What is refinery cracking?

What is refinery cracking?

Cracking is a technique used in oil refineries whereby large and complex hydrocarbon molecules are broken down into smaller and lighter components that are more useful for commercial or consumer use. Cracking is a critical stage in the process of refining crude oil.

How is bitumen turned into oil?

Steam is injected into the oil sands deposit, reducing the viscosity of the bitumen. A mixture of mostly bitumen and water is pumped to the surface, where the water is recovered and recycled. The deposit is mined and trucked to a main processing plant. Hot water is added to the oil sands, producing a pumpable slurry.

What does cracking mean in the oil industry?

cracking, in petroleum refining, the process by which heavy hydrocarbon molecules are broken up into lighter molecules by means of heat and usually pressure and sometimes catalysts. Cracking is the most important process for the commercial production of gasoline and diesel fuel.

How is bitumen extracted?

Extraction involves the separation of bitumen from sand using water-based gravity separation. The bitumen attaches to free air bubbles and rises to the top of the vessel, forming an intermediate froth product. The heavy sand sinks to the bottom and is pumped out to the tailings plant.

How is cracking done?

Cracking is the name given to breaking up large hydrocarbon molecules into smaller and more useful bits. This is achieved by using high pressures and temperatures without a catalyst, or lower temperatures and pressures in the presence of a catalyst. The octane is one of the molecules found in petrol (gasoline).

What produces cracking?

Cracking is a reaction in which larger saturated hydrocarbon molecules are broken down into smaller, more useful hydrocarbon molecules, some of which are unsaturated: the products of cracking include alkanes and alkenes , members of a different homologous series.

Why is bitumen different to other oil products?

Because bitumen is denser and more tar-like in its consistency, it is extracted differently than conventional crude oil, which is directly pumped from the ground. An oil field expert explains how bitumen is “more like a solid, like tar, than conventional oil which makes it hard to pump.

How is bitumen extracted and converted to heavy oil?

Upgrading is a process by which bitumen is transformed into light/sweet synthetic crude oil (SCO) by fractionation and chemical treatment, removing virtually all traces of sulphur and heavy metals. About one-third of Alberta’s bitumen is upgraded into SCO before being sold to downstream refineries.

Why is cracking important in oil refinery?

Cracking is important for two main reasons: It helps to match the supply of fractions with the demand for them. The supply is how much of a fraction an oil refinery produces. Since cracking converts larger hydrocarbons into smaller hydrocarbons, the supply of fuels is improved.

Why is cracking of naphtha important in an oil refinery?

cracking of naphtha. It is important to ensure that the feedstock does not crack to form carbon, which is normally formed at this temperature. This is avoided by passing the gaseous feedstock very quickly and at very low pressure through the pipes which run through the furnace.

Is bitumen a oil?

The bitumen is a form of crude oil that can be separated out from the mixture. In its natural state, it is very dense and highly viscous. In order to transport the oil sands, the natural bitumen is processed or diluted.

How is bitumen made?

Bitumen, also known as asphalt in the United States, is a substance produced through the distillation of crude oil that is known for its waterproofing and adhesive properties. Bitumen production through distillation removes lighter crude oil components, such as gasoline and diesel, leaving the “heavier” bitumen behind.

Can a simple refinery process bitumen from the oil sands?

Simple refineries can only process light crude feedstock with a low sulphur content. Bitumen produced from the oil sands would be too heavy and too sour for a simple refinery. In order for bitumen to be sold to a simple refinery, it must first be upgraded into a lighter crude oil.

How do you crack bitumen?

Bitumen can either be cracked or diluted to reduce viscosity. In a cracking refinery, either a Coker is used to thermally crack heavy aromatics and paraffins into lighter molecules via carbon rejection or a hydrocracker can be used to add hydrogen and split molecules.

What is the difference between bitumen and crude oil?

In contrast, upgraded bitumen (synthetic crude oil) is light, sweet and virtually impurity-free. This greatly increases the marketability of the crude, making is saleable to almost any type of refinery.

What is bitumen (tar sands)?

Bitumen is commonly called ‘tar sands’ or ‘oil sands’. The world reserve of bitumen is about 5500 billion barrels of oil. 1 Assuming that the current world consumption of crude oil is about 35 billion barrels per year, 2 global reserves of bitumen potentially can supply the world with fuels for over 100 years.