gif (440 bytes) »Kerosine 180 ~15 Fuel for Aeroplanes

small segment of refinery3.gif (1010 bytes) »Diesel 250 ~20 Fuel for cars and lorries

small segment of refinery2.gif (525 bytes) »Oils 340 ~35 Fuel for Power Stations, Lubricants and grease
Hot crude » small segment of refinery1.gif (489 bytes) »Bitumen 400+ 40+ Road surfacing.
















  • It is important to realise that the column is hot at the bottom and cool at the top.
  • The crude oil separates into fractions according to weight and boiling point.
  • The lightest fractions, including petrol and liquid petroleum gas (LPG), vapourise and rise to the top of the tower.
  • Kerosine (aviation fuel) and diesel oil, stay in the middle of the tower
  • Heavier liquids separate lower down.
  • The heaviest fractions with the highest boiling points settle at the very bottom.

The following table shows how the behaviour of the hydrocarbon molecules alter:
AT THE TOP OF THE COLUMN
AT THE BOTTOM OF THE COLUMN



  • Short carbon chains

  • Long carbon chains
  • Light molecules

  • Heavy molecules
  • Low boiling points

  • High boiling points
  • Gases & very runny liquids

  • Thick, viscous liquids
  • Very volatile

  • Low volatility
  • Highly flammable

  • Not very flammable
  • Light colour

  • Dark colour



Petrol comes off near the top of the column. Does the list above describe petrol?
Fuel oil comes off near the bottom of the column. Does the list above describe fuel oil?
The fractions are now ready for piping to the next areas within the refinery. Some fractions require very little additional processing. However, most molecules require much more processing to become high-value products.

Conversion: cracking and rearranging molecules

Some fractions from the distillation towers need to be transformed into new components . This is where a refinery makes money, because the low-value fractions that aren't in great demand can be converted to petrol and other useful chemicals.
The most widely used conversion method is called cracking because it uses heat and pressure to "crack" heavy hydrocarbon molecules into lighter ones. A cracking unit consists of one or more tall, thick-walled, reactors and a network of furnaces, heat exchangers and other vessels. Catalytic cracking, or "cat cracking," is the basic petrol-making process. Using intense heat (about 600°C), low pressure and a powdered catalyst (a substance that speeds up a  chemical reaction), the cat cracker can convert most of the heavy fractions into smaller more useful molecules.
Some refineries also have cokers, which use heat and moderate pressure to turn the really heavy fractions into lighter products and a hard, coal like substance that is used as an industrial fuel.
Cracking and coking are not the only forms of conversion. Other refinery processes, instead of splitting molecules, rearrange them to add value. Alkylation makes petrol components by combining some of the gaseous byproducts of cracking. The process, which essentially is cracking in reverse, takes place in a series of large, horizontal vessels.
Reforming uses heat, moderate pressure and catalysts to turn naphtha into high-octane petrol.

Treatment: the finishing touch

Today, a major portion of refining involves blending, purifying, fine-tuning and improving products to meet specific requirements. To make  petrol, refinery workers carefully blend together a variety of hydrocarbons. Technicians also add performance additives and dyes that distinguish the various grades of fuel. By the time the petrol is pumped into a car it contains more than 200 hydrocarbons and additives.
Example: Petrol companies produce different blends of fuels to suit the weather. In winter, they put in more volatile hydrocarbons (with short carbon chains) and in summer they add less volatile hydrocarbons to compensate for the higher temperatures.
Back to OIL & GA


Oil Refinery

Oil Refinery

Oil Storage Container

Oil Storage Container

Oil Storage Container



Upstream - Midstream - Downstream

Upstream,Midstream,Downstream

The upstream sector

The upstream sector involves the exploration for and extraction of petroleum crude oil and natural gas. The upstream oil sector is also known as the exploration and production (E&P) sector.
The upstream sector includes the searching for potential underground or underwater oil and gas fields, drilling of exploratory wells, and subsequently operating the wells that recover and bring the petroleum crude oil and/or raw natural gas to the surface.

The midstream sector

The midstream involves storing, marketing and transporting petroleum crude oil, natural gas, natural gas liquids (mainly ethane, propane and butane) and byproduct sulfur. Midstream operations are sometimes included in the downstream category.

The downstream sector

The downstream sector involves the refining of petroleum crude oil and the processing of raw natural gas. It includes the selling and distribution of processed natural gas and the products derived from petroleum crude oil such as liquified petroleum gas (LPG), gasoline (or petrol), jet fuel, diesel oil, other fuel oils, petroleum asphalt and petroleum coke.
The downstream sector includes petroleum refineries,[1] petroleum product distribution, retail outlets and natural gas distribution companies.

Byproduct sulfur

Petroleum crude oil is a mixture of hundreds of hydrocarbons, many of which contain sulfur that is removed during the refining of the crude oil. Raw natural gas also has sulfur-containing compounds, which are removed in processing of the raw natural gas before it is distributed to consumers. The sulfur-containing compounds removed in the refining and processing of petroleum crude oil and raw natural gas are subsequently converted into byproduct elemental sulfur. The production and marketing of the byproduct sulfur is considered to be part of the downstream sector.
The vast majority of the 64,000,000 metric tons of sulfur produced worldwide in 2005 was byproduct sulphur from refineries and natural gas processing plants.[2]

Petrochemical industry

The petrochemical industry is not generally considered to be a part of the petroleum industry. However, it is sometimes listed as a part of the downstream sector and sometimes as a fourth sector of the petroleum industry.

- Source (http://en.citizendium.org/wiki/upstream,_midstream_and_downstream_%28petroleum_industry%29)

Oil Recovery

Oil Recovery

Oil Refinery Plant

Oil Refinery Plant

Enhanced Oil Recovery

Enhanced Oil Recovery

Drilling Rig - Oil Well

Drilling Rig Oil Well

Petroleum Refining Process

Petroleum Refining Process

Oil Well

Oil Well

An oil well is a general term for any boring through the Earth's surface that is designed to find and acquire petroleum oil hydrocarbons. Usually some natural gas is produced along with the oil. A well that is designed to produce mainly or only gas may be termed a gas well (Source :Wikipedia)