Friday, January 15, 2010

On a new idea and a "What the hell?"

Scientists are reporting that “biochar” — a material that the Amazonian Indians used to enhance soil fertility centuries ago — has potential in the modern world to help slow global climate change. Mass production of biochar could capture and sock away carbon that otherwise would wind up in the atmosphere as carbon dioxide, the main greenhouse gas. Their report appears in ACS’ Environmental Science & Technology, a bi-weekly journal.

Kelli Roberts and colleagues note that biochar is charcoal produced by heating wood, grass, cornstalks or other organic matter in the absence of oxygen. The heat drives off gases that can be collected and burned to produce energy. It leaves behind charcoal rich in carbon. Amazonian Indians mixed a combination of charcoal and organic matter into the soil to improve soil fertility, a fact that got the scientists interested in studying biochar’s modern potential
I mentioned this when I wrote about 1491 a couple of years ago; it had a lot of information on the Amazon basin tribes using low, relatively 'cool' fires to burn pretty much anything organic they couldn't otherwise use to produce charcoal that, along with pottery shards, was dug into soil in areas to raise and enrich it for farming. Now, I may be missing something here, but they're basically saying
Take organic materials,
burn it to charcoal,
collect the gas produced so you can burn them for energy(to char the stuff, maybe?),
dig the charcoal into soil to enrich it.
Ok, so far, so good; but they're pushing this as a way of locking up that nasty carbon in gas form from the environment. By burning fuel to produce charcoal to...

Just as a side note: next to a picture of some charcoal there's this note:
Unlike familiar charcoal briquettes, above, biochar is charcoal made from wood, grass and other organic matter, and has the potential to help slow climate change.
And plain charcoal is made from, what? Unicorn farts and fairy droppings?


Chad said...

Now, that's some funny stuff right there. "But it's not charcoal, its 'BioChar' which sounds all scifi and stuff. So clearly it works better!"

martywd said...

Here I'll make it easy for ya'.   Just think of 'Biochar' as TACTICAL CHARCOAL.   ;-)

Daniel Newby said...

Charcoal is usually made hot, so it burns off the oxygen, nitrogen, and sulfur. What's left is pretty pure carbon, with the occasional mineral particle.

I suspect they're talking about biochar made at low temperatures, so lots of the non-carbon portion would remain. Those atoms are electrically charged and would make it pretty good at holding onto minerals. It would be like artificial humic acid, the brown gunk that makes rich soils rich. Adding a quarter inch of that a year to the soil would be a pretty neat trick.

And it's fairly hard to make charcoal out of things like grass and fur. There is a fine line between smoked versus ashed.