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karimwassef
10/01/2017, 12:20 PM
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I couldn't help but think that this is just using a kalk solution to "trap" CO2 and then using the Calcium Carbonate "salt" to make paper (which is pretty standard)...

Also - wouldn't large algae vats do just as well in a desert?

bertoni
10/01/2017, 07:25 PM
It could use Kalk, or possibly lye. They say that they are converting the carbonate back into carbon dioxide and Kalk-lye, so I don't think they are making paper with it. They also discuss turning the carbon dioxide into hydrocarbons. If it turns out to be a financially viable way to produce carbon dioxide or hydrocarbons, it might be useful, but I don't know how feasible that might be in the end.

orcafood
10/02/2017, 08:48 AM
CO2 removed from the emission source would be way more efficient over removing it from thin air. I bet they are using soda lime, CaOH2 with catalytic NaOH. Since energy is lowered when CO2 forms carbonate ie spontaneous, wouldn't energy need to be added to release the CO2?

Usually to make hydrocarbons they would do it step by step, first CO2 would go to CO via some catalyst then it would be separated out. A variety of well known reactions can be used to try and generate hydrocarbons under intense pressure over catalyst beds from the carbon monoxide. Beating out syngas with a photocatalyst to cleave the CO2 to CO is unlikely for the near future. Plants are very very good at fixing carbon and look at how slow they grow. Eventually supply will go down though, demand up, and the prices will come closer. My good friend did this as his final project at NCSU, they took raw syngas and synthesized methanol at a theoretical plant they designed, of course at the lowest possible cost.

karimwassef
10/02/2017, 09:39 AM
They're targeting emissions from vehicles, etc...

I still think growing algae is more efficient

orcafood
10/02/2017, 09:47 AM
I am pretty sure that the ocean is the biggest CO2 sink on the planet, probably from all of the algae growth

karimwassef
10/02/2017, 12:59 PM
Exactly... the earth heals using existing mechanisms.. but the wild algae can disrupt other life (like coral).

If we use large algae vats and convert the algae to energy, we're tapping directly into the energy source and scrubbing the planet.

orcafood
10/02/2017, 02:06 PM
Why not use the ocean as the large vat?

Imagine how much algae the ocean generates over the entirety of the worlds water. Water covers 70% of the earths surface and its probably a very good thing. As we start to build up the plastic heaps floating in the gyres we will start to experience some serious problems from snuffing out all that algae.

I feel like the planet will always be fine. Humans and many other creatures might not be so lucky. But then evolution will just take its course again, more than likely some organisms will survive climate change and thrive/evolve.

Tripod1404
10/02/2017, 03:20 PM
The issue is, what ever fuel you produce from atmospheric CO2 will return there as long as we use it as fuel. On the bright side, it would prevent more CO2 from being added to the atmosphere, but it can not be done at a rate that would reduce the CO2 levels while still being used as a fuel. That would mean producing more fuel than we are using.

The issue with using algae in vats is; it is more efficient to use land plants. Most land plants are better at fixing CO2 anyways, and they need far less water than any algae. Oceans contribute to 50% of global oxygen production while surrounding 2/3 of the surface. Land plants contribute to the other 50% while only having 1/3 of the total surface.And in actuality some part of that 1/3 is also not usable, such as deserts, tundra and etc.

Currently, it is more efficient to ferment non-edible parts of crop plants into bio-ethanol (such as leaves of maize and rice).

One proposal for removing atmospheric CO2 involves burying all these "non-edible plant" stuff into expired coal mines. A more extreme measure can even be growing forest (ideally a rapidly growing tree), cutting the trees and burying them into coal mines and repeating this over and over again using the same land. That will put carbon out of carbon cycle and reduce CO2 levels. But no one is doing this since it has no economical value.


But keep in mind burning a wood fireplace is more environmentally friendly than a gas fireplace since it atleast produce CO2 from a tree that was part of carbon cycle rather than from natural gas that is made of carbon that was not part of carbon cycle for at least millions of years. With the same logic, if we were to turn all coal power plants into wood burning power plants with artificial forests grown just to supply these, there will be no net CO2 input to the air.

bertoni
10/02/2017, 05:51 PM
I agree that releasing the carbon dioxide from the carbonate should require energy, although I have no idea how much.

Using the ocean to remove oxygen requires some study. Many parts of the ocean seem to be iron-limited as far as photosynthesis rate, and there have been experiments on using iron additions to increase phytoplankton growth. I don't know whether the question as to how much of the carbon uptake is sequestered has any answers. Maybe Google will turn up some more information.

karimwassef
10/03/2017, 12:13 AM
Kelp can grow at 1ft per day. That's massive carbon sequestration. It can't be grown in vats, so they're experimenting will field trials in controlled parts of the ocean.

Tripod1404
10/03/2017, 01:05 PM
Kelp can grow at 1ft per day. That's massive carbon sequestration. It can't be grown in vats, so they're experimenting will field trials in controlled parts of the ocean.

Bamboo can grow 3 ft in a day. And being a land plant is much more "carbon" and much less water compared to kelp.

karimwassef
10/03/2017, 04:17 PM
Dedicating land competes with crops.
The ocean has more unfarmed space.

dkeller_nc
10/04/2017, 11:25 AM
Ultimately, growing algae in the ocean is not a practical solution. Neither is growing terrestrial forests. The basic problem is that neither sequesters carbon for the long-term. In the case of terrestrial forests, the sequestration ended with the evolution of higher-order fungi some 400 MYA.

The only way to really remove carbon from the global cycle is mineralization (typically, as calcium carbonate). That can be done by certain simple organisms in the ocean, or it can be done by abiotic means.

But overall, removing CO2 from the atmosphere in its incredibly diluted form takes FAR more energy than removing it at the source of combustion, or not generating it in the first place. Rather unfortunately, that last one isn't a practical option, at least to supply the base load demanded by human civilization.

karimwassef
10/04/2017, 11:43 AM
So corals are the ultimate carbon sequestration organisms?

orcafood
10/04/2017, 12:05 PM
I was under the assumption that some of the algae in the ocean ends up as carbonate detritus, floating to the bottom eventually. If carbonate precipitation truly is the best way to sequester carbon the outlook is not good.

Isn't it interesting how oil deposits stopped being produced once higher order fungi developed? Lignan consumers provided a very important aspect to the history of the planet, suddenly no more oil was developed or ever will be through the same mechanism (can't say 'ever will', genetics is a powerful tool. A fungi could easily be developed that doesn't consume lignan). (Might even exist today :))

The obvious answer is to stop burning the carbon we dig up. Good luck convincing the societies (every society) dependent on coal/oil/dugupcarbon

karimwassef
10/04/2017, 12:29 PM
Need to pour more concrete...

Tripod1404
10/04/2017, 12:55 PM
Ultimately, growing algae in the ocean is not a practical solution. Neither is growing terrestrial forests. The basic problem is that neither sequesters carbon for the long-term. In the case of terrestrial forests, the sequestration ended with the evolution of higher-order fungi some 400 MYA.

The only way to really remove carbon from the global cycle is mineralization (typically, as calcium carbonate). That can be done by certain simple organisms in the ocean, or it can be done by abiotic means.

But overall, removing CO2 from the atmosphere in its incredibly diluted form takes FAR more energy than removing it at the source of combustion, or not generating it in the first place. Rather unfortunately, that last one isn't a practical option, at least to supply the base load demanded by human civilization.

You can remove carbon from the global cycle by burying trees from the artificial forests under ground. Ideally old and dry coal mines. The reason why this stopped happening naturally is the rate of decomposition of wood by fungi and bacteria is much faster than rate of sedimentation.

Like you said before, fungi and bacteria that evolved to decompose wood made it almost impossible for this process to happen naturally at a scale it was in carboniferous period. But still, there are coal mines that are younger than 400MYA. If the wood somehow ends up in a unusual place that these fungi and bacteria cannot live, it can still turn into coal. Most common places that this still naturally happens is under tundra permafrost, bottom of highly anoxic lakes and inner seas.

Overall, I know nobody will grow forests and than bury them since there is no economical value for that. But we can grow forests and use them as a source of energy. If we switch all coal power plants around the world to wood burning power plants (which should be relatively easy conversion), we would not put carbon back to the atmosphere from a source that was taken out of the carbon cycle hundreds of millions of years ago. That would make energy production carbon neutral.

Tripod1404
10/04/2017, 01:01 PM
I was under the assumption that some of the algae in the ocean ends up as carbonate detritus, floating to the bottom eventually. If carbonate precipitation truly is the best way to sequester carbon the outlook is not good.

Isn't it interesting how oil deposits stopped being produced once higher order fungi developed? Lignan consumers provided a very important aspect to the history of the planet, suddenly no more oil was developed or ever will be through the same mechanism (can't say 'ever will', genetics is a powerful tool. A fungi could easily be developed that doesn't consume lignan).

The obvious answer is to stop burning the carbon we dig up. Good luck convincing the societies (every society) dependent on coal/oil/dugupcarbon

Yeah it would be extremely simple to generate a fungi that doesn't consume lignin. The problem is, it would be out competed by fungi that can do it. So even if you release this genetically modified fungi to the wild, it will either go extinct, or it will regain its ability to digest lignin by crossbreeding with related fungi that can do it.

karimwassef
10/04/2017, 01:04 PM
So low cost sps farming is the answer :D

Now if only the market was bigger...

orcafood
10/04/2017, 01:38 PM
Efficient energy storage and an excellent recycling program for necessary metals

orcafood
10/04/2017, 01:42 PM
Yeah it would be extremely simple to generate a fungi that doesn't consume lignin. The problem is, it would be out competed by fungi that can do it. So even if you release this genetically modified fungi to the wild, it will either go extinct, or it will regain its ability to digest lignin by crossbreeding with related fungi that can do it.

I'd imagine rather than releasing it to the wild, it would be cultivated in giant fields/vats of rotting agricultural byproducts. No lignan makes processing the rest much easier. Not that this would solve anything haha. You don't think there is a way to make them win out?

How else are mushrooms commercially grown in the presence of natural trichoderma during fruiting which is in a septic environment?

Tripod1404
10/04/2017, 01:46 PM
I'd imagine rather than releasing it to the wild, it would be cultivated in giant fields of rotting agricultural byproducts. No lignan makes processing the rest much easier. Not that this would solve anything haha.

How else are mushrooms commercially grown in the presence of natural trichoderma during fruiting which is in a septic environment?

How would you prevent other fungi from colonizing those fields? As long as there is undigested lignin, those fungi will come.

orcafood
10/04/2017, 01:47 PM
How do people grow mushrooms and have the fruits not rot before they are picked?

Tripod1404
10/04/2017, 02:52 PM
How do people grow mushrooms and have the fruits not rot before they are picked?

The fruit is the reproductive body of the large underground fungi colony (which can be quite massive). It wont rot because it is alive and connected to the colony. It is the same reason why a healthy apple wont rot on an apple tree. If you dont collect it, after it serves its purpose, it will rot.

orcafood
10/04/2017, 02:54 PM
I guess I am assuming a healthy mycelium could fend for itself. I suppose there would be many many factors at play though.

When growing mushrooms the whole idea is to out-compete other ubiquitous, faster growing fungi.

wertoiuy
10/04/2017, 02:55 PM
Math time!

First of all, using forests to produce biomass is actually a really poor strategy, as newly growing forests of fast-growing trees are poor at sequestering carbon. Forests are amazing carbon sinks, but only for mature, slow-growing forest. This is due to the massive amount of biological diversity provided by this environment, most of which isn't included in biomass. Land is much better used as forested habitat than as farmed forest. Biomass production is most effective with typical crops such as corn and wheat. About 60% of the biomass comes from the grain portion.

So for conversion of coal and natural gas powerplants to consume biomass:
- 66% of power comes from coal and natural gas.
- 66% of US energy consumption (adjusted for use in gas-burning heaters as well as powerplants) is 4,419,360,000 Gigajoules/year.
- Each ton of typical non-tree biomass produces 3.7 gigajoules
- 1,194,400,000 tonnes of biomass/year therefore necessary to meet demands
- This needs 173,100,000 acres of land farming corn in addition to that which already is farmed to meet food demands (current land usage for corn farming is 90,000,000)
- This translates to 270000 square miles, or roughly the size of Texas
- This is just for the US, which has one of the lowest population densities in the world. Countries such as India, China, and most of Western Europe are heavy polluters with little land left to spare.

Perhaps algae, kelp, or bamboo could be more efficient, but I don't believe it would be enough. Personally I like solar panels installed on house roofs, and just placed in the deserts of the Southwest. Ultimately, what it boils down to though: There are WAY too many people and none of them live very efficiently.

dkeller_nc
10/05/2017, 09:29 AM
Yep. This is the issue with most carbon sequestration schemes, as well as the idea of "get the base load from solar power". It's not that the basic idea isn't technically correct, it's the that the math just doesn't work out.

Certainly some of the US's peak load demands can be supplied with wind/solar/biomass combustion. But the base load demand is far too high to make those sources practical. Just a quick back-of-the-envelope calculation for base load generation by means of solar power would lead one to the conclusion that you'd need to cover Arizona with solar cells. Never mind the environmental degradation from the mining and refining of the minerals required to make all of those solar arrays.

Rather unfortunately, most optimistic declarations that I see in regards to renewable generation at large scale leaves out careful analysis that includes all factors. One such omission that's extremely common is neglecting line losses that occur in generating electricity and delivering it via grid systems to distant consumers. Such a system would be necessary to deal with the power demands of unfavorably located population and industry (such as the northern US).

orcafood
10/05/2017, 02:14 PM
I agree solar cells will require serious recycling programs because the amount of mining and transition metals necessary. Imagine if wires could be come up with that had no resistance. Game over, humans win. Or perhaps an efficient battery, now no more motorized cars/engines. Digging up transition metals efficiently will become very important for energy storage and transmission. Then imagine how efficiently we will need to recycle the metals. Completely impossible with today's global mindset.

Yep. This is the issue with most carbon sequestration schemes, as well as the idea of "get the base load from solar power". It's not that the basic idea isn't technically correct, it's the that the math just doesn't work out.

Certainly some of the US's peak load demands can be supplied with wind/solar/biomass combustion. But the base load demand is far too high to make those sources practical. Just a quick back-of-the-envelope calculation for base load generation by means of solar power would lead one to the conclusion that you'd need to cover Arizona with solar cells. Never mind the environmental degradation from the mining and refining of the minerals required to make all of those solar arrays.

Rather unfortunately, most optimistic declarations that I see in regards to renewable generation at large scale leaves out careful analysis that includes all factors. One such omission that's extremely common is neglecting line losses that occur in generating electricity and delivering it via grid systems to distant consumers. Such a system would be necessary to deal with the power demands of unfavorably located population and industry (such as the northern US).

karimwassef
10/17/2017, 08:33 PM
back to... ALGAE to save the planet (carbon sequestration + later can be used for energy production later with CO2 recapture)

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ALGAE oil to JET fuel

Frogmanx82
10/19/2017, 06:38 PM
CO2 is necessary for life. If humans hadnít come along to release it the planet would eventually have died out from a carbon shortage. See my sig. Free the Carbon!