If I understand correctly, the proposal is to maintain or renew existing permafrost or ice plugs and covers
The existence of a prior cap indicates clearly that the seal is viable. It's not necessary to contain a pressure, as the clathrate pressure balances that of sea water. The challenge is to prevent warm taliks penetrating the deposit and causing it to dissociate This method isn't leveraged and is likely only suited to a few application sites as a proportion of the whole. The inverse technique of heating to dissociate and mine the clathrate is likely viable, where export or processing of methane is viable commercially A On 12 May 2011 11:41, "Stephen Salter" <[email protected]> wrote: > John > > Thank you for your flattering if inaccurate opinion. > > Before you can assess the feasibility of any sealing idea you need to > know what the source pressure will do as the flow rate is reduced and > the shear strength of the walls of the passage you are trying to block. > I have a nasty feeling that some geological source pressures will be > high and the shear strength of some passages rather low. Can anyone > give me a range of numbers? > > I hope that people proposing the use of large amounts of liquid nitrogen > for geo-engineering applications will calculate the amount of heat > released in the plant that produces it and by the vehicles that deliver it. > > Stephen > > Emeritus Professor of Engineering Design > Institute for Energy Systems > School of Engineering > Mayfield Road > University of Edinburgh EH9 3JL > Scotland > Tel +44 131 650 5704 > Mobile 07795 203 195 > www.see.ed.ac.uk/~shs > > > On 12/05/2011 09:00, John Nissen wrote: >> >> Dear Peter, >> >> Re location of vents of methane from the shallow sea known as the East >> Siberian Arctic Shelf (ESAS), the forwarded message below is from >> Michael Hayes on the geoengineering list. >> >> I'm just keeping you in the loop! There are lots of emails flying >> around about the methane! >> >> I'm also copying this to Stephen Salter, in case he's interested in >> contributing to the debate. I am continually surprised by his breadth >> of interest and knowledge. I will certainly want you both on the >> brainstorming team for the "methane busting" project, if we manage to >> get it funded. We are going to need a lot of original thinking to >> crack the problem. >> >> Cheers, >> >> John >> >> --- >> >> -------- Original Message -------- >> Subject: Re: 1. Using Lair to plug methane vents, 2. Using LN2 to >> fight tundra wildfires, 3. Capturing methane during Lair/LN2 liquefaction >> Date: Mon, 9 May 2011 11:54:02 -0700 >> From: Michael Hayes <[email protected]> >> To: Kevin Layton <[email protected]> >> CC: <[email protected]>, <[email protected]>, >> <[email protected]>, <[email protected]>, >> <[email protected]>, <[email protected]>, >> <[email protected]> >> >> >> >> Here is the Shakhova/ Semiletov study. >> http://earth.usc.edu/ftp/lund/BERING%20SEA%20EXP%20323/Uservol/Articles%20of%20interest/Eurasian%20Basin/Shakova%20and%20Semiletov%202007.pdf >> >> >> If you take a look at Fig. 4, you will see the most likely location of >> vents. The 3 principle towns in the region all have small airstrips >> and Lagashkino has direct access to potential river >> flow hydro-electrical production for use in air compression. It is >> also midway between the 2 principle hot spots. Using Lair as a means >> to cool the principle rivers discharge flow may be a more effective >> use of the limited cryogenics. Also, please keep in mind that this >> entire area has only a few months of practical construction working time. >> >> The upwind/current position of a line between Teksi and the New >> Siberian Islands would be convenient for cloud/water brighting and >> possible tropospheric direct injection particulate SRM. >> >> Capping any vent, regardless of method, will require a means to >> release the build up of pressure. Finding a means for removal or >> refreezing the collected gas needs addressing. Burning should be the >> last option due to NOx production within the polar cell. Using >> cryogenics for fire fighting posses the same issue of NOx production. >> Aerial fire fighting requires an extensive amount of fuel and thus >> fuel storage and CO2 production. And, it would only have a practical >> range of maybe 100 km radius from the few air fields in the area. >> >> >> On Mon, May 9, 2011 at 10:11 AM, Kevin Layton <[email protected] >> <mailto:[email protected]>> wrote: >> >> Mark -- >> >> I like your ideas here. They fit with what Andrew calls >> "leveraging the capabilities of Lair". You bring up an >> interesting question as well -- could some Methane vents be tapped >> in such a manner that essentially they become a source of LNG? >> This is one of those "2 birds with 1 stone" opportunities, since >> the captured methane could be used for local power production. >> >> Also, the aerially deployed LN2 for fire-fighting may be one of >> the few effective ways to combat wild fires in remote regions, >> which would be a great way to demonstrate the effectiveness of >> this technique. >> >> -Kevin >> >> >> ------------------------------------------------------------------------ >> From: [email protected] <mailto:[email protected]> >> To: [email protected] <mailto:[email protected]> >> CC: [email protected] <mailto:[email protected]>; >> [email protected] <mailto:[email protected]>; >> [email protected] <mailto:[email protected]>; >> [email protected] <mailto:[email protected]>; >> [email protected] <mailto:[email protected]>; >> [email protected] <mailto:[email protected]>; >> [email protected] <mailto:[email protected]> >> Subject: 1. Using Lair to plug methane vents, 2. Using LN2 to >> fight tundra wildfires, 3. Capturing methane during Lair/LN2 >> liquefaction >> Date: Mon, 9 May 2011 09:02:34 -0700 >> >> Ref- Andrew's post earlier today: >> "Using liquid air to seal methane vents may well work. Using it >> for general >> cooling of the sea or land surface will not." >> >> *I had posted the following to the google group, but it didn't >> seem to take, so here it is via email:* >> >> John and All- >> >> Andrew makes a great point. If methane release tends to be limited >> to vents or so-called "hotspots", and the number of vents is a >> reasonable amount, the use of Lair or LN2 to freeze and seal these >> vents becomes MUCH more feasible than trying to cool/refreeze >> large permafrost regions. >> >> Are we able to determine the number of these vents using >> satellites, aircraft etc? If so is this information currently >> available? This would be the primary consideration for >> feasibility- if it's something like 10,000 or more vents, at some >> number it just becomes unreasonable. However, on the order of >> 1,000-3,000 vents would seem feasible and on the order of hundreds >> would be very feasible. >> >> Another consideration would be liquefaction capacity- whether >> existing liquefaction plants are close enough to support this >> activity, or if it would make more sense to build new plants >> (maybe 2-4) near existing high-latitude airports (these plants are >> quick/easy to build). Ideally it would be great to power them >> using captured methane (!) or by harnessing the strong/steady >> winds of the tundra. >> >> Secondly, as warming and drying continues in permafrost regions, >> this will create imminent danger of tundra wildfires, which can >> cause enormous CO2 and methane release. Already in July 2009 >> intense fires burned large permafrost regions in Russia, Canada >> and Alaska (see >> http://climatechangehealth.com/arctic/smoke-from-tundra-fires-in-russia-and-alaska >> ). >> >> However, I believe future wildfires could be more-effectively >> controlled using liquid nitrogen (LN2), by releasing a wide stream >> of LN2 on or just upwind of the fire lines via aircraft. The LN2 >> would then expand over 800 times into a cold/heavy gaseous >> nitrogen, and be pushed by the wind to form a "GN2 blanket" >> covering long portions of the fire line. By diluting oxygen levels >> from 21% to below 15%, combustion should be eliminated and the >> cooling provided would help prevent re-ignition. >> >> This method could provide greatly-improved capability for >> extinguishing large wildfires compared to current firefighting >> methods using water and/or fire retardants. If this method was >> shown to work in the tundra, it could create confidence for using >> it at lower latitudes, where wildfires are already becoming more >> intense from severe droughts and record high temperatures. >> >> Thirdly, the liquefaction process for creating Lair or LN2 might >> also capture a significant amount of methane in the process. Since >> liquid methane boils at a warmer temperature than Lair or LN2, >> cooling methane-rich air would form liquid methane first, allowing >> it to be distilled from the cold air and stored in >> highly-insulated dewars. Note: methane boils at -161 °C (-258 °F), >> while air and LN2 boil at -196 °C (-320 °F). >> >> To summarize, by creating the capability for delivering Lair/LN2 >> at high latitudes, this might provide a three-fold benefit of >> mitigating methane release, controlling large wildfires, and >> distilling liquid methane out of ambient air. >> >> John please help with the number of methane vents. >> >> I would appreciate any and all comments!! >> >> Thank you- >> >> Mark >> >> >> >> >> -- >> /Michael Hayes/ >> /360-708-4976/ >> http://www.wix.com/voglerlake/vogler-lake-web-site >> -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
