Carbon Negative Biofuels also Increase Crop Production

Technocrat

Carbon Negative Biofuels also Increase Crop Production

zogger

Fri Jun 01 16:00:30 -0700 2007

Chemistry.

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This comes pretty close to fulfilling that old saying, "having your cake and eating it, too". Agrichar, or biochar, is the left over stabilized charcoal-like product from the pyrolysis of biofeedstock matter in the production of alternative fuels. This agrichar has been shown to vastly increase soil fertility, meaning a lot more crops starting with the first season, and to remain stable and remain in the soil for years to decades or beyond, effectively trapping more carbon that what was used to produce it and the fuels. Better than mulch or compost actually, as those break down quickly. It is carbon negative in other words, even better than the pushed goal of "carbon neutral".

..."Trials of agrichar - a product hailed as a saviour of Australia’s carbon-depleted soils and the environment - have doubled and, in one case, tripled crop growth when applied at the rate of 10 tonnes per hectare."..more there

ed: I was doing something very similar to this in the mid 70s, with a woodstove integrated with a woodstove. The lower chamber burned normally, while the upper chamber was a lot more airtight and burned the released methane much more efficiently, and that is where I got most of the heat. The lower heated the upper in other words. And I did turn the left over charcoal like stuff into the garden soil(the lower made normal looking ashes, the upper looked like charcoal), and did get some amazing crops there. I had no name for the process or the "agrichar", just thought I could heat my little abode better and save on back breaking firewood harvesting with handsaw and ax....oh well, glad to see this! This is some *neat tech*. Good biofuel plus improved soil fertility with a "waste" product at the same time while sucking more carbon out of the air is a fantastic good innovation.

Carbon Negative Biofuels also Increase Crop Production

wowbagger

Fri Jun 01 18:17:53 -0700 2007
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Now, if we could combine agrichar with basic stuff like crop rotation, including nitrogen fixing crops, we might be able to weed the American farmer off the intensive use of fertilizer (produced with petroleum products) and get back to the idea of "harvesting sunlight".
Plus, I'd be willing to bet this helps the soil be able to hold more moisture longer, thus reducing irrigation needs (so long as there is a modicum of rain).
My house sits on land that used to be farmland for many long decades - the soil is so hammered by intensive farming that it is a few inches of very compacted "topsoil" which is mostly clay, on top of real clay. I'd love to be able to bring in several tons of *any* organic material to help revive the soil.
Now if we could just find an efficient oil-bearing crop that fixes nitrogen.

Carbon Negative Biofuels also Increase Crop Production

TykeClone

Sat Jun 02 06:24:48 -0700 2007
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Carbon != Nitrogen which is the bulk of most commercial ag fertilizers.

As far as the "farmland" under your house, I've read that one of the first things that home builders do is to scrape up the good black dirt and sell that - and only leave the poorer subsoil for the new homeowner.

Carbon Negative Biofuels also Increase Crop Production

wowbagger

Sat Jun 02 06:35:26 -0700 2007
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First of all, I never equated carbon and nitrogen — it is just that BOTH elements are a problem in modern agriculture.
Second of all, I'd not believe everything you read, nor would I assume that what you read holds true in all cases. I know in this case the "soil" is indeed what was being farmed.

Carbon Negative Biofuels also Increase Crop Production

TykeClone

Sat Jun 02 06:47:08 -0700 2007
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Must be different parts of the country then. Not all farmland is created equal. When I've traveled outside of Iowa, I'm often amazed at the kind of soil people attempt to grow crops in.

Carbon Negative Biofuels also Increase Crop Production

turtledawn

Sun Jun 03 16:24:10 -0700 2007
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You work with what you've got available.

The dirt in North Carolina still scares me, though- it's pink.

Carbon Negative Biofuels also Increase Crop Production

President4242

Mon Jun 04 10:24:02 -0700 2007
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As far as the "farmland" under your house, I've read that one of the first things that home builders do is to scrape up the good black dirt and sell that - and only leave the poorer subsoil for the new homeowner.

They'd have to scrape rather low in my area- thanks to the Missoula Flood, topsoil around here bottoms out at 200 feet deep.

Carbon != Nitrogen, but it does trap nitrogen

David Leppik

Mon Jun 04 13:25:45 -0700 2007
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Here I am, replying again without reading the post... but I did read something similar several months ago. Apparently this is a real world "secret of lost civilizations"... as they've found this sort of thing in sections of the Amazon River basin-- and the soil is still exceptionally fertile.
When you bury charcoal, the carbon isn't consumed by plants. It stays there, permanently. Hence it's "carbon negative." It's essentially a carbon filter, just like the ones used to purify drinking water. Nutrients get trapped by the charcoal, rather than escaping in the runoff. So you can use less fertilizer, and you get cleaner rivers and streams as well. The only downside is that any toxins that get dumped in the soil stick around too.

Carbon Negative Biofuels also Increase Crop Production

Bruce Perens

Fri Jun 01 21:16:51 -0700 2007
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Left-over methane not getting burnt in the lower chamber? Well, maybe. But could it have been carbon monoxide from incomplete combustion? It's the original heating gas.

Carbon Negative Biofuels also Increase Crop Production

zogger

Mon Jun 04 18:35:19 -0700 2007
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Near as I could tell I was getting a good flow of combustible gases from the upper, they hit the already burning stream from the lower less efficient chamber and ignited. The ashes/waste were really different looking. I didn't have any sensors or anything (I mean, this was some low tech sheet metal stuff I cobbed together), so I have no way of knowing what I was getting besides a lot more heat from what I recalled previously per unit volume of similar wood. Modern expensive woodstoves are built roughly similar as to ultimate heat output, just using a longer gas travel (they use baffles now a lot) and better regulation of air intake and postive air flow over the heat exchanger part of the deal (electric fans in other words), but they still don't use separate chambers which is the key point. I think if you got the procedure going with two chambers, once it got hot enough and was really flowing you could divert the exhaust from the heated chamber and just shutoff/starve the preheating chamber, divert your gases from the upper there,(loop it) and get even better efficiency, as it would be preheating *itself*, like the oven in old cookstoves looped the gases around.
With that said, I am *still* of the opinion earth bermed and superinsulation is a much better idea for heating and cooling for the long term, you just can't beat passive geothermal. Build once, enjoy forever. As opposed to build once, keep feeding some sort of fuel forever that costs you money/time/effort.