CO2 Storage In Deep Saline Formations Can't Work

So, do you have a question, are making a comment, or have a solution to sell?

Trying to sell his companies solution. The patent doc lists him as one on the inventors.

Wilmot -- Very interesting commentary you provide here. It's way over my head with respect to any critical commentary. But interesting.

I wonder how widely your skepticism over the practicality of CO2 sequestration is supported.

One statement you made is that "you can't just dump the brine". I'd like to know some of the reasons why. Being close to the subject you can probably answer a question for me. Seriously....... What volume (say cubic meters) of solid salt would have to be extracted along with the water, of course, to support the operation of a 1GW coal fired power plant using 100% sequestration of it's CO2 output? It may be practical to use the same railroads that bring the coal to the powerplant to return it to large western playas starting with the Bonneville Salt Flats where it would be available for extraction of minerals like potash. There are many alkali playas in Western USA that would essentially sequester the salt for tens of thousands of years.

This also begs the question of why the salt brine could not be diluted and added to the oceans in a manner that would not upset the resident marine life. Do we have any decent data on the actual chemical makeup of these brines?

Ed Weldon

Ed, reverse osmosis for desalination has been limited by the availability of a disposal site for the reject brine. For example, the Yuma Desalting Plant in Arizona. The EPA classifies RO reject brine as "industrial waste" so presumably the same classification would apply to the brine pumped out of the storage reservoir. Dumping it in the ocean would produce a saline plume, like a local Dead Sea. If the RO reject brine problem is so difficult, it is hard to imagine the difficulty of handling a much, much larger volume of even saltier water. Earlier this year, Ehlig-Economides, et al. disputed the capacity calculations for sequestration in an important article published in the Journal of Petroleum Science and Engineering.

Doesn't the CO2 dissolve in the water?

Yes CO2 dissolves in water to a point of saturation (much lower than the volume in storage as compressed gas). Dissolved CO2 acidifies the water and dissolves the minerals. When saturated with calcium and magnesum you get dolomitic or lime deposition occurring. However, you must consider the dissolution of minerals a possible source of subsidence. Some minerals such as clays and quart won't dissolve in the carbonic acid that is formed.

Electrolytic dissociation of CO2 looks to be the only thing left to try. The bond dissociation energy for getting to CO is 5.5 eV, about the same as water electrolysis. Simultaneous cracking of water and CO2 yields syngas (CO + H2) and oxygen. The oxygen can be recycled into combustion or gasification, and the syngas can go through the Fischer-Tropsch synthesis to become vehicle fuel. Sandia National Lab is using solar energy for the simultaneous electrolysis of water and CO2 . See also this patent application for a hybrid power system. The energy for cracking should come from wind and solar because fossil fuels create more CO2 than they crack. So instead of trying to connect remote and intermittent wind and solar sites to the grid by transmission lines, we can pipeline CO2 to these sites for cracking. Radial counterflow shear electrolysis is what looks good to me. The GAO shares our pessimism about the prospects of sequestration, but for them the deal-breaker is the public acceptance of a lethal gas dump under where they live.

Please go back and review your first year physics and chemistry. The energy you need to take apart the C and the O2 is the same energy you got when you put them together in the coal burning process. And this doesn't count process inefficiencies (2nd law of thermodynamics for starters) which likely greatly outweigh the energy value of hydrogen components of the coal such as would come out in a coking process.

If you are going to make a case for or against impracticality of CO2 sequestration please leave the junk science and ignorance of basic thermodynamics on the floor where it belongs.

Ed Weldon

Ed, of course you are right about the cracking energy merely replacing the energy produced by combustion. I'm not claiming that there is free energy in CO2. That's why wind and solar are the preferred power sources for the cracking. The energy they supply has no fuel cost, and produces no CO2. I don't see a problem with process inefficiencies because even if a lot of renewable energy gets wasted converting CO2 to fuel, it cost nothing to begin with. Cracking is a job that renewables can do whenever and wherever their energy is available, so, effectively, CO2 becomes means for energy storage for wind and solar. Otherwise, without means for storage their energy must go to waste, and there can be no realistic plan for wide deployment despite quotas because wind and solar are intermittent and remote. Another power source for cracking is the surplus power available at night due to 24-7 baseload power generation. Oxygen (for oxygen-blown gasification or oxyfuel combustion) is another valuable byproduct of cracking, so you can avoid the cost and energy penalty (~30%) of the conventional cryogenic air separation unit. Cracking CO2 is a way to get wind and solar unstuck. They are never going to be suitable for baseload generation, and they should not try.

Storage at what cost? This is simplistic, idealistic green talk - nothing more.

No fuel cost for solar or wind is correct but capital cost for solar or wind is definitely there and it is very-very high as of yet.

You are talking about an intermittent process which usually complicates hell out of a process.

We need a few advances in process technology to bring storage of whatever kind to life. When it happens it will be great but trying to dance around existing technology while shaking a rattle won't do the job. Pumped storage is used but has very limited potential.

Voodoo economics seem to be at play here.

I share your distaste for simplistic, idealistic green talk. And I agree with your point about the capital cost for solar and wind -- especially if backup generation from gas is necessary to compensate for the intermittency. In a reply to an earlier post of yours, I gave some links to further information, in case you are interested before forming a final judgment on me or the merits of the hybrid power concept.

Went to the links and made some comments.

Love to see something like this work but I think it is still many years out. A new process is not an easy thing to scale up and make commercial.

I have been involved with that type of thing - started in Portland, OR matter of fact back in 1970. The first Midrex plant was located by Oregon Steel in the North Portland industrial park. That process was a long hard row for Midland Ross Corp and they ended up dumping it just before it started to make money.

Don't forget O&M cost and the carbon footprint in that.

"The more practicle solution seems to find a way to break the bond between C and O2 in the molecule and release the O2 back to the atmoshere and reusing the carbon in agriculture and industry."

The process is called photosynthesis, and it occurs in green plants as they make sugar as a solar energy storage product by using CO2 and water while restoring the Oxygen to the atmosphere. The polysaccharides thus formed make the basis for our food and renewable liquid fuel supply.

The real solution can be found by googling "Gaviotas" which is a village in Colombia where tropical rain forest cover has been successfully restored. Too bad nothing will happen until government can figure out a way to tax it or the "professional" research community can turn it into a major 10 year "research" budget.

Billions to study CO2 sequestration? Bouncing around some big numbers.

The money being spent is maybe 95% or more toward CO2 separation?

It seems you say that breaking the CO2 bond and the H2O bond require similar amounts of energy? I have yet to read of anything happening outside of the lab that even starts to make sense for electrolysis.

At present this is no home for solar or wind power usage - to much power required for that. That only makes those two sources more impractical than they already are. Without massive impractical subsidies both would be limited to the occasional of grid application.

russ123, this article might answer your questions about the money. As for CO2-to-fuel projects, see this Sandia project. For more information on the energy requirements for the application of wind and solar to the cracking task, see this patent application.

I have been following CO2 separation closely for the past 15 years due to potential process applications associated with the process I worked with.

This article and big bucks - They are talking about carbon capture - not carbon sequestration really despite what some fool author may have written. The problem to date is to remove CO2 from the gas stream economically. When the CO2 can be separated economically then storage becomes important.

Sandia project - The process I worked with used dry reforming (not steam reforming) to convert CO2+H2+CH4 to CO+H2 with small amounts of CO2+CH4 in the product gas stream so I am somewhat familar with reforming though I am not an expert.

What Sandia is talking about is in the future and I really doubt their 2013 date to start building commercial plants. They have yet to show it work on a commercial basis.

Lockheed Martin has it's hand in the government pocket so will say anything to keep the gov happy. All the government agencies are busy trying to make points with Obama by agreeing to anything green he or his people dream up.

Patent applications - meaningful to the party that filed it but to anyone else? Thanks for the link though as it shows where you are coming from as you are listed as an inventor. You might have pointed your vested interest out up front rather than attack something that can be done.

CO2 sequestration is quite useful for enhanced oil recovery in some oil fields - The Great Plains Gasification Project has done it for years.

Post-combustion CO2 capture by amine sorbents is another doomed idea for managing CO2 emissions on a large scale. Estimates of the cost of chemical capture go as high as $333/ton, but nobody knows for sure. I have a pending application on an alternative method which does not require mixing in chemicals to a hot and dirty gaseous emission stream. It's centrifugal gas separation in radial counterflow between counter-rotating coaxial centrifugal impellers with feed at their axis of rotation. The N2 and steam go radially in to axial extraction (assisted by a steam ejector) through an area-preserving fractal vortex network in the shear layer between the impellers, and the CO2 (along with the fly ash, Hg, NOx, and SOx) collect in a shrouding tank. At thermal equilibrium, the higher molecular weight of the CO2 means that it has higher momentum than molecules of N2 or H2O, and therefore it will be excluded from the vortex cores and will collect in boundary layers against the impellers. If you can strip out the N2 and steam that constitute 80% of the volume of flue gas, you've essentially done carbon capture. At least you've reduced the volume of the waste stream you need to process downstream. I am trying to have a civil discussion here, and not to "attack something that can be done." CO2 sequestration in DEEP SALINE FORMATIONS (not EOR projects in depleted reservoirs) cannot be done because the pores are full of brine.

First - not all "reservoirs" are filled. There are large areas with porous dry rocks, Crisfield Maryland and the Barre Vermont being just two of them. USGS went on a quest for these formations in the 1980's hoping to find some hot enough to make steam. Mostly, they were only at standard geological temperature gradients. So if they say we have reservoirs available, we probably do. I have first hand wire line logging experience on the two mentioned. They are there, and they are totally dry.

Secondly - if a formation is being considered as a storage reservoir, there is going to be an impermeable cap rock over top, or the formation would not have been considered in the first place. Fracturing is going to occur - it will be done before the injection of the CO2. Nothing is coming back to the surface, at least not soon, as these formations are on the order of 10,000 feet deep.

Phys, dry reservoirs and depleted oil and gas fields are not within the ambit of this discussion, which concerns the plan for CO2 storage in deep saline formations. Why there? Because dry reservoirs and depleted oil and gas fields are not enough for the huge volume that would have to be stored underground. The link to the Burruss testimony is inoperative, so here is an extended quote to clarify this important point:

"Another aspect of CO2 storage in saline formations that impacts our evaluation of risk

factors is the scale of storage projects and the volumes of CO2 that must be injected into

storage formations as geological sequestration is fully deployed. The CO2 emitted by a

single, 1000 megawatt coal-fired electrical generating station is roughly 8 million tons

per year. If that CO2 is captured and injected into the subsurface, it will displace about

84 million barrels of formation water. Over the lifetime of a single full-scale storage

project of this size, for example, for 50 years, the total volume of CO2 injected into the

subsurface, and the volume of water displaced, will be equivalent in volume to about 4.1

billion barrels of oil. This volume corresponds to a 'giant' oil field, according to

terminology used in describing oil field sizes. There are physical traps of this size in the

United States, but the number is limited. The geospatial mismatch between size of

storage needed for sequestration projects and the location of large sources of CO2 has

been addressed in a USGS report published in 2006 (Brennan and Burruss, 2006). If

geologic sequestration is deployed to the extent that the Nation is storing about 500

million tons of CO2 per year, equivalent to emissions from 50 to 60 coal-fired power

plants of 1000 megawatt size, then we must recognize that the storage process will

displace about 0.6 km3 or 172 billion gallons of formation water each year. Such large

movements of saline formation water have the potential to disturb regional ground-water

flow systems, possibly displacing saline formation water laterally or vertically to nearsurface

environments where it could contaminate shallower drinking water supplies or

impact ecosystems."

http://energy.er.usgs.gov/images/co2_sequestration/burruss_testimony_2008.pdf pp. 11-12.

If there were a problem with CO2 I could see that we would want to try to elevate it. However, the so-called problem with CO2 is only political, it is not real. CO2 is good for plant life.

So, leave the CO2 to the plants. Let it be where it belongs on the earth surface promoting plant and tree growth and ultimately food production.

Isn't ignorance wonderful!! Like losing yourself in a good movie and a pleasant buzz.

Ed Weldon

Ed, I did not expect any other answer with all the brain washing going on.

Believing makes you happy, thats so wonderful and everybody feels good about it.

Actually, higher levels of CO2 can favor certain species of plants much more than others, as some plants pathways have evolved to take more efficient advantage of the lower CO2 levels of the modern environment (within the last 30 million years) and this comprises much of their competitive edge. A change in CO2 level could negate this edge and likely make much older species much more competitive to overtake the more modern evolved species many of which we depend on.