Nearly 25% of oil supply is non-combustible...

[Pepperman]

...and used by the lubricants and petrochemical sectors.

Anyone got a source for this little unreferenced factoid that I saw on Twitter this morning? What are we talking here? NGLs I assume? Anything else?

[Mark]

As I understand, in very broad terms and with current technology, we've got oil for approx. 20 years and gas for approx. 100 years...
As a result, big petrochemical companies are progressively moving their feedstocks from oil to gas to produce a whole range of chemicals...
These products are called GTL (Gas to Liquid)

http://www.chemicals-technology.com/projects/gtl/
http://www.shell.com/energy-and-innovat ... quids.html

[vtsnowedin]

...and used by the lubricants and petrochemical sectors.

Anyone got a source for this little unreferenced factoid that I saw on Twitter this morning? What are we talking here? NGLs I assume? Anything else?

Asphalt cement for road pavements. The bottom of every barrel after you refine off the gasoline and diesel etc. The amount varies with each crude source and I have no figure for the world total. Venezuela and Tobago have deposits of just asphalt that are " enormous."
(I was going to say "Huge" but Trump has poisoned that word forever. )

[fuzzy]

They can break tar into lighter oils if they want to. It just costs money and gas for heat, so it's not economic while there is runny oil. When it's £200/bbl then they will split tar.

[vtsnowedin]

They can break tar into lighter oils if they want to. It just costs money and gas for heat, so it's not economic while there is runny oil. When it's £200/bbl then they will split tar.

True but there are limits.

Asphalt Composition

Conventional chemical analysis shows that bitumens contain mainly carbon and hydrogen with small amounts of oxygen, nitrogen and sulphur and trace amounts of metals. A typical analysis is 83% carbon, 10% hydrogen, 7% oxygen, nitrogen and sulphur and trace amounts of vanadium, nickel, aluminium and silicon.

More complex methods of analysis, for example, infrared, ultraviolet and nuclear magnetic resonance, identify classical chemical groupings and confirm that bitumens are complex mixtures, mainly of high molecular weight hydrocarbons.
Using a selective solvent such as normal heptane, bitumen may be separated into asphaltenes (which are precipitated) and an oily fraction (maltenes). With adsorption chromatography the maltene fraction may be separated further into resins, aromatic oils and saturated oils. These four groups of constituents differ in nature:

- Asphaltenes
Are brittle brown to black amorphous solids. They contain mainly carbon and hydrogen but also oxygen, nitrogen and sulphur. Chemically, they consist of highly condensed aromatic compounds of high molecular weight. The concentration of asphaltenes varies with a higher proportion in the harder bitumens.

- Resins
Are brown to black, adhesive, shiny solids or semi-solids. They contain mainly carbon and hydrogen but also small amounts of oxygen, nitrogen and sulphur. Chemically they stand between the asphaltenes and the aromatics.

- Aromatic Oils
Are viscous dark brown liquids comprising mainly carbon, hydrogen and sulphur with minor amounts of oxygen and nitrogen. They contain numerous naphthenic-aromatic ring compounds.

- Saturated Oils
Are viscous liquids or solids which range from straw to white colour. They consist mainly of long chain saturated hydrocarbons with some branched chain compounds, alkyl aromatics with long side chains, and cyclic paraffins (naphthenes).

Average molecular weights cover a continuous range from saturated and aromatic oils (500 to 10001 through resins (1000 to 2000) to asphaltenes (greater than 2000).

Bitumens have a colloidal nature in which large structures (the asphaltenes) are dispersed in the form of micelles in an oily liquid phase (the maltenesl. Depending on the relative proportions of the four groups described above the structure will vary between "so/" in which the micelles are dispersed and a "gel" in which micelles are organized to more network-type structures. Thus, saturated oils which have little solvency power for asphaltenes, promote a predominantly gel character; aromatic oils have greater solvency power and promote a predominantly sol structure.

Composition, structure and behaviour are related. For example, air blowing changes aromatic oils to resins and resins to asphaltenes. Heavily blown bitumens have a predominantly gel character which has reduced temperature susceptibility. Deeper distillation will preferentially reduce the saturated oil content and give a bitumen which is more sol in character and has greater temperature susceptibility. Thus, an understanding of composition and structure assists in interpreting the rheological behaviour of bitumen and the effects of changes in temperature.

http://www.e-asphalt.com/ingles/composition.htm

[Pepperman]

Cheers for the comments. I've found some data for the US on the EIA website:

http://www.eia.gov/dnav/pet/pet_cons_ps ... mbbl_a.htm

Will post if I find any global data. Not sure the 25% stat is supported by that lot but will have a look in more detail at it.