neil, no problems. im just trying to keep the scope of the present research in mind, cause what happens in many cases, we get a project that develops a neat tangent which we blow resources investigating , then we are what?, without any more budget.
Also, they are trying to sequester the gas so that they can push it in , at an expected sustainable rate, without it "leaking out' thats why the ocean wouldnt work, besides, the CO2 would dissociate and cause carbonic over the amount thats in equilibrium now. I think that theyve carefully considered where the research will start, and its only going to be studied where they can easily collect and compress CO2.
, a story
I remember , about 12 years ago. The mining engineering Dept and the Hydrology dept of penn State proposed creating"artificila aquifers" . In Pa we have lots of old open pit mines that have been all dug out. many areas of the state look like the moon.
Penn State proposed creating these artificila aquifers by filling up these abandoned coal mines with suitable sized gravels and rock so that they could become a porous media to store rainfall and clean recharge water. However there was one obvious question that stymied this proposal. Where are we gonna get all the rocks to fill up the mine. Well we couyld dig another hole and scoop up the rocks there, thus leaving a new hole in a different place,
thats why Im not really excited about this proposal for sequestering CO2, theres probably 1 little thing that may make it totally unreasonable. I think that the collection and separation of CO2 out of a flue gas could be a lot of it.
your idea for disposal of nuke wastes into subduction zones was actually looked at seriously by SAIC and the staffs at Sandia labs and the Nevada Test Site , and the guys at WIPP in Carlsbad. They had all kinds of ideas to conduct research but realized that, without actually using nuclear wastes in an at risk test, wed never really know whether it would work. So it was "put aside" until technology was available that allowed us to track stuff moving in a subduction zone.
Roger, hey sorry i was confusing but, the thing that pisses me off about me, is that I write in a stream of consciousness basis and I rarely look to use spell check, so my thoughts may not be coherent. im sorry, to have misrepresented what they were gonna do in this research program. They want to test a susatinable pumping into a reservoir that could accept and hold CO2 just by using the "thermos bottle" of the earth
The only experience I have with re-injecting streams back into the ground is "produced water" from crude oil processing. Virtually all crude oil out of the ground has water in it - sometimes only a few percent, and sometimes much higher. Before crude oil can be loaded onto tankers for export it must be desanded, degassed, dehydrated and desalted.
To dehydrate and desalt the crude oil, it is flowed through three "desalter vessels" in series. An electrostatic charge is maintained at the top of each vessel that aids small water droplets to combine into larger drops, and then fall to the bottom. Water is then drawn off of the vessels. Fresh water is injected to help wash out the salt. Crude oil from the well typically has 1500 pounds of salt per 1000 barrels. The specification for sales is 7 pounds per 1000 barrels.
The water separated from the crude oil is nasty stuff. It's saturated with hydrogen sulfide gas, and it's salt content is around 150,000+ ppm (seawater is 45,000 ppm. The strongest mineral water I've ever had was 800.) The onshore Plant I used to work at made around 35,000 barrels a day of this "produced water". We disposed of it by pumping it at about 1500 psi into a formation around 8,000 feet down.
Sorry, but I've had no experience with re-injecting gas streams.
Hi Jim: Perhaps everyone except me has been typing about pumping liquid carbon dioxide. I believe the pressure is reasonable at 4 degrees c to keep it liquid. I had not considered that dry rock is a good thermal insulation until Farmerman mentioned "thermos bottle" I suppose a large body of liquid carbon dioxide would only warm about 1 degree c per month even if rock was 100 degrees c warmer in all directions a 100 meters away.
So is this 4 degrees c liquid carbon dioxide that is displacing methane in low grade coal? Will this work 100 meters below the surface, if the liquid carbon dioxide is colder than 4 degrees c, where the rock pressure is only 9? atmospheres, or am I thoroughly confused?
Is the air venting to the surface of a working mine typically 1% methane? Neil
methane is a reaction offgas as well as a trapped gas. "town gas" was a manufactured gas from coal mines that was popularly used in the 1800s to light lamps. The pressure and temperature gradients are such that its possible to collect methane and hydrogen without pumping for years.
the fractures in a deep mine (coal) are such that CO@ as gas or liquid will expand and prefer a gaseous state , which, according to the researchproposal data Ive seen, will(they hope) cause a "wet" methylated hydride to form as a reaction with the coal "bony layers", which are more like charcoal or lignite than harder coals. The first test mine area will take a few years to find so that all the variables can be controlled at the site.
One of the reasons theyve not jumped onto old oil or gas wells is , as Jim said, "Sour gases" can be a deadly problem and the resaerchers dont want to be responsible for forcing up dangerous amounts of H2S
like they have had in a few Alberta fields.
Seems the introduction of H2S would create a area of low pH. How does this increased acidity influence the proposal?
as I understand , they are trying not to use any sour gas wells or wells with significant H2s. i think the safety issue is more significant to them at this point. Since this thread started, Ive only heard one thing about the project and that was the first sequestering experiments are going to be in a small , well defined coal ime area. Poland has many coal mines that are deepThey dont want too many variables to screw with.