Fractional Distillation

The various components of crude oil have different sizes, weights and boiling temperatures; so, the first step is to separate these components. Because they have different boiling temperatures, they can be separated easily by a process called fractional distillation. The steps of fractional distillation are as follows:

1. You heat the mixture of two or more substances (liquids) with different boiling points to a high temperature. Heating is usually done with high pressure steam to temperatures of about 1112 degrees Fahrenheit / 600 degrees Celsius.

2. The mixture boils, forming vapor (gases); most substances go into the vapor phase.3. The vapor enters the bottom of a long column (fractional distillation column) that is

filled with trays or plates. The trays have many holes or bubble caps (like a loosened cap on a soda bottle) in them to allow the vapor to pass through. They increase the contact time between the vapor and the liquids in the column and help to collect liquids that form at various heights in the column. There is a temperature difference across the column (hot at the bottom, cool at the top).

4. The vapor rises in the column.5. As the vapor rises through the trays in the column, it cools.6. When a substance in the vapor reaches a height where the temperature of the column

is equal to that substance's boiling point, it will condense to form a liquid. (The substance with the lowest boiling point will condense at the highest point in the column; substances with higher boiling points will condense lower in the column.).

7. The trays collect the various liquid fractions.8. The collected liquid fractions may pass to condensers, which cool them further, and

then go to storage tanks, or they may go to other areas for further chemical processing

The Product

1. Liquefied natural gas (LNG) is natural gas (predominantly methane, CH4) that has been converted to liquid form for ease of storage or transport. It takes up about 1/600th the volume of natural gas in the gaseous state. It is odorless, colorless, non-toxic and non-corrosive. Hazards include flammability after vaporization into a gaseous state, freezing andasphyxia. The liquefaction process involves removal of certain components, such as dust, acid gases, helium, water, and heavy hydrocarbons, which could cause difficulty downstream. The natural gas is then condensed into a liquid at close to atmospheric pressure by cooling it to approximately −162 °C (−260 °F); maximum transport pressure is set at around 25 kPa (4 psi).

2. Liquified petroleum gas or liquid petroleum gas (LPG or LP gas)

Also referred to as simply propane or butane, are flammable mixtures of hydrocarbon gases used as fuel in heating appliances, cooking equipment, and vehicles. It is increasingly used as an aerosol propellant and a refrigerant, replacing chlorofluorocarbons in an effort to reduce damage to the ozone layer. When specifically used as a vehicle fuel it is often referred to autogas. Varieties of LPG bought and sold include mixes that are primarily propane (C3H8), primarily butane (C4H10) and, most commonly, mixes including both propane

and butane. In the northern hemisphere winter, the mixes contain more propane, while in summer, they contain more butane. In the United States, primarily two grades of LPG are sold: commercial propane and HD-5. These specifications are published by the Gas Processors Association (GPA) and the American Society of Testing and Materials (ASTM). Propane/butane blends are also listed in these specifications.

3. Gasoline 

Also known as petrol (C9H20) outside of North America, is a transparent, petroleum-derived liquid that is used primarily as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives.

The characteristic of a particular gasoline blend to resist igniting too early (which causes knocking and reduces efficiency in reciprocating engines) is measured by its octane rating. Gasoline is produced in several grades of octane rating.Tetraethyllead and other lead compounds are no longer used in most areas to regulate and increase octane-rating, but many other additives are put into gasoline to improve its chemical stability, control corrosiveness and provide fuel system 'cleaning,' and determine performance characteristics under intended use. Sometimes, gasoline also contains ethanol as an alternative fuel, for economic or environmental reasons.

Gasoline, as used worldwide in the vast number of internal combustion engines used in transport and industry, has a significant impact on the environment, both in local effects (e.g., smog) and in global effects (e.g., effect on the climate). Gasoline may also enter the environment uncombusted, as liquid and as vapors, from leakage and handling during production, transport and delivery, from storage tanks, from spills, etc. As an example of efforts to control such leakage, many (underground) storage tanks are required to have extensive measures in place to detect and prevent such leaks. Gasoline contains benzene and other known carcinogens

4. Kerosene

Also known as lamp oil, is a combustible hydrocarbon liquid (C12H26-C15H32) widely used as a fuel in industry and households. Its name derives fromGreek: κηρός (keros) meaning wax, and was registered as a trademark by Abraham Gesner in 1854 before evolving into a genericized trademark. It is sometimes spelled kerosine in scientific and industrial usage. 

Kerosene is usually called paraffin in the UK, Southeast Asia, East Africa and South Africa. A more viscous paraffin oil is used as a laxative. A waxy solid extracted from petroleum is called paraffin wax.

Kerosene is widely used to power jet engines of aircraft (jet fuel) and some rocket engines, and is also commonly used as a cooking and lighting fuel and for fire toys such as poi. In parts of Asia, where the price of kerosene is subsidized, it fuels outboard motors on small fishing boats.Kerosene lamps are widely used for lighting in rural areas of Asia and Africa where electrical distribution is not available or too costly for widespread use. World total kerosene consumption for all purposes is equivalent to about 1.2 million barrels per day.

To prevent confusion between kerosene and the much more flammable gasoline, some jurisdictions regulate markings or colorings for containers used to store or dispense kerosene. For example, in the United States, the Commonwealth of Pennsylvania requires that portable containers used at retail service stations be colored blue, as opposed to red (for gasoline) or yellow (for diesel fuel).

Kerosene is a thin, clear liquid formed from hydrocarbons obtained from the fractional distillation of petroleum between 150 °C and 275 °C, resulting in a mixture with a density of 0.78–0.81 g/cm3 composed of carbon chains that typically contain between 6 and 16 carbon atoms per molecule.

5. Petroleum diesel

C15H32 – C16H34, also called petrodiesel or fossil diesel is the most common type of diesel fuel. It is produced from the fractional distillation of crude oil between 200 °C (392 °F) and 350 °C (662 °F) at atmospheric pressure, resulting in a mixture of carbon chains that typically contain between 8 and 21 carbon atoms per molecule. Diesel fuel  in general is any liquid fuel used in diesel engines, whose fuel ignition takes place, without spark, as a result of compression of the inlet air mixture and then injection of fuel. (Glow plugs, grid heaters and heater blocks help achieve high temperatures for combustion during engine startup in cold weather.) Diesel engines have found broad use as a result of higher thermodynamic and thus fuel efficiencies. This is particularly noted where diesel engines are run at part-load; as their air supply is not throttled as in a petrol engine, their efficiency still remains high.

The most common type of diesel fuel is a specific fractional distillate of petroleum fuel oil, but alternatives that are not derived from petroleum, such as biodiesel, biomass to liquid(BTL) or gas to liquid (GTL) diesel, are increasingly being developed and adopted. To distinguish these types, petroleum-derived diesel is increasingly called petrodiesel.

Sumber:

http://science.howstuffworks.com/environmental/energy/oil-refining4.htmhttps://en.wikipedia.org/wiki/Liquefied_natural_gashttps://en.wikipedia.org/wiki/Liquefied_petroleum_gashttps://en.wikipedia.org/wiki/Gasolinehttps://en.wikipedia.org/wiki/Kerosenehttps://en.wikipedia.org/wiki/Diesel_fuel