states that we need to soon reduce atmospheric CO2 from the
current 385 ppm to an initial 350 ppm for compelling reasons.
Here is an outline of a plan for doing so.
The world economy is about 67 trillion dollars (GDP).
Imposing a VAT of 1% raises then 670 billion dollars per year.
This sum is used to grow biomass, convert it to biocoal, and
sequester the biocoal in carbon landfills, every year until
the goal of 350 ppm is met.
Using Powder River Basin style earth movement, it would cost
about $16.50 per tonne to sequester the biocoal. In addition,
the biomass must be harvested, moved to the hydrothermal
carbonization facility, converted to biocoal (while generating
some process heat for electricity generation), and then the
biocoal moved to the landfill site. By conducting all these
operations in parts of the world with ample excess land and
low-cost labor (Africa) I will assume these steps can be done
for only $33.50 per tonne, under half the amount required in
the developed world. Thus the carbon capture and
sequestration net costs are assumed to be $50 per tonne of
biocoal.
I will assume, for simplicity, that the biocoal is 85% carbon.
Humans are currently adding about 8.5 gigatonnes of carbon
(GtC) to the active carbon cycle per year, mostly by burning
fossil carbon. Just to maintain the current 385 ppm of
atmospheric CO2 then requires producing and sequestering
10 gigatonnes of biocoal per year. This costs $500 billion
per year, leaving a net of $170 billion available for
producing and sequestering additional biocoal to reduce the
concentration of CO2 in the atmosphere.
To reduce the concentration to 350 ppm requires removing
about 185 GtC from the active carbon cycle. At the rate
of ian additional 3.4 gigatonnes of biocoal per year, using
the net funds available, we would remove 2.89 GtC from the
active carbon cycle each year. Assuming this is done at
a steady rate, it will require 64 years to bring about the
desired initial atmospheric CO2 concentration of 350 ppm.
M.-M. Titrisci, et al.,
Back in the Black: hydrothermal carbonization of plant
material as an effiecient chemiccal process to treat the CO_2
problem?
New Journal of Chemistry, 207, 31, 787--798 (25 references). (Linked
below)
On 19/03/2008, David B. Benson <dben...@eecs.wsu.edu> wrote:
> I will assume, for simplicity, that the biocoal is 85% carbon. > Humans are currently adding about 8.5 gigatonnes of carbon > (GtC) to the active carbon cycle per year, mostly by burning > fossil carbon. Just to maintain the current 385 ppm of > atmospheric CO2 then requires producing and sequestering > 10 gigatonnes of biocoal per year.
It's not as bad as that, actually. A large chunk of what we are currently producing is being soaked up by oceans and biomass. So we only need to sequester about half of gross emissions to stabilise atmospheric CO2, and anything more will cause a decline. Of course this sink will not last for ever (the ocean will saturate) but it does reduce the scale and urgency of the issue (setting aside for now whether this sort of target is sensible in the first place).
On Mar 18, 10:12 pm, "James Annan" <james.an...@gmail.com> wrote
...
> A large chunk of what we are
> currently producing is being soaked up by oceans and biomass. So we
> only need to sequester about half of gross emissions to stabilise
> atmospheric CO2, and anything more will cause a decline. ...
> James
Thanks. I ignored this point under the assumption that as the decline
begins, the ocean, land and biomass will all give up some of the
excess CO2 to maintain equilibrium. Of course, water with excess CO2
which descends into the deep ocean won't be seen for quite a long
time, but I have assumed (this may be long) that very little has gone
deep yet.
If emissions were halved (which is the equivalent of James' suggetsion) I don't expect that concentrations would stabilize.
The details are complicated, but as I understand it, to first order an excess unit of CO2 on decadal time scales has a 50% chance of ending up in the biota or the ocean. That is, the biota and the ocean are equilibrating to the excess, not to the amount. Accordingly David's approximation seems much better to me than James' does. (Such drawdown as exists is on millenial time scales and is thus of second order on the time scale of interest here.)
David, am I reading correctly that you are proposing sequestering the biocoal directly? Why not burn it and sequester the CO2 instead?
Also, you get a third of your cost back because you are replacing coal which is not free.
On Mar 20, 1:01 pm, "Michael Tobis" <mto...@gmail.com> wrote:
> ...
> David, am I reading correctly that you are proposing sequestering the
> biocoal directly? Why not burn it and sequester the CO2 instead?
> ...
Many variations are possible. This sketch-of-a-plan has the advantage
of not only being easy to explain, but surely providing safe, secure,
permanent sequestration. Sequestering CO2 does not offer that high
assurance at this time.
The price of coal is now high enough (see Wednesday's TNYT) that
investors ought to be seriously considering making biocoal to compete
in the metalugical anthracite market. Looks to me there is money to
be made, in a carbon-neutral fashion.
David B. Benson wrote: > The price of coal is now high enough (see Wednesday's TNYT) that > investors ought to be seriously considering making biocoal to compete > in the metalugical anthracite market. Looks to me there is money to > be made, in a carbon-neutral fashion.
There was an interesting article in NewScientist a few months ago, suggesting that "peak coal" may also be upon us rather earlier than many official estimates (and for similar reasons).
"THERE used to be a saying about taking coal to Newcastle, but these days the issue is getting the stuff out. Newcastle in New South Wales, Australia, may be the biggest coal export terminal in the world's biggest coal-exporting country, but even it is having trouble keeping up with demand. The line of ships waiting to load coal can stretch almost to Sydney, 150 kilometres to the south. At its peak last year, there were 80 vessels in the queue, each forced to lie idle for up to a month.
"The delays have been increasing since 2003, and not just because of the port's limited capacity. Gnawing doubts are also beginning to emerge about the supply of coal, not just in Australia but worldwide, and not only because of logistics but also because of geology. In short, coal may be running out."
From: "David B. Benson" <dben...@eecs.wsu.edu> Newsgroups: gmane.science.general.global-change To: "globalchange" <globalchange@googlegroups.com> Sent: Tuesday, March 18, 2008 5:08 PM Subject: [Global Change: 2477] nding Global Warming via Biocoal Sequestration
> the biomass must be harvested, moved to the hydrothermal > carbonization facility, converted to biocoal (while generating > some process heat for electricity generation), and then the > biocoal moved to the landfill site. By conducting all these > operations in parts of the world with ample excess land and > low-cost labor (Africa) I will assume these steps can be done
Two potential flies gathering around the ointment: land management and labor management.
The price of charcoal in Africa is skyrocketing due in part to supply restrictions brought about by bans on traditional charcoal producers' deforestation practices. The charcoal market is sending a clear signal: Africa needs to produce more charcoal (or a cheaper, more suitable substitute). But sustainable forestry policy demands that this be done as efficiently as possible, with attention to reforestation and biodiversity preservation.
Building a modern capital-intensive mechanized biocoal industry in the tropics (e.g. a Million Herreshoff Furnaces) will be challenging, and not least of the challenges will be social equity concerns for workers displaced from the traditional charcoal industry by mass production of low-cost biocoal. With livelihoods at stake, there is potential for social conflict if the benefits of industrialization are not shared fairly. The history of industrialization in the developed world has taught us that there should be equal power-sharing between the interests of capital and labor, which requires establishing respect for the rule of law to avoid open conflict. The history of industrialization in the developing world has taught us this is not always so.
This brings us to fly number two: slavery in charcoal camps. Charcoal is used extensively to produce pig iron in Brazil, and slavery has been documented. Respect for human rights and the rule of law are sometimes lacking in tropical forests where industrial production under conditions of extreme poverty is concerned. It is a challenge to ensure that the biofuels and carbon offset industries play by the rules in developing countries. We should move forward to meet that challenge in the tropics, and also consider the potential to grow these industries in temperate climates, where the regulatory framework for socially just and ecologically sustainable industrial forestry is better established. If the agribusiness marketing machine can be turned on to Agrichar, then we may begin burying charcoal on a large scale, at a profit.
First, biocoal is made via hyrothermal carbonization, basically a
pressure cooker. So no Herreshoff Furnaces are used.
Second, I certainly agree that sound, healthy practices are required.
Third, there is an abundance of suitable, non-arible, unforested land
elsewhere in Africa than in the tropics. The entire Sahel, most of
Madagascar, most of Nambia, etc.
From: "David B. Benson" <dben...@eecs.wsu.edu> Newsgroups: gmane.science.general.global-change To: "globalchange" <globalchange@googlegroups.com> Sent: Sunday, March 23, 2008 1:32 PM Subject: [Global Change: 2485] Re: nding Global Warming via Biocoal Sequestration
> Don Libby:
> First, biocoal is made via hyrothermal carbonization, basically a > pressure cooker. So no Herreshoff Furnaces are used.
It's not clear to me what advantage biocoal batch production via pressurized hydrothermal carbonization would have over continuous char production via fast or slow pyrolysis for the purpose of landfilling or soil amendment.
For example, here is a company with a continuous fast pyrolysis process developed to the point of early commercialization, which produces char as well as liquid and gaseous fuels from a variety of feedstocks: http://www.dynamotive.com/ .
It would seem to me that char produced by pyrolysis in Ontario would serve the carbon sequestration purpose at least as well as biocoal produced by hydrothermal carbonization in Namibia, no?
On Mar 24, 1:25 am, "Don Libby" <dli...@tds.net> wrote:
> ...
> It would seem to me that char produced by pyrolysis in Ontario would serve
> the carbon sequestration purpose at least as well as biocoal produced by
> hydrothermal carbonization in Namibia, no?
No. Biocoal is, afterall, just high-grade coal. We know it
will stay unchanged in the ground for millions of years. That
may not be true of biochar. It certainly is not when applied
as a soil amendment. See this survey report:
The other problem is cost, primarily that of collecting the
biomass and transporting it to the reactor (which might be
hydrothermal carbonization, torrifaction, or pyrolysis). The
costs in Africa will be substantially less than in Ontario.
Do note that in my original post starting this thread, I
provided several links regarding biocoal. One is to an
article about a demonstation plant in The Netherlands which
produces 75,000 tonnes per year. It doesn't appear that batch
versus continuos is an issue.
> No. Biocoal is, afterall, just high-grade coal. We know it
> will stay unchanged in the ground for millions of years. That
> may not be true of biochar.
Biocoal is a term used by different companies and institutes, which
includes my own institutiton, namely the Energy Research Centre of the
Netherlands#.
