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Carbon Capture and Sequestration 8

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awhicker84

Mechanical
Apr 9, 2013
93
Hi all,

Is there a forum on this community dealing with carbon capture and sequestration?

This is a huge potential industry and we need it. I'd like to read up on the current engineering problems and solutions.

Thanks and cheers,

 
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Gasifying coal doesn't eliminate the "sulphur problem"- it merely makes the sulphur easier to catch in a sense. Every molecule of S in the feed coal still needs to end up removed as some other form of sulphur, and that takes energy AND results in emissions. There is nothing inherently "clean" about gasification- rather, the downstream needs for the resulting syngas usually require purification of the syngas which drives the resulting emissions.
 
I'm all for clean energy.

I'm all for carbon capture and sequestration.

Let's do it all. Like you say, we don't have the political will. Half the population thinks there is a debate in the scientific community on whether CO2 created by humans is causing global warming. It's going to be hard to get political will in that climate.

It would be really exciting if the US treated CO2 elimination and capture as the next manned mission to the moon.

Some of the carbon capture techniques can be used to replace products. One person created self healing concrete and another person found a way to create bricks using the same technique. Basically, the brick thing would save hundreds of millions of tons of CO2.

I think we are screwed. I don't think people will realize the damages they've done until it is too late to reverse it. But who knows, maybe this problem will become the next space race.

 
Sorry to burst your bubble, but none of the concrete/brick examples you gave are actual NET removers of CO2 from the atmosphere. Cement starts out as carbonate rocks- and all that carbonate is driven off as CO2 during the calcining process. All these guys are doing is returning a little of that CO2 to the resulting cement in place of water of hydration- a little more and a lot faster than happens in the normal, ~ 100 yr curing process for cement products.

There is some limited geological capacity for carbon sequestration, i.e. some holes available to stuff CO2 into, and some capacity for converting olivine and serpentine to magnesite etc.- but the accesible amounts of these minerals is a tiny fraction of the amount of CO2 we're dumping into the atmosphere from fossil sources.

I hear you- it's an important problem, so you want us to do everything we can. I want us to think about what is possible and practical first, and not be distracted by non-solutions. Carbon sequestration is a non-solution. It's worse than merely being a dead end- it's a distraction being deliberately used by people who like the status quo and want to keep doing it longer.
 
I agree they aren't net removers. They help us to be able to control CO2 better. Nothing wrong with that.

 
Half the population thinks there is a debate in the scientific community on whether CO2 created by humans is causing global warming. It's going to be hard to get political will in that climate.

Interesting irony. You dismiss the notion that there is a debate, yet gripe about lack of progress. IME until you have an open-minded debate there is no progress.

In reality there are multiple debates in this realm including our species' total technology vs natural impact, the impact of one "greenhouse gas" vs another, etc. Many believe that hydrocarbon emissions are by far the worst for our atmosphere, even within the EPA, yet the EPA still pushes this notion that natural gas is a "clean" alternative to other fuels. Working in engine development, the other personal irony for me is that automobiles and combustion powerplants are commonly believed to be a source of air pollution within our cities yet in many US cities they are actually cleaning air through combustion that is dirtied by human existence otherwise.
 
Haha, sorry I was being too specific. Thanks for catching it.


"Half the population thinks there is a debate in the scientific community on whether GHG's created by humans are causing global warming."

Better?

All I was suggesting was a community for carbon capture and sequestration. Add an entire forum to the engineering behind removing / reducing GHG's if you'd like.

I'd like to move on to technical questions.

Thanks,
 
I'll agree with moving onto technical discussion and will always support subforums being added (and some combined or deleted) as necessary to maintain organization and decent turnover within each subforum. My only point of contention is that your previous posts suggest that 100% of scientists agree that mankind is causing global warming. I dont claim to be an expert in environmental matters but having worked with the EPA and being married to an environmental scientist I can attest there are many qualified folks arguing mankind's role in global warming is either tiny or nonexistent.
 
Simply grow lots and lots and lots and lots and lots of trees, warehouse all of the wood/lumber in a way that it will not decay, and then when the CO2 levels start to swing back the other way and we start to realize that an ice age is imminent, start burning said wood. Simple. The trees could even be harvested the old fashioned way to prevent excess oil consumption by heavy machinery and trucks . . . axes bucksaws, ox carts, etc. The demand for flapjacks and bacon and flannel shirts will skyrocket, helping the farmers, it's win-win all the way around.




It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
 
The only way to haul wood any decent distance is with diesel trucks, though.

The alleged AGW is also contributing to drought conditions in many of the areas would have otherwise been ideal for tree planting, as well as resulting in a year-round fire season. A single season of fires results in the obliteration of years and square miles of tree growth.

However, in addition to drought, the "old-fashioned" way of tree harvesting was clear-cutting, which has resulted in many swaths of earth so eroded that they're no longer fit for trees or much of anything else.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
That was somewhat a tongue-in-cheek post, but in theory it could perform the function necessary. No need to haul great distances if warehousing is the end game. Drought can most definitely be a factor, but there are still plenty of areas of the earth that see substantial rainfall and have soil conditions to support. We are seeing climate change, no doubt, and with that is coming climate shift. Areas that formerly supported forestation may no longer, and other areas, my locality included, are beginning to see wetter summers. Clear cutting is generally a terrible idea, agreed, but thinking of a fast growing species (poplars/alders, willow, etc) which reach harvestable maturity in 5 to 8 years, clear cutting and rotation becomes a do-able strategy. With woody biomass being roughly 50% carbon (dry) by weight, there is clearly some potential.

I still think reducing consumption is going to have to be the clincher, though. With the politics of maintaining a robust economy, this is unlikely to happen on a scale that is palatable to policy makers and the money kings.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
 
"With the politics of maintaining a robust economy"

I wish it were that simple in the US. There's certainly that school of thought, but there are others that simply want to reject that possibility outright, seemingly independent of whether there's some sort of short term benefit.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
Depends on your definition of qualified I guess
There's highly qualified folks on both sides of the issue. The challenge to arriving at a correct conclusion is that they're working on quite literally the world's largest engineering problem with an astronomical number of variables, in an open system, with inputs that still aren't well understood. Even our greatest minds can only work on one tiny part of the system yet are often asked to speak toward the entire system, hence why many will still run their mouth but are painfully ignorant of semi-common knowledge about air quality and current regulations.....bc they're an "authority."

The real challenge to reforestation is "overly concerned" politics, not global warming. In the US we do a piss-poor job of maintaining our forests for fear of upsetting the greenies. If you dont regularly cull the brush, dead, and diseased plants then you have the issues we do today with wildfires and poor plant health leading to high costs for even low quality lumber. My family's owned a sawmill in lower NY for a bit over 70 years and there's been a significant downward shift in forest health over the last few decades. Usually the difference between maintained and "protected" forests is visibly noticeable with the former being large, healthy trees producing good lumber vs the later which is only capable of producing junk firewood.
 
The majority of photosynthesis occurs in the oceans from phytoplankton. Trees are insignificant. So this means we should use more fertilizer if we want to scavenge more carbon dioxide.
 
You know if you put it all to gather, one of the best methods might well be growing apples in an orchard. The fruit would provide income to the caretakers. The wood used in making furniture of quality that people would want to keep for generations. And the leaves, mixed with other compost to keep the soil healthy.

I'm sure there are other examples, but the issue is managed, and income, as well as useful storage of carbon.
 
"If you dont regularly cull the brush, dead, and diseased plants then you have the issues we do today with wildfires and poor plant health leading to high costs for even low quality lumber. "

One might want to recall that many of the trees, particularly in the Southwest and West, actually require fire to properly germinate. Moreover, no one wants to spend the money required to achieve the delicate balance needed for acceptable levels of brush fires that don't kill the trees. What has mostly complicated things now is that we're constantly building into the forests with homes that aren't completely fireproof.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
Much as I like trees they are a con when it comes to carbon capture. They live for a few hundred years at most (and as a commercial venture more like 50) at which point all the CO2 they have sequestred is temporarily stored as wood or paper, or released immediately back into the atmosphere as it decomposes.

Do you have a source on how much carbon is re-released during decomposition? I'm not sure I believe your 100% claim.

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East -
 
You are right, some carbon is retained as organics in the soil, or indeed in the bodies of various organisms that feed on the rotting tree. Of course most wood I'm involved with goes up the chimney!

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Why is carbon capture so important? And why is slowing the carbon cycle not the same thing?

Normal cycle, tree captures from the air. The tree lives so long, then dies. Dead trees release carbon into the air.
If you slow it down, like extending the time it takes to decay (as in the making of coal) such as building homes, or furniture of quality.

Another note is the people who are bringing up sunken trees from rivers, and finding the wood is in very good shape, as in very little decay.
 
Does anyone know what the benefit would be if we could extinguish coal mine and coal seam fires?
I understand that just one can be large enough to emit as much greenhouse gases as all the cars in the US.
It seems that a concerted effort by the international community could put a significant dent in greenhouse gas.


Thanks,
Mark
 
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