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Post by rgolubev on Jul 21, 2015 11:49:08 GMT 9.5
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Post by Roger Clifton on Jul 26, 2015 18:56:39 GMT 9.5
Roman – when a coal company says they are doing something good for the greenhouse, you can be confident that it is just greenwash. EOR ain't CCS. Enhancing oil recovery with a CO2 flood does not leave the CO2 underground. The gas is injected into the reservoir, where it dissolves mainly in the oil. There it breaks down the hydrogen bonds between the hydrocarbon molecules, reducing the viscosity of the oil. Because it also increases its volume, the oil emerges from its nooks and crannies in the sponge and pushes the water away from the drawdown point. Once the CO2 has returned to the surface in the oil, it still serves a purpose in maintaining the low viscosity of the oil, so it may not be released back into the atmosphere immediately. But sooner or later it is released from its phoney sequestration, and whether the delay has been hours or days, it is nothing compared to the thousands of years required to protect the greenhouse. You have been misled. Don't believe a word of it.
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Post by rgolubev on Jul 27, 2015 18:45:10 GMT 9.5
Hi Roger,
I don't think what stated in the article re using CO2 for EOR is misleading. It does seem to make sense economically to build these CCS next to this kind of consumers. Otherwise it's just not economically viable. As I understood, CO2 then can be recovered from the extracted oil.
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Post by Roger Clifton on Jul 28, 2015 13:45:01 GMT 9.5
When someone says that something is okay "with CCS", carbon capture and sequestration, we should always cry foul because the "sequestration" is always fiction. To be effective, sequestration would have to keep vast quantities of CO2 gas out of the environment for thousands of years, which is just plain not possible. CCS never was a viable solution, it has been greenwash from the start.
I see a period ahead of us when our leaders will evade zeroising carbon emissions by repeatedly substituting coal with nat gas, while using words to the effect, "there will be no new gas-fired power stations - except those that undertake to operate with CCS". We must call them out every time, or every energy initiative will cheat us back to emissions/business as usual.
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Post by David B. Benson on Jul 29, 2015 11:08:09 GMT 9.5
One way to sequester is to react, exothermically mind you, with ultramafic rock. Even just mafic rock will do. Then the CO2 is permanently bound.
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Post by Roger Clifton on Jul 30, 2015 17:19:42 GMT 9.5
.... And felsic rocks too. The vast amount of CO2 to be removed from the atmosphere/hydrosphere requires a tenfold vaster mass of rock to be weathered. If the process were to be accelerated, the disposal of the resulting toxic slurry would present a similarly vast problem.
Long after mankind has stopped releasing fossil carbon, it is the weathering of rock that will eventually restore the concentration of CO2 to equilibrium with its sinks and sources. As far as I know, it is the only forcing which is enduring, restorative and increases with both CO2 concentration and environmental temperature.
However the process of repair is much slower than the rate of our damage. If it is to take a million years, it would seem that our species will have to adapt to a high-CO2 world for the rest of our presence in the fossil record.
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Post by Greg Simpson on Aug 2, 2015 5:49:17 GMT 9.5
We can speed up the natural weathering by a huge amount.
There are not many places where I think it would be safe to have the equivalent of square kilometers of loose asbestos covering the land, but there are some. It's not desirable, but it may beat the alternatives.
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Post by David B. Benson on Aug 6, 2015 10:09:05 GMT 9.5
Roger Clifton --- Mafic rock, basalt around here, weathers to clay. Ultramafic rock is much the same. There is enough ultramafic rock surficially exposed in Papua New Guinea alone to remove all the excess CO2, although the Paupuans might object. Just north of New Guinea there are exposures on the ocean floor and nobody would object to using those. If that isn't enough, there is also an exposure in northern New Calendonia.
And if more is required there are the vast basalt fields of the Pacific Northwest, the Deccan Traps and the Siberian Traps.
Greg Simpson --- There is nothing toxic about these weathering products; it is just clay. But yes, there are several papers on means to inexpensively speed up in situ weathering and at least one on an ex situ method.
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Post by Roger Clifton on Aug 6, 2015 15:03:38 GMT 9.5
DBB - Don't believe the spin.
Sure, on a geological timescale, the vast (mafic) basalts spreading from the midocean ridges absorb CO2 during serpentinisation, releasing a certain amount of methane in the process and a harmless trickle of minor elements that were associated with the sulphides being released. Minerals formed include talc and crocidolite. After 100 million years or so of drift, the serpentinite undergoes a messy subduction process, during which some CO2, methane and sulphides return to the seafloor through smokers and mud volcanoes.
On land, CO2 in the groundwater gradually attacks all rocks including felsic rocks, where the aluminosilicates are separated into cations and clays. Converted into bicarbonate ions, the CO2 travels, some becomes fixed in calcrete and shell beds and the rest re-enters the atmo/hydrosphere. Again, the minority elements leak out only slowly.
Accelerating it on a human time scale is problematic. Considering that there is currently 1.5 kg excess CO2 over every square metre of the earth's surface, with a similar mass in the oceans, its removal would require conversion of rock on an unprecedented scale. Depending how you read equation 2B in (ref), you would need to process enough basalt to contain olivine in proportion 17.5 times the mass of CO2 to be absorbed. That would result in more than 2×1.5×17.5 = 52.5 kg/m2 of grey sludge for every conceivable square metre of the earth's cities, farmlands, rangelands, forests, oceans and ice. Totalling more than 27 Eg, ie 27,000 Gt or 10,000 km3...
Considering the industrial speed that the mixture of elements in rock are to be released, the liquor would indeed be toxic. It would also be alkaline at pH ~10, depending on the pressure of CO2 applied.
Just by voicing the possibility that such a project is feasible, we would give an excuse to the world's carbon emitters to continue business as usual. As a consequence, we would have to commit to continue the process, year on year, to remove the ongoing 30 g/m² per annum of CO2 being added to the atmosphere and a similar 30 g/m²/a into the ocean. Perhaps we should consider its ongoing removal as a dustfall of 2×.030×17.5 ~ 1 kg/m²/a, endlessly adding to the unmitigated combustion smog.
... Let's not give credence to the idea.
PS: Here is evidence of groundwater bicarbonate, on its way to form desert calcrete.
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Post by Greg Simpson on Aug 9, 2015 9:04:38 GMT 9.5
Greg Simpson --- There is nothing toxic about these weathering products; it is just clay. But yes, there are several papers on means to inexpensively speed up in situ weathering and at least one on an ex situ method. The preferred rock for sequestration seems to be serpentine, and chrysotile (asbestos) is often present. I wouldn't want it done near where I live.
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Post by Greg Simpson on Aug 9, 2015 9:56:39 GMT 9.5
Just by voicing the possibility that such a project is feasible, we would give an excuse to the world's carbon emitters to continue business as usual. As a consequence, we would have to commit to continue the process, year on year, to remove the ongoing 30 g/m² per annum of CO2 being added to the atmosphere and a similar 30 g/m²/a into the ocean. Perhaps we should consider its ongoing removal as a dustfall of 2×.030×17.5 ~ 1 kg/m²/a, endlessly adding to the unmitigated combustion smog. ... Let's not give credence to the idea. It comes down to the cost. I've seen estimates of $10/ton of CO 2 and demonstrations of $5000/ton. Once we really know the cost it tells us what we should charge for it. If it's affordable we can store the effluent from mobile sources of CO 2, if it isn't we can ban them.
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Post by Roger Clifton on Aug 9, 2015 19:10:52 GMT 9.5
Alright, if we have to, but let's also charge them to dispose of all that grey sludge -- somewhere.
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Post by David B. Benson on Aug 12, 2015 9:13:47 GMT 9.5
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Post by David B. Benson on Aug 12, 2015 10:17:21 GMT 9.5
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Post by Roger Clifton on Aug 12, 2015 13:14:35 GMT 9.5
DBB -
Crushing blue basalt into a mud with water and CO2 retains all of its iron, magnesium, sulphides and heavy metals etc, yuk. Only the passage of geological time can leach them all away, leaving white clay. That's on land, whereas under sea basalt takes up water and becomes serpentinite. If crushed for carbonation, more mass of serpentinite is needed and it gives nastier mud than basalt.
But none of the references you quoted speak of the elephant in the room: Where are we going to dump all this waste?
Dumping waste gas into the greenhouse is wrong, has been known to be wrong for decades. Making it bigger and nastier and dumping it somewhere else would also be wrong and its consequences potentially worse.
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Post by David B. Benson on Aug 14, 2015 11:42:09 GMT 9.5
Basalt around here isn't blue and the clay isn't white. Both are brownish,I suppose from iron oxides. In situ methods do not involve crushing.
I have already suggested some sites which have great thickness.
Obviously we have to stop using carbon from the ground but we need methods to remove the excess carbon dioxide. Possibly accelerated weathering can be one of the removal methods.
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Post by David B. Benson on Aug 21, 2015 11:41:39 GMT 9.5
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Post by Roger Clifton on Sept 24, 2015 20:54:09 GMT 9.5
Weathering of basalts does contribute significantly to the stabilisation of greenhouse gas concentrations in the long-term. However on a shorter timescale, flood basalts have also been major sources of instability. Most of the major extinctions ( ref) have each been associated with a great outflow of basalt ( ref). In these rare events, millions of square kilometres of fresh basalt are exposed to the air. At first glance it would seem that the CO2 emissions associated with mafic outflows had caused faster climate changes than the terminating fossils could adapt to. However the measured rate of CO2 emissions from modern basalt flows ( ref) is too low to support that explanation. On the other hand, the methane emitted during early, rapid weathering ( reaction 2a) may have been sufficient to disrupt the climate. This process also suggests an explanation of why the atmosphere recovers after each great extinction. Once soil begins to cover the basalt, the continuing methane emission becomes food for the microbiota, so that bacteria convert ( ref) the methane into bicarbonate instead. Absorption of CO2 during weathering then dominates as the basalt becomes a net absorber of greenhouse gases, tending to restabilise the disrupted climate.
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Post by David B. Benson on Apr 8, 2019 13:04:05 GMT 9.5
Blamed for Climate Change, Oil Companies Invest in Carbon Removal Clifford Krauss 2019 Apr 07 The New York Times
This Rube Goldberg-esque air capture appears to be a David Keith invention. Not even quite a prototype yet, it does hold promise for supplying carbon dioxide from the atmosphere. There are cost estimates.
I was amused by the claim of one of these units being equivalent to 30 million trees. But since more than 3 trillion more trees are required, well, you do the arithmetic.
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Post by Roger Clifton on Apr 9, 2019 2:16:05 GMT 9.5
Carbon Engineering has constructed a "direct air carbon" dioxide extraction plant and promises to make synthetic fuel out of it. While both processes have established precedents, both of them need R&D to reduce their costs below the current cost to the gas station. For example, these guys are precipitating calcium carbonate (exothermic) and subsequently roasting it (endothermic) above 950° C. That energetic detour is both expensive and unnecessary. Sodium carbonate solution would also trap CO2 but the solution only needs to be near-boiled to release it. Ammonium carbonate would be more efficient, but releases fugitive ammonia, a greenhouse gas. Modern processes have long since moved on, with membrane processes at least on laboratory scale: bravenewclimate.proboards.com/post/2331/threadCritics warn that the exercise is only getting token funding so far, and may only get as far as being used as greenwash by the oil companies' spin doctors. Is it for real? References to underground sequestration (impractical to the point of fraud) indicate insincerity. However, oil companies are composed of people who have or will have grandchildren. They may be more flexible to change than tradition implies. Further, if anyone would know how to make and distribute synthetic fuel around the globe, it would be know-how within the fuel companies themselves.
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Post by David B. Benson on Apr 9, 2019 12:46:21 GMT 9.5
Field Validation of Supercritical CO2 Reactivity with Basalts B. Peter McGrail et al. Environmental Science & Technology Letters 2016 Nov 18
Inserted with a little water at up to 90 bar the CO2 had all formed carbonates before the 2 year later test.
I didn't find any cost estimates.
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Post by Roger Clifton on Apr 10, 2019 11:40:41 GMT 9.5
...the CO2 had all formed carbonates Well, not all of the carbon dioxide, only some of it had been converted to a mineral carbonate. The rest of the CO2 would have escaped to the surface, entered the groundwater or entered into more complex reactions with the country rock. Because basalts is alkaline, we can expect that CO2 will form carbonates with it. Because basalts is a reducing material, we can expect that CO2 will also form methane. Methane that will leak into the atmosphere and counteract in some part the removal of CO2. The thousands of tons of chemically unstable, toxic sludge that remains after their injection of one thousand tons of supercritical, acidic CO2 represents a preventable waste form, an unnecessary damage to the environment. Did they have EPA approval to perform this experiment? What did this exercise prove? It was already known that there is far too much CO2 for it to be buried underground. The man in the street might be fooled when told, its alright, we are burying it all underground. For there never was going to be "all of it". In fact, God forbid that any significant portion of the CO2 gets buried underground, because it would create one God almighty mess, too big to be cleaned up. Who gained? One clue is that all of the authors belong to the Pacific North-west National Laboratories, which is managed by Batelle, who among other things, perform "services to industry". One can only guess which industry is being served.
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Post by David B. Benson on Apr 10, 2019 13:00:24 GMT 9.5
Batelle Northwest is a not-for-profit which manages PNNL for the DoE Division of Science. Somehow PNNL managers and the DoE agree on the science to be funded from congressional appropriations.
Avoiding the paywall around the paper, a summary is found in
Geologic Capture andrbon: Sequestration of Carbon: Proceedings of a Workshop --- In Brief The National Academies Press 2018
Summarizing, nothing monitored for escaped. Indeed, given the physical structure of the basalt columns escape is improbable. Most of, but it seems not quite all, the carbon dioxide formed ankesite inclusions; not a mess in the slightest. A picture of a core sample is included.
Recall that the test proceeded well underground. Surficial weathering this is not.
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Post by Roger Clifton on Apr 11, 2019 1:31:11 GMT 9.5
Here is a link to the figure DBB mentioned, and a summary of the paper. I couldn't get to the paper itself. www.nap.edu/read/25210/chapter/1#6The figure identifies the new carbonate but also chalcedony. Chalcedony is microcrystalline silica, after all the cations have been dissolved, implying an acidic solution. In basalt the cations are mainly magnesium and iron (in the reduced state), with other alkaline earths, alkalis and (in this acid) aluminium. Anions include sulphide, chloride, fluorine and vanadium. The summary does not describe where they end up. I call it a mess, considering that 1000 tons of CO2 had been injected. Not all the CO2 had reacted. The summary describes a remaining compressibility of the ground, implying the presence of gaseous CO2 and a larger quantity in solution. The exercise remains futile in that it cannot represent a destination for the far-too-great quantity of CO2 in the atmosphere. Instead it allows the fossil industry the pretense that it is doing something useful about CO2. That we must not indulge. Fossil use must be completely eradicated, no excuses.
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Post by David B. Benson on Apr 11, 2019 16:04:17 GMT 9.5
Roger Clifton, thank you for the link to the workshop writeup.
The chalcedony is a mineral constituent of the original basalt at Wallowa. The geochemistry of all the Columbia Flood Basalts is described in series of papers by Peter Hooper with various coauthors, mostly also associated with Washington State University, from the 1970s. This particular formation is surely further characterized by the group at PNNL, available by request from the communicating author. In any case, it has nothing to do with the experiment.
As the formation of carbonates in mafic rock is exothermic the result is chemically stable. The concentration is so low that the physical properties of the host basalt are hardly affected; it is geologically stable in the geologically stable zone of the flood basalts, upon which I reside.
In brief, feasibility has been demonstrated. The desirability, indeed the cost, are properly the subject of a different thread, in the Climate Change section I should think.
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Post by David B. Benson on Nov 6, 2019 15:24:05 GMT 9.5
Turning carbon dioxide into rock --- forever Valeria Perasso 2018 May 18 BBC News www.bbc.com/news/world-43789527Using more water appears to avoid using supercritical carbon dioxide.
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Post by David B. Benson on Nov 6, 2019 17:36:02 GMT 9.5
CO2 Mineral Sequestration in Naturally Porous Basalt Wei Xiong et al. 2018 Feb 27 Environ. Sci. Technol. 2018, 5 ,3 pubs.acs.org/doi/10.1021/acs.estlett.8b00047#The post-analysis of the PNNL CO2 injection. It appears that the Grand Ronde basalts can trap about 47 kg of CO2 per cubic meter.
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Post by David B. Benson on Nov 7, 2019 17:04:27 GMT 9.5
So how much basalt is required?
Each cubic kilometer is to sequester over 45 megatonnes of CO2, from the PNNL study. So 22 km^3 holds a gigatonne, GtCO2. But, assuming ocean outgassing, 16 GtCO2 per atmospheric ppm; that's 356 km^3 by rounding up. For each and every excess ppm of carbon dioxide in the atmosphere.
We want to remove, say, 135 ppm. But here on the Columbia Plateau alone there is enough basalt for over 800 ppm.
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Post by David B. Benson on Nov 9, 2019 8:39:14 GMT 9.5
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Post by David B. Benson on Nov 9, 2019 9:07:30 GMT 9.5
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