Why is the total volume of petroleum products made from crude oil > the volume of crude oil you started with?

> = "greater than"
"you" = "the refiner or refinery"

Short way to ask the same Q: Why is there a volumetric gain when processing crude oils through a refinery?

TWH 08182006
Total mass out in products< Total mass in as crude oil
Total volume out of products> Total volume in as crude oil
note:mass is less because part of the incoming crude ends up being used in the processing ie LNG and heavy fuel oil to power the refinery boilers heaters and thermal cracking units. TWH 08242006

5 Responses to “Why is the total volume of petroleum products made from crude oil > the volume of crude oil you started with?”

  1. Kirk M Says:

    When you crack heavy molecules you increase the total number of molecules. These have varying densities and ability to work as solvents/solutes. Thus they occupy more space. Note the volume changes but you will lose weight as there isnt a market for some of the lighter fractions. They flare those off. Ever notice the tall pipe with a fire on top?

  2. tydlywnks Says:

    It’s probably due to the things they add to the crude oil as it goes through the refinining process.

  3. Epicarus Says:

    I’m assuming noting is added, mass remains constant?

    When you physically and/or chemically alter matter, a consequence is that you’ll form different compounds in different states. The chances that these new compounds and/or different states will have the overall same density is pretty low.
    Example: When you freeze water, Volume increases.
    When water is electrolyzed, Volume increases.
    Etc…

  4. steveSang Says:

    Because of the miscability, ability of substances to disolve in each other.

  5. thewordofgodisjesus Says:

    I dunno. I don’t drink the stuff.