Could someone please explain why you would want to throw fuel into the sea?
Surely it's better to: a) Burn it, then use CCS b) Pyrolise it to recover energy and to reduce mass/bulk and then throw the char in the sea. Just to question the 'safety factor' of terra preta as opposed to ocean burial: As I understand it there's actually a net benefit to biochar, as it helps 'bulk' the soil and cause it to sequester yet more carbon from organic residues. A 2009/2/3 Alvia Gaskill <[email protected]>: > The real problem is not with the carbon dioxide emissions from the fuel. > It's with how much fuel has to be used and its cost. That is the argument > for starting with residue as close to deep water as possible, e.g. as > previously mentioned, eastern Japan and the Bay of Biscay off the west coast > of France. There are probably other locations as well that meet these > criteria. If a pipeline could be run from the coastal area to the deep > water, there would be no need for barging. Experience in the handling of > bagasse by sluicing can probably be applied to the CROPs strategy. > > ----- Original Message ----- > From: Stuart Strand > To: David Schnare > Cc: [email protected] ; [email protected] > Sent: Monday, February 02, 2009 4:34 PM > Subject: [geo] Re: Crop residue ocean permanent sequestration > > David, > > > > You are wrong about the carbon that would be emitted during transportation > of residues to the sea. Our calculation of 92% carbon sequestration > efficiency for CROPS is based on truck transport to the upper Mississippi > and barging to deep water in the Gulf. If you want a reprint please ask and > I will send. Nothing against no-till; it seems a good way to improve soil > fertility and not waste root carbon, but it is still a lossy way to > sequester above ground crop residue carbon. > > > > = Stuart = > > > > Stuart E. Strand > > 167 Wilcox Hall, Box 352700, Univ. Washington, Seattle, WA 98195 > > voice 206-543-5350, fax 206-685-3836 > > http://faculty.washington.edu/sstrand/ > > > > From: David Schnare [mailto:[email protected]] > Sent: Monday, February 02, 2009 9:04 AM > To: Stuart Strand > Cc: [email protected]; [email protected] > Subject: Re: [geo] Re: Crop residue ocean permanent sequestration > > > > Stuart: > > > > I've been studying notill agriculture that relies, in major part, on > building soil carbon to hold nutrients in the soil (reducing application > requirements and keeping it out of streams). While a 14% sequestration > (limited to only about 20 years before maxing out on sequestration > potential) seems small compared to 100% if dumped into the ocean deeps, it > seems to me that when used in places more than 150 miles from the ocean, it > is carbon reduction efficient (based on fuels needed for transport). > > > > As such, shouldn't we be narrowing the crop waste discussion to coastal > agriculture only, and give credit for soil sequestration where that's as > good as is available? > > > > David Schnare > > On Mon, Feb 2, 2009 at 11:54 AM, Stuart Strand <[email protected]> > wrote: > > By straw we are referring to the stalks of agricultural plants, wheat stalks > and corn stover. The water and nutrients were expended to grow the grain. > Straw has a low nutrient content (C/N = ca 50/1). Presently straw is wasted > by allowing it to decay on the soil surface (only 14% or less of the straw > carbon is incorporated into the soil). > > > > A variety of processes are available to get energy out of crop residues, but > they are limited by the poor specific energy of biomass. Our focus is how > to efficiently remove Pg amounts of carbon from the atmosphere and > permanently sequester it in the least environmentally harmful manner. > > > > = Stuart = > > > > Stuart E. Strand > > 167 Wilcox Hall, Box 352700, Univ. Washington, Seattle, WA 98195 > > voice 206-543-5350, fax 206-685-3836 > > skype: stuartestrand > > http://faculty.washington.edu/sstrand/ > > > > Using only muscle power, who is the fastest person in the world? > > Flying start, 200 m 82.3 mph! http://en.wikipedia.org/wiki/Sam_Whittingham > > Hour http://en.wikipedia.org/wiki/Hour_record > > 55 miles, upside down, backwards, and head first! > > > > From: [email protected] > [mailto:[email protected]] On Behalf Of > [email protected] > Sent: Wednesday, January 28, 2009 7:16 PM > To: [email protected] > > Subject: [geo] Re: Crop residue ocean permanent sequestration > > > > Stuart, > > > > Why bundle and stash terrestrial straw. Growing straw requires substantial > fresh water and nutrients. You could bundle and stash algae instead. How > about sargassum or kelp? A macro-algae can be bundled in large mesh "tea > bags" with much of the water being squeezed out during the bundling process. > > > > Then, as long as you've got bundles of biomass, why not separate the > nutrients from the carbon before you stash the carbon? That way, you can > recycle the nutrients back to the ocean surface for growing more biomass. > High-pressure anaerobic digestion will release the carbon in two separate > streams; one gaseous CH4, one dissolved CO2, which easily converts to liquid > CO2 at typical ocean temperatures and pressures. > > > > Would you or others be interested in a California Energy Commission grant to > run a few bench experiments on high-pressure anaerobic digestion? I can > send a draft abstract. > > > > > > Mark E. Capron, PE > > Oxnard, California > > www.PODenergy.org > > > > > > > > > -- > David W. Schnare > Center for Environmental Stewardship > > > > --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
