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How an oil refinery works

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Re: How an oil refinery works

#151

Post by pfdietz »

tgsovlerkhgsel wrote: post #146
jyounker wrote: post #135

Earlier quoted context omitted.

Wow. I grew up in Houston, and I assumed that the smell from these plants was pretty-much unavoidable. It's shocking (and I guess not all that surprising) that this is a choice that manufacturers make. I guess it really does depend on the economic power of the surrounding communities.

Likewise, a lot of the complaints people have about data centers are engineering choices. If companies can get away with it, they'll do it the cheap way.

What could be needed is internalization of external costs. If you release chemicals that cause problems, charge the polluter, and send the charges to those affected.

On a global scale this breaks down, because governments value the lives of non-citizens orders of magnitude below the lives of their own citizens. The US will spend millions to save one expected life at home; it will avoid spending thousands to save one expected life in a third world country.

Re: How an oil refinery works

#152

Post by newyankee »

diginova wrote: post #44

My father actually works at the Jamnagar refinery. I was bought up in there seeing and visiting the refinery as families are allowed for some trips every now and then. I learnt a lot of this process of refining out of curiosity of what my father did and it was just so cool. The refinery in context is the world's largest since more than a decade and seeing it with your own eyes, it feels like a wonder of the world for…

Wow, I had seen the inside of the refinery still partly under construction way back in 2003 when I was barely out of my teens.

Re: How an oil refinery works

#153

Post by pfdietz »

aethr wrote: post #117
adrianN wrote: post #105

Earlier quoted context omitted.

The problem with carbon capture from air is the low carbon concentration. Try to do the math for how much air you need to process to get even one barrel of oil worth of hydrocarbons from a DAC process.

The answer to this problem as it's currently being pursued is renewable carbon feedstocks. Growing things like canola on marginal land, harvesting it and turning it into biofuels and LCLFs (low carbon liquid fuels) using renewable solar/wind energy. It's not a solved problem, though. Truly renewable carbon feedstocks have to source their carbon from the air, not the soil, which has to be continually measured. Land se…

Remarkable amounts of carbon are available in waste streams, even if you exclude from the count plastics and other petrochemicals. Paper, cardboard, wood, natural fibers, carbon in sewage and waste food, and especially farm waste (parts of plants not otherwise consumed). Some of the latter is needed for soil conditioning, but most of that is from decay of roots, not stuff left at the surface.

All this can be extended by addition of hydrogen. Naively, if you process a carbohydrate into hydrocarbons, about half the carbon is lost as CO2. Adding hydrogen allows the oxygen to be carried off as water rather than CO2 (or, the CO2 to be converted to hydrocarbons and water in a second step.) Hydrogen currently comes from natural gas but that will have to change anyway, with the hydrogen being produced by (for example) electrolysis of water.

Re: How an oil refinery works

#154

Post by arethuza »

pjc50 wrote: post #136
jyounker wrote: post #135

Earlier quoted context omitted.

Wow. I grew up in Houston, and I assumed that the smell from these plants was pretty-much unavoidable. It's shocking (and I guess not all that surprising) that this is a choice that manufacturers make. I guess it really does depend on the economic power of the surrounding communities.

Where I live there's been a long running saga around flaring: https://www.bbc.co.uk/news/topics/c6wk2ml6gwzt When it's lit at night you can see it from up to twenty miles away. Closer in you can hear it. Things have gone back and forwards on mitigations, fines, industrial disputes, and in the end the plant is closing.

When we lived in Edinburgh our flat had a fantastic view north - which included the spire of Fettes College and occasionally the flare from Mossmorran - which together look quite like Barad-dûr and Mount Doom...

Re: How an oil refinery works

#155

Post by pfdietz »

marcosdumay wrote: post #92
nerdsniper wrote: post #14

Earlier quoted context omitted.

To me (as someone who has worked on oil rigs, oil pipelines, oil refineries, and chemical plants), crude oil seems far more valuable as a material than as an energy source. It feels like a damned shame that we're still combusting so much of it for heat rather than reserving it for physical materials. I understand the ways that economics are very important, and that the economics still currently favor burning a large…

There is way more carbon in the ground as rocks than as oil. If you have plenty of energy, the difference is quite manageable. Besides, as somebody already pointed out, there is that CO2 on the air that we actually want to get rid of. It's nothing compared to the rocks, and a little harder to get, but getting it first would improve things a lot.

The density of carbon in seawater is also higher much than it is in air. The relative concentration of bicarbonate in seawater is a few times lower than in air (as % by mass), but because water is nearly 1000x the density of air the true amount of bicarbonate there per volume is much higher.

Re: How an oil refinery works

#156

Post by throwaway173738 »

jyounker wrote: post #141
cucumber3732842 wrote: post #90

Earlier quoted context omitted.

Gotta love that ivory tower smarmy attitude. >And it requires so much "ground" to properly "filter", hence the mounds. There is no point in building up if the ground is sufficient. MN has basically decided they're not gonna bother considering what that means and just make everyone do mounds at great expense. >So we both agree there's a high water table, and high water tables can give challenges for properly operating…

> Gotta love that ivory tower smarmy attitude. When did, "I don't want people poisoning my water," become ivory tower smarmy attitude?

It was the tone of the reply, I would imagine.

Re: How an oil refinery works

#157

Post by pfdietz »

yread wrote: post #37

I find it amazing how "naphtha" can mean crude oil, diesel, kerosene, gasoline or kind of white spirit. EDIT: oh and it comes from Akkadian! how many Akkadian words do you know?

That etymology is fascinating, thanks.

Re: How an oil refinery works

#158

Post by pfdietz »

sushibowl wrote: post #68
didgetmaster wrote: post #61

I remember driving by a refinery years ago and it had two or three towers with big flames that were just burning off waste gas. This seemed wasteful to me. If it can burn, then it seems like it could be used for something productive. Do they still just burn off that gas?

Usually, when refineries flare something like that it's because what they are burning is not suitable for use, and making it suitable would cost more than the product would sell for. Often methane as a by-product of oil production is flared, because the amount is small enough that it's not worth setting up processing plants and supply chains for. Other times, the fluid is heavily contaminated by e.g. sulfur compounds…

> Although, flare gas recovery systems exist nowadays to make use of these waste gases, commonly for local power production for the refinery itself.

Cogeneration like that is huge. When PURPA was passed in 1978 requiring utilities to buy cogenerated power it was a major reason for the end of the first wave of nuclear power plant construction in the US.

Re: How an oil refinery works

#159

Post by throwaway173738 »

next_xibalba wrote: post #96

> an astounding 90% of chemical feedstocks are derived from oil or gas What I often wonder is, as the demand for oil declines, the economies of scale in oil production should, too. If that is the case, will not the price of everything with oil byproduct inputs go up? In other words, will the transition to other energy sources actually be highly inflationary?

Maybe. It might also require not using as much disposable stuff in favor of reusable things. The culture we’ve built around disposable plastics and such is less than 100 years old. Our great grandparents lived considerably differently.

Re: How an oil refinery works

#160

Post by pfdietz »

beerandt wrote: post #76
sushibowl wrote: post #68

Earlier quoted context omitted.

Usually, when refineries flare something like that it's because what they are burning is not suitable for use, and making it suitable would cost more than the product would sell for. Often methane as a by-product of oil production is flared, because the amount is small enough that it's not worth setting up processing plants and supply chains for. Other times, the fluid is heavily contaminated by e.g. sulfur compounds…

Yea while $ viability is true, it's better to think of as 1) using some potentially useful products as fuel to burning off things you don't want and 2) the buffer to keep non-steady inflows in a suitable ready condition for steady-state processing. (When real world steady-state is less than ideal.) Number 2 is really what dominates the equation, as shutting in gas sources or even just turning off pipelines is incredi…

There are large storage facilities for natural gas (underground, often in depleted gas fields or solution mined from salt formations) that buffer changes in consumption. These enable pipelines to operate efficiently even when demand is going up and down with the seasons.
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