Researchers find renewable energy leftovers could fertilize, cut carbon emissions

Sep 30, 2010 by Stu Hutson

(PhysOrg.com) -- For hundreds of years, farmers in Brazil's Amazon Basin have hunted through dense jungles for what is called "terra preta" — mysterious plots of super-fertile black soil amid otherwise nutrient-stripped earth.

In recent decades, researchers have discovered that the rich properties of terra preta stem from the carbon-heavy leftovers of ancient cooking sites. Now, University of Florida researchers have found we can make our own version of the soil’s potent component, a form of charcoal dubbed biochar, from the remnants of production.

“This could possibly improve the viability of certain biofuels by giving a valuable — both economically and environmentally - byproduct from material that would otherwise just be a disposal problem,” said Bin Gao, an assistant professor of agricultural and at UF’s Institute of Food and Agricultural Sciences.

For example, a renewable form of natural gas can be produced by “digesting” organic material with the help of added bacteria. As they report in the November issue of the journal Bioresource Technology, Gao and a team from UF found that, using inedible portions of sugar cane as , the sludge material left over from this process can then be turned into useful forms of biochar.

The biochar is created through a process called flow pyrolysis, in which plant matter is broken down by exposure to temperatures up to 650 degrees Fahrenheit in a container without much oxygen. This means the carbon-heavy components of the material can’t burn, but are freed up in the blackened leftovers.

Whereas the leftovers from the production would normally need to be treated and disposed of as waste material, biochar can instead be used to augment infertile soil by absorbing pollutants, leveling acidity, improving water retention and reducing the leaching of nutrients.
Biochar has another important property — it can be used to sequester carbon and thus reduce emissions that contribute to the greenhouse effect.

“When you add biochar to the soil, it’s likely that as much as 90 percent of that carbon is still going to be in that soil a hundred years from now if left undisturbed,” said Andrew Zimmerman, UF assistant professor of geological sciences and co-author of the study.
Some studies have indicated that converting all agricultural waste biomass to biochar could reduce carbon emissions by as much as 12 percent, Zimmerman said.

Biochar production can be integrated with other methods of producing biofuels. But more study is needed to understand how to produce biochar suitable for agricultural use, the researchers say.

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erich_knight
1 / 5 (4) Oct 02, 2010
Recent NATURE STUDY;
Sustainable biochar to mitigate global climate change
http://www.nature...053.html

Not talked about in this otherwise comprehensive study are the climate and whole ecological implications of new , higher value, applications of chars.

1
the in situ remediation of a vast variety of toxic agents in soils and sediments.
http://www.bioren...ent.html

Dr. Lima's work; Specialized Characterization Methods for Biochar at USDA;
The Ultimate Trash To Treasure, Research Turns Poultry Waste into Toxin-grabbing Char
2
the uses as a feed ration for livestock to reduce GHG emissions and increase disease resistance.

3
Recent work by C. Steiner showing a 52% reduction of NH3 loss when char is used as a composting accelerator. This will have profound value added consequences for the commercial composting industy
erich_knight
1 / 5 (4) Oct 12, 2010
Agriculture allowed our cultural accent and Agriculture will now prevent our descent.

Wise Land management; Organic farming and afforestation can build back our soil carbon,

Biochar allows the soil food web to build much more recalcitrant organic carbon, ( living biomass & Glomalins) in addition to the carbon in the biochar.

Every 1 ton of Biomass yields 1/3 ton Charcoal for soil Sequestration (= to 1 Ton CO2e) + Bio-Gas & Bio-oil fuels = to 1MWh exported electricity, so is a totally virtuous, carbon negative energy cycle.

Biochar viewed as soil Infrastructure; The old saw;
"Feed the Soil Not the Plants" becomes;
"Feed, Cloth and House the Soil, utilities included !".
Free Carbon Condominiums with carboxyl group fats in the pantry and hydroxyl alcohol in the mini bar.
Build it and the Wee-Beasties will come.
Microbes like to sit down when they eat.
By setting this table we expand husbandry to whole new orders & Kingdoms of life.