The crushing rock works very slowly - that part of the carbon cycle takes ages. Any significant speedup of that would also be an environmental disaster - again too much rock crushing, and it would have to be spread over large areas.
Even worse, this will all need to be done in an already deteriorated planet, with almost assuredly worse political stability and real economic output than we have now.
What you are describing is how technological progress works usually. We first typically learn to do something at small scale, then learn to solve problems that are necessary to scale it up.
The problem isn't really whether we can do it but whether we can get people to be willing to do it.
> The crushing rock works very slowly
Yes, it does. But once you crush the rock the rest happens on its own while you are crushing even more of it. Which means after some time the removal will asymptotically reach the speed at which you are able to crush the rock (and supply the air).
Also, I think you are just flat wrong about how unprecedented this operation would be. Digging oil and coal from under the sea or thousands of meters below ground is certainly more difficult than crushing rock that is readily available on the surface basically everywhere.
I think the bigger issue is figuring out what to do with that crushed rock so that it has contact with air so that it can actually perform the reactions we want (this might not be solvable).
We can use crushed rock to some extent. For example, I use powdered basalt in my garden. It improves the soil and provides nutrients over long periods of time. But I think we would quickly run out of agricultural soil to fertilise this way.
Also, no, I'm not wrong about the scale. This solution would require orders of magnitude times more mass than the oil/coal extraction you're describing. Again, you still aren't grasping how big this would be. It would require giant open pit mines to take out literal cubic kilometers of rock, and keep doing this for ages.
You seem to be very sure about knowing what I can or cannot grasp. You wield this sentence as some kind of weapon against me but the fact is you are not presenting any arguments.
Humanity has shown that it can do a lot if it just wants.
Look at the scale of world wars where large part of world's output was converted to war effort because we just didn't like the idea of being conquered by Nazis.
The great pyramid of Giza is 0.2% of cubic kilometers and it was literally built with sticks and rope, for vanity, with relatively few people.
Your claim that humanity can't crush a bunch of cubic km of rock and spread over vast areas of land when faced with existential crisis is shortsighted.
I keep saying "you don't grasp" the scale here because really you don't. Myself and others have explained how enormous this undertaking would be, but you haven't given any kind of solution to the manifold problems we outlined.
BTW, I worked as mechanic on heavy equip, crushers, drills, and haulage at many mines.
Your low energy solution isn't.
Yes, we only need to produce more fertilizer than we ever have and keep doing that year on year forever.
>as silicate is weathering it will naturally extract CO2 and the question is how efficiently you can powder rock.
We only need to mine an Everest worth of stone each year for a millennium or so.
Yes. Such achievable goals.
The only ones that come close to being reasonable is dispersing aerosols in the upper atmosphere and reducing the sunlight that reaches the ground directly. That has the problem that we need sunlight for such pesky things like photosynthesis.
Another possible solution would be finding a process that will remove CO2 as a byproduct. If you have to put a lot of energy into it, at least get some part of it back.