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A CO2 capture solvent with exceptionally low total costs of capture

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Re: A CO2 capture solvent with exceptionally low total costs of capture

#261

Post by jjk166 »

petra wrote: post #199
thechao wrote: post #141

Earlier quoted context omitted.

I don't know why the Democrats, in particular, don't turn this into political hay: it's literally the perfect counter to the coal issue. 1. Olivine is plentiful, everywhere, including as the tailings from huge defunct coal mines; 2. All of the mining & transportation infrastructure is already in mining country; 3. Mining country is desperate for solid, dependable blue collar work; and, 4. Mining country already has e…

It's not enough to change people's beliefs about climate change and political choices. >> Olivine is plentiful, everywhere, That means olivine will be mined everywhere. not necessarily in coal country.

Coal country has a comparative advantage due to the already existing infrastructure and expertise that others would need to acquire from scratch.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#262

Post by jjk166 »

xyzzy21 wrote: post #237

What's the energy consumption to make this moderately complex organic compound? If it takes more energy (largely generated from fossil fuels - and generating CO2 itself) than it removes... it's not going to be viable. You must have >1:1 otherwise you are better off doing nothing at all.

The compound is a solvent, you reuse it repeatedly, so there is no need for it to be >1:1.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#263

Post by jjk166 »

khuey wrote: post #100
linknoid wrote: post #80

Earlier quoted context omitted.

Maybe you can help enlighten me on this. I've been struggling to understand the basics thermodynamics of carbon capture for quite some time. So we have a hydro-carbon, we mix it with oxygen, and the oxygen combines with the hydrogen and the carbon, and releases heat as a byproduct. The heat energy increases the pressure of the newly created CO2. This higher pressure is placed on one side of a turbine or a piston, and…

Enthalpy of combustion for CH4 is 802 kJ and for an equivalent amount of gaseous hydrogen it's 286 kJ so most of the energy does come from the carbon.

That's not how chemistry works. Burning 1 CH4 is not the same as burning 1 C and 2 H2. The formation of carbon dioxide (aka the combustion of carbon) contributes 393.5 kJ per mole of CH4 combusted, and the formation of water (aka the combustion of hydrogen) contributes 483.6 kJ per mole of CH4, the activation energy to split the CH4 molecule is 74.8 kJ per mole of CH4 combusted. So 55% of the heat released per mole is from the hydrogen.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#264

Post by jjk166 »

linknoid wrote: post #80
iamthemonster wrote: post #13

Earlier quoted context omitted.

1. The solvent in carbon capture runs in a closed loop. You typically heat it, and it releases the CO2 so you can compress it and inject it below ground. 2. You don't necessarily need a depleted natural gas reservoir to inject CO2 subsurface (though they sure are convenient) and there is plenty of room for CO2 subsurface. It also doesn't creep to the surface on any meaningful timescale. 3. How do we transport it ther…

Maybe you can help enlighten me on this. I've been struggling to understand the basics thermodynamics of carbon capture for quite some time. So we have a hydro-carbon, we mix it with oxygen, and the oxygen combines with the hydrogen and the carbon, and releases heat as a byproduct. The heat energy increases the pressure of the newly created CO2. This higher pressure is placed on one side of a turbine or a piston, and…

Expanding on what others have noted:

Heat engines take advantage of the fact that expanding a hot fluid releases more energy than it takes to compress a cold fluid - the difference being that combustion energy. Indeed the pressure difference is only there to make the process more efficient - so long as there is a temperature gradient you can extract energy even with no pressure gradient.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#265

Post by jjk166 »

TedDoesntTalk wrote: post #173
epistasis wrote: post #171

Earlier quoted context omitted.

This is false, energy efficiencies do decrease energy use, in most situations. Jevon's paradox is the exception, not the rule. For example, increasing fuel efficiency of cars does decrease energy use, because fuel cost is not the limiting factor foe most car travel. Similarly, more efficient lighting, more efficient home space heating and water heating, and better weatherization of homes, all increase energy efficien…

As an anecdote: if you take an ant population (or any controllable population), and put it into a confined space with constrained resources, the population eventually dies due to one of two things: 1. Elimination of resources 2. Excessive waste product (in this case, excrement and bodily wastes; pollution)

Yeah, and if the sun turns off and stops pumping 174 PW into our system, we'd be pretty screwed. Luckily we do not live in a confined space with constrained resources.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#266

Post by worldofmatthew »

KptMarchewa wrote: post #214
worldofmatthew wrote: post #204

Earlier quoted context omitted.

I am pretty sure the $0.10 per tree of the Eden reforest project would be far cheaper than $47.10 per ton, to say the least. That would be 471 trees for $47.10.

Does the 0.10$ include land acquisition for the forest? If not, the cost could be significantly higher.

They work with the native communities (that is why around 10% of trees planted are designed as a food source) which allows that 10 cents to cover everything, not just the planting of the trees.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#267

Post by iggldiggl »

dagss wrote: post #185
aardvarkr wrote: post #148

Earlier quoted context omitted.

This sounds like hyperbole but it’s the honest truth. Billions would die due to food shortages. Our modern farming system is incredible at its job of feeding 7 billion people.

...and yet 1/3rd of the food is thrown away/perish globally. There is a lot of excessive waste / inefficiencies due to energy being -- relatively -- cheap. If energy prices soar, many inefficiencies will get more attention. Like, if food becomes more expensive we would stop throwing away 1/3 of it. (And more houses would get proper insulation. And so on.)

At least part of which is a necessary hedge against possible years with a bad harvest, though. A temporary shortage of toilet paper or even microchips is one thing, but you most certainly wouldn't want the same thing to happen with your food supply.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#268

Post by fnord77 »

api wrote: post #234
occz wrote: post #233

Earlier quoted context omitted.

Any true malthusian will of course voluntarily take the first step and remove themselves. Right?

Scratch a Malthusian and you will find either a pure misanthrope or a racist. In either case the solution is always for others to die.

> a pure misanthrope

you rang?

> In either case the solution is ...

well, thinking about it, no solution is also a good solution.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#269

Post by JohnL4 »

galangalalgol wrote: post #190
stephanheijl wrote: post #6

I've been looking at the use of algae with regards to sequester img CO2 from the atmosphere. This seems to have some remarkable advantages: single molecules which make mass production easier, presumably less finicky operating procedure and way more straightforward to pump into disused oil wells. From the abstract it does seem to need CO2 being supplied to it as opposed to drawing it from the atmosphere actively. I as…

I'm interested in causing algae blooms near the equator with iron sulfide. Not for co2 capture, most of that would get released on decomposition, but for the albedo effect. It also has the failsafe that if it gets too cold the algae will die preventing a snowball earth. They did some tests for salmon production, and scaling that linearly for area covered it would be less than a $1.5 billion project. Also we get salmo…

Within striking range for any single trillionaire.

Reminds me of this article (which also mentions algal blooms): http://www.theatlantic.com/magazine/archive/2014/09/how-to-t...

«Few experts think that relying on geo-engineering would be a good idea. But no one knows how soon reality will trump ideology, and so we may finally have hit on a useful form of alarmism. One of the virtues of Keith’s succinct, scary book is to convince the reader that unless we find a way to talk about climate change, planes full of sulfuric acid will soon be on the runway.»

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