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Solving climate change by abusing thermodynamic scaling laws

ckrapu.github.io

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Re: Solving climate change by abusing thermodynamic scaling laws

#41

Post by ckrapu »

ospray wrote: post #9

The globe is mostly water. Ocean fertilization make a lot more sense than this for a whole bunch of reasons. The inter-continental sea floor automatically freezes all carbon that goes down there most of it is stored as methane. Just need a fleet of nuclear powered fertilizer ships to kick it off hopefully you get more fish as a result. https://en.m.wikipedia.org/wiki/Ocean_fertilization

One downside: you have to ship all the carbon to the coast. Transport is a non-negligible consideration for all of this. Ideally, you just grow a ton of switchgrass in northern US / Canada / Siberia and store it nearby.

Re: Solving climate change by abusing thermodynamic scaling laws

#42

Post by pstrateman »

FooBarBizBazz wrote: post #35
pstrateman wrote: post #33

Earlier quoted context omitted.

Simple math unfortunately. To offset global human CO2 production you'd need to biochar all plant matter several times a year.

This feels like a "yes, and" thing, where the most important use of effort is to reduce production (and we're nowhere close yet), but at some point we'll need to also do capture to deal with production that is truly unavoidable, and, if we're dreaming, to achieve net negative production, for the purpose of returning to preindustrial levels. But yeah, if you're burning coal with one hand and making charcoal with the o…

Reducing production is simply impossible.

There's billions of people on earth who are desperately poor compared to even the poorest American.

There is absolutely no chance those people just accept their position as ultra poor.

If individuals want to reduce their CO2 output the only viable strategy is to buy and permanently store fossil fuels.

Re: Solving climate change by abusing thermodynamic scaling laws

#43

Post by philipkglass »

Retric wrote: post #20
philipkglass wrote: post #7

I'm going to share my own insane idea for drawing down atmospheric CO2. Capture CO2 as biomass or with direct air capture. Pyrolyze biomass to charcoal or use the Bosch reaction to recover pure carbon from CO2 chemically [1]. Then combine the carbon with silicon to form silicon carbide via the Acheson process: https://en.wikipedia.org/wiki/Acheson_process Silicon carbide is extraordinarily resistant to mechanical ero…

Not all life is connected to earths atmosphere. That that doomsday weapon is missing caves which contain multicellular life across geologic timescales. The ecosystems dependent on chemical synthesis at deep ocean vents would similarly be unaffected. You might kill off plants though frozen seeds are viable for an extended period, but the incoming ice age is going to preserve aglee until atmospheric CO2 returns to norm…

The incoming ice age could be averted by simultaneously adding carbon-free greenhouse gases like nitrous oxide to the atmosphere, but I suppose that kills the "solving global warming" part of the pitch.

Not all life is connected to earths atmosphere. That doomsday weapon is missing caves which contain multicellular life across geologic timescales. The ecosystems dependent on chemical synthesis at deep ocean vents would similarly be unaffected.

That's a good point and I don't see a way around it.

Re: Solving climate change by abusing thermodynamic scaling laws

#44

Post by ckrapu »

philipkglass wrote: post #43
Retric wrote: post #20

Earlier quoted context omitted.

Not all life is connected to earths atmosphere. That that doomsday weapon is missing caves which contain multicellular life across geologic timescales. The ecosystems dependent on chemical synthesis at deep ocean vents would similarly be unaffected. You might kill off plants though frozen seeds are viable for an extended period, but the incoming ice age is going to preserve aglee until atmospheric CO2 returns to norm…

The incoming ice age could be averted by simultaneously adding carbon-free greenhouse gases like nitrous oxide to the atmosphere, but I suppose that kills the "solving global warming" part of the pitch. Not all life is connected to earths atmosphere. That doomsday weapon is missing caves which contain multicellular life across geologic timescales. The ecosystems dependent on chemical synthesis at deep ocean vents wou…

A flawed doomsday weapon but a good mechanism for building a fictional world where the biosphere develops underground.

Re: Solving climate change by abusing thermodynamic scaling laws

#45

Post by ckrapu »

jacknews wrote: post #5

Or just burn the huge piles to charcoal (pyrolysis), then you're only storing carbon, and it certainly won't decay. Even use it as a soil enhancer.

Let's say that we have a hollowed-out zone in the middle of the biomass pile where we tolerate limited oxidization so we can run a fire. If the rest of it is wet, maybe the heat from that combustion could pyrolyze a large radius of surrounding material since O2 flow into the system should be small.

Re: Solving climate change by abusing thermodynamic scaling laws

#46

Post by schiffern » 

  >we avoid most capital expenditures... since no provision must be made for moisture management or geotechnical engineering
No summer rains in this (presumably agricultural) project area?

I see no math for heat transfer due to rainwater percolation through the pile. "Assuming all voids are filled with water" is great and all, but (with apologies to Jurassic Park) water... uh... finds a way. Meltwater will even tunnel its way through compacted glacial ice.

Plus the "dry" insulation layer won't stay dry for long.

Re: Solving climate change by abusing thermodynamic scaling laws

#47

Post by ckrapu »

schiffern wrote: post #46

>we avoid most capital expenditures... since no provision must be made for moisture management or geotechnical engineering No summer rains in this (presumably agricultural) project area? I see no math for heat transfer due to rainwater percolation through the pile. "Assuming all voids are filled with water" is great and all, but (with apologies to Jurassic Park ) water... uh... finds a way. Meltwater will even tunnel…

Good catch :)

I thought about this for awhile and the gap between harvest time for many crops and first frost isn’t enough to get more than a few inches of rainfall in most agricultural regions with favorable economics.

I think the wetness will wreck the insulation of the first meter or so, but won’t lead to much convective heat transfer if the outside never gets saturated. A big if, to be sure.

As an aside, it’s common practice to leave large piles of grain outside overwinter in the central USA and it’s not optimal, but they certainly don’t saturate the whole way through with water.

Re: Solving climate change by abusing thermodynamic scaling laws

#48

Post by schiffern »

ckrapu wrote: post #47
schiffern wrote: post #46

>we avoid most capital expenditures... since no provision must be made for moisture management or geotechnical engineering No summer rains in this (presumably agricultural) project area? I see no math for heat transfer due to rainwater percolation through the pile. "Assuming all voids are filled with water" is great and all, but (with apologies to Jurassic Park ) water... uh... finds a way. Meltwater will even tunnel…

Good catch :) I thought about this for awhile and the gap between harvest time for many crops and first frost isn’t enough to get more than a few inches of rainfall in most agricultural regions with favorable economics. I think the wetness will wreck the insulation of the first meter or so, but won’t lead to much convective heat transfer if the outside never gets saturated. A big if, to be sure. As an aside, it’s com…

Beyond that gap time period, I was thinking more about longer-term storage and heat transfer. What happens over the second summer?

Grain piles have free drainage so we don't expect saturation, but if water freely drains through this system it seems problematic.

Re: Solving climate change by abusing thermodynamic scaling laws

#49

Post by specialist »

philipkglass wrote: post #7

I'm going to share my own insane idea for drawing down atmospheric CO2. Capture CO2 as biomass or with direct air capture. Pyrolyze biomass to charcoal or use the Bosch reaction to recover pure carbon from CO2 chemically [1]. Then combine the carbon with silicon to form silicon carbide via the Acheson process: https://en.wikipedia.org/wiki/Acheson_process Silicon carbide is extraordinarily resistant to mechanical ero…

Love it. I'm firmly in the Yes And camp.

Could you also produce for the sizeable and growing SiC market? It'd be cool if your source was competitive (assuming green H2 level subsidies).

--

As you know, once we achieve net-zero (2050), we'll have to accellerate into net-negative. From the hip, maintaining current growth of renewables (17% YoY), we'll cover expected demand 2045-2050. Then what?

Methinks each and every carbon sequestion idea and strategy should be attempted. Like starting with obscene funding amounts for yearly DARPA style x-prizes. Winners advance to the next round.

And hopefully some of the strategies are scaling in time to soak up the excess production.

Re: Solving climate change by abusing thermodynamic scaling laws

#50

Post by gus_massa »

philipkglass wrote: post #7

I'm going to share my own insane idea for drawing down atmospheric CO2. Capture CO2 as biomass or with direct air capture. Pyrolyze biomass to charcoal or use the Bosch reaction to recover pure carbon from CO2 chemically [1]. Then combine the carbon with silicon to form silicon carbide via the Acheson process: https://en.wikipedia.org/wiki/Acheson_process Silicon carbide is extraordinarily resistant to mechanical ero…

> But if you have the Sahara-sized robotic solar farm and industrial complex to put it into practice, it makes a great doomsday weapon!

1) Can the other side just nuke most of it?

2) Isn't it cheaper to build a few thousand nukes instead of a Sahara-sized solar farm?

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