Bury charcoal to sequester CO2?

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Rimu
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Joined: 17 May 2008
Bury charcoal to sequester CO2?

According to James Lovelock via NewScientist:

"There is one way we could save ourselves and that is through the massive burial of charcoal. It would mean farmers turning all their agricultural waste - which contains carbon that the plants have spent the summer sequestering - into non-biodegradable charcoal, and burying it in the soil. Then you can start shifting really hefty quantities of carbon out of the system and pull the CO2 down quite fast.

The biosphere pumps out 550 gigatonnes of carbon yearly; we put in only 30 gigatonnes. Ninety-nine per cent of the carbon that is fixed by plants is released back into the atmosphere within a year or so by consumers like bacteria, nematodes and worms. What we can do is cheat those consumers by getting farmers to burn their crop waste at very low oxygen levels to turn it into charcoal, which the farmer then ploughs into the field. A little CO2 is released but the bulk of it gets converted to carbon. You get a few per cent of biofuel as a by-product of the combustion process, which the farmer can sell. This scheme would need no subsidy: the farmer would make a profit."

It sounds easy and low-tech, but I have no idea how much charcoal you'd need to make and in what time frame...?? What are your thoughts on this?

Richard
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Joined: 4 Jul 2008
Biochar....Now we are talking!

Great to here that you have stepped out of the headlights Rimu! The high speed global monolith screaming out of control does have the knack of dazzling you  into submission. I often wonder if like a possum caught in the headlights, the louts that are driving that suped up engine are actually intending to run us all down.

But when you do step out of that Shadow it is staggering just HOW MUCH there is available for active communities to create a more sustainable world. Sequestering carbon as charcoal is a very good example of a simple technology that is easily available to us and has been around for bloody ages. This process is very similar to the wood gasification process which captures the hydrogen given off by the charcoal and was used to power motor cars after the first world war.

But like so many of the examples that fall into that simple UNPATENTABLE tried and true catergory (biogas and ethanol are two others), they will probably have to be initaited by active communities rather than waiting for corporates and government to do the job. The BIG bucks just aren't there when you can't own the intellectual property, so the research just doesn't get dione.

 I think its really important that we view examples like Biochar as tool basket to create transition strategies and actions that help to minimise the inevitable energy contractions rather than simply seeing them as a "technofix". Such strategies can mesh perfectly with community currencies, gardens and other work that TTers do.

There is quite a lot of work being done on Biochar already in NZ. The Kaiwaka TT group have had workshops on Biochar making and I believe there is a Biochar study group that in the past has been funded by the Climate Change arm of the Sustainable Farming Fund  that is looking at developing localised grid interactive electricity systems to capture the energy from the Biochar whilst providing a beneficial soil additive.

From memory Greg pahl's Citizen Powered energy handbook touches on it breifly

great stuff.

 

Cheers

Rchard

 

 

gyrogearloose
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Joined: 11 Feb 2009
Pyrolysis

Spent the last year desigining and building a plant in auckland to pyrolyse tryes.

All the carbon frm the plant is due to go to feed the pacific steel mill.

Target of 20 ton per day of tyres.

Back in ChCh now, and looking to get involved with TT efforts.

 

Cheers Hamish

Richard
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Joined: 4 Jul 2008
Pyrolysis

Sounds interesting...tell us more

 

cheers

Richard

gyrogearloose
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Joined: 11 Feb 2009
Pyrolysis

Hi Richard

Have been test running the plant, which consists of

A 13 m^3 gasometer,

60,000 L of tanks ( on site but yet to be installed )

3 X 40 ft containers standing on end,

one as a pyrolysis module ( with a burner unit almost the size of a 20 Ft container beside it)

one as a stairwell

One containing distillation and seperation gear.

each pyro module ( a 40 Ft container ) should be able to handle 6-7 ton of tyers per day. ( from test run data )

Testing showed that the bottom set of airlock doors need to be redesigned.  Rest of the plant behaving well.

Plant is run off the "waste" gas stream.

Products light fuel oil, volatile solvent mix, carbon, steel wire.

Steel mill look like they will take the carbon and steel mix as it comes out of the plant ( test batches performed well )

LFO easy to sell, volatile solvent mix a bit of an orphan at present.

They have run out of money and currently looking for more.

 

 

In another thread you mentioned about raupo, I was rather surpised at the yeild of alcohol.

What is involved in collection etc if you were using it as a crop.

 

I am new to TT, found it through Chris Martenson and the crash course, which I found while digging into resource depletion  that was starting to impinge on my mind 2 years ago.

Cheers Hamish

 

 

 

 

Richard
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Joined: 4 Jul 2008
Raupo to ethanol

Hi Hamish,

Welcome aboard. Sounds like you may have some valuable skills that transition could use.

I was rather surprised at the yields that may be possible from Raupo myself. Its worth stating though that yields are from the American species of Raupo Typha latifolia. We have Typha orientalis so the yields may differ. I have heard of one study that indicates that the yields are likely to be similar but really not enough studies have  been done on our species yet to give a definitive answer.

If the yields do work out to be similar harvesting is the big question. In the American species the white fleshy base of the Typha contains about 25% starch, the roots contain 75%. Harvesting the roots is very difficult but has been done with  modified potato and oyster harvesting equipment.

However David Blume suggests that its easiest just to harvest the fleshy base and leave the roots insitu so that you get a quicker turn around of crop. He suggests growing the Typha in a long 1 foot deep trench with a hard pad next to it. At harvest drain off the trench and drive a tractor down along the side with a boom mulcher and catcher. Mow off the green leafy top, which goes to the compost. On the 2nd pass mow the the starchy base down to ground level, which then goes to your fermentaion and distillation unit.

Such a system could be incorporated into contour swales that could be used to catch nutrient laden farm run-off. That way your Typha is getting the fertiliser it needs to produce the large yeilds required to make the process viable. Such a system would also reduce the amount of nutrient enetering and polluting rural waterways. Thus giving a win/win outcome.

 

Cheers

Richard

 

 

 

 

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