What do you think Petroleum Gas is?

[SherpaMcDerpa]

I know some of you may not care about this, but it's something that I've always been curious about and I'd like to get people's input on the following: What do you think Petroleum Gas is technically supposed to be?

I know it's a game, and I love it, but what is Petroleum Gas? I get that the point of this is to abstract real life ideas, but if we wanted to model this in a game, what is it?

I saw this thread and it died off with a couple of different opinions: viewtopic.php?f=27&t=80743

The current flow for acquiring is:

• 1. Pumpjack is placed on Crude Oil spot
  2. Pipes connect pumpjack crude oil output to Oil Refinery Input
  3. Oil Refinery processes Crude Oil and creates Petroleum Gas, Light Oil, and Heavy Oil

Based on how Natural Gas is processed, how Associated Petroleum Gas in oil reservoirs is processed, and the distillation process of Crude Oil, I see three possibilities:

• 1. Butane or Propane - Petroleum Gas is actually Butane or Propane through the distillation of Crude Oil. This is the most likely scenario because the real life process aligns most accurately to the current flow we see in Factorio: Crude Oil gets refined and creates multiple byproducts, including a gas.
  
  2. Associated Petroleum Gas or just "Associated Gas" - Petroleum Gas is Associated Gas (Methane, Butane, Propane, Ethane, etc) within an oil reservoir, and is piped through the same pipes connecting the Pumpjack to the Oil Refinery. Once processed by the Oil Refinery, the Associated Gas goes through the distillation process and its hydrocarbons are separated to form Natural Gas, Butane, Propane, etc. This is a possible scenario in Factorio and that the developers lumped all gases together and called them "Petroleum Gas" as the real-life name implies, but it then means that a single pipeline carries both oil and gas, and that an Oil Refinery also refines Natural Gas. This is not as realistic.
  
  3. Ethylene - Petroleum Gas is Ethylene, which is the actual carbon chain image depicted in Factorio for Petroleum Gas. While this would make sense somewhat because of the image, this scenario is less likely because Ethylene requires cracking yet Petroleum Gas is a byproduct of the Oil Refinery and not the Chemical Plant.

What are your thoughts?

[Koub]

The icon looks like some kind of weird methane, in more planar that the one we know. But for me, no need to give it a real-world name. Petroleum gas is enough, and with that, I don't feel pushed out of immersion by inaccuracies

[foamy]

Whatever it is it's clearly contaminated with sulphur, given you can get sulphur from it directly. The other primary use is plastic, which doesn't narrow things down much; there are a lot of different kinds of plastics and the Factorio version has an additional carbon source in the form of coal.

(Quite frankly coal would make more sense for being processed into sulphur :v)

[Khagan]

I know some of you may not care about this, but it's something that I've always been curious about and I'd like to get people's input on the following: What do you think Petroleum Gas is technically supposed to be?

It's just a collective term for the lightest fractions of the crude petroleum oil. Probably primarily propane and butane, as you suggest in your possibility 1.

A back-to-front but equivalent answer: it's LPG that hasn't been liquified yet .

Your mention of the associated gas is interesting though; one could perhaps argue that until you have advanced oil processing, you are not actually extracting and processing the oil at all, only the natural gas.

Whatever it is it's clearly contaminated with sulphur, given you can get sulphur from it directly. [...]
(Quite frankly coal would make more sense for being processed into sulphur :v)

If the original crude oil is 'sweet', then extracting sulphur primarily from the gas is not totally unreasonable. If the crude were 'sour', then you would need to remove a bunch of sulphur before doing any other processing.

[steinio]

At the end it's biter shit and bones rotted million years in the ground.

[blazespinnaker]

Yeh, I'm sure there was some original ideas of being accurate and than game play balancing and trying to devise interesting emergent problems became the priority as they thought more about the user. Glad they did. It is supposed to be a game after all As a metaphor for production and supply chains though it's pretty solid I think.