December 13th, 2008 · 1 Comment
By Julie Bonnin and Barbara Kessler
Green Right Now
At this time of year, when many municipalities are gearing up for holiday tree recycling programs, the city of Houston is dealing with something far more monumental – more than 5.6 million cubic tons of tree waste left behind after Hurricane Ike swept through Southeast Texas in early September.
The city turned some of the debris into mulch, but launched a contest in October, Recycle Ike, to spark ideas for keeping the remaining tree waste from simply being disposed of in landfills.
The winners, announced last week, are a Rice University team of students and scientists who will create a biomass charcoal from the tree remains. The group was among more than 200 entrants from around the world that submitted ideas.
The top $10,000 prize will be used to build a pilot bioreactor on campus. The “biochar” it produces helps the environment in three ways – as a soil enrichment; as a way to stop the decaying waste from releasing carbon into the atmosphere from the decaying wood; and as a method for producing methane gas during the conversion process which can be sold to generate energy.
Using a process called pyrolysis, the bioreactor will heat the biomass tree waste to 400-500°C under low-oxygen conditions to produce the biochar, according to a report by the Rice University team.
“Approximately 50% of the carbon in the feedstock biomass is captured in the biochar, which can be used to sequester carbon in soils. Biochar is carbon-rich and chemically stable in soils, enabling carbon to be
sequestered in soils for centuries or millennia. In addition, biochar improves soil fertility by improving water holding capacity and cation exchange capacity,” the report states.
The methane gas produced during the heating process will be captured and used to generate electricity.
If the pilot project works as projected, it argues for using pyrolysis to deal with all of Hurricane Ike’s considerable waste, say the plan’s proponents. (Ike was the fourth most destructive hurricane to hit the United States.)
“Applied to the entire Hurricane Ike biomass debris, pyrolysis has the potential to sequester more than 1,000,000 metric tons of CO2 and offset an additional 280,000 metric tons of CO2 through the use of syngas [the methane] to generate electricity, removing the equivalent of 300,000 cars from Houston’s roads for a year,” according to the Rice report.
Next, pyrolysis could help the city of Houston more efficiently deal with its ongoing organic waste needs, the researchers say. By turning biomass into soil-enriching biochar and capturing the methane gas for electricity production, they estimate that the city could save carbon emissions equivalent to taking 17,000 cars off the road annually.
The Rice team is nothing if not enthusiastic, concluding: “As a leader already in energy and medicine, the city of Houston stands to become a leader in sustainability. By adopting pyrolysis to handle the Hurricane Ike debris and its annual waste stream, Houston can position itself to be at the forefront of the movement to reduce CO2 emissions and actively remove CO2 from the atmosphere…Ultimately, biochar production promises to revolutionize green waste management in Houston, combining sustainability with a global environmental outlook.”
1 response so far ↓
1 erich // Dec 14, 2008 at 12:28 pm
Biochar, the modern version of an ancient Amazonian agricultural practice called Terra Preta (black earth), is gaining widespread credibility as a way to address world hunger, climate change, rural poverty, deforestation, and energy shortages… SIMULTANEOUSLY!
Modern Pyrolysis of biomass is a process for Carbon Negative Bio fuels, massive Carbon sequestration,10X Lower Methane & N2O soil emissions, and 3X Fertility Too.
Every 1 ton of Biomass yields 1/3 ton Charcoal for soil Sequestration, Bio-Gas & Bio-oil fuels, so is a totally virtuous, carbon negative energy cycle.
Charles Mann (”1491″) in the Sept. National Geographic has a wonderful soils article which places Terra Preta / Biochar soils center stage.
I think Biochar has climbed the pinnacle, the Combined English and other language circulation of NGM is nearly nine million monthly with more than fifty million readers monthly!
We need to encourage more coverage now, to ride Mann’s coattails to public critical mass.
Please put this (soil) bug in your colleague’s ears. These issues need to gain traction among all the various disciplines who have an iron in this fire.
http://ngm.nationalgeographic.com/2008/09/soil/mann-text
I love the “MEGO” factor theme Mann built the story around. Lord… how I KNOW that reaction.
I like his characterization concerning the pot shards found in Terra Preta soils;
so filled with pottery – “It was as if the river’s first inhabitants had
thrown a huge, rowdy frat party, smashing every plate in sight, then
buried the evidence.”
Biochar data base;
http://terrapreta.bioenergylists.org/?q=node
I also have been trying to convince Michael Pollan ( NYT Food Columnist, Author ) to do a follow up story, with pleading emails to him
Since the NGM cover reads “WHERE FOOD BEGINS” , I thought this would be right down his alley and focus more attention on Mann’s work.
I’ve admiried his ability since “Botany of Desire” to over come the “MEGO” factor (My Eyes Glaze Over) and make food & agriculture into page turners.
It’s what Mann hasn’t covered that I thought should interest any writer as a follow up article and your transition team
The Biochar provisions by Sen.Ken Salazar in the 07 & 08 farm bill,
http://www.biochar-international.org/newinformationevents/newlegislation.html
NASA’s Dr. James Hansen Global warming solutions paper and letter to the G-8 conference, placing Biochar / Land management the central technology for carbon negative energy systems.
http://arxiv.org/ftp/arxiv/papers/0804/0804.1126.pdf
The many new university programs & field studies, in temperate soils; Cornell, ISU, U of H, U of GA, Virginia Tech, New Zealand and Australia.
Glomalin’s role in soil tilth, fertility & basis for the soil food web in Terra Preta soils.
The International Biochar Initiative Conference Sept 8 in New Castle;
http://www.biochar-international.org/ibi2008conference/aboutibi2008conference.html
Given the current “Crisis” atmosphere concerning energy, soil sustainability, food vs. Biofuels, and Climate Change what other subject addresses them all?
This is a Nano technology for the soil that represents the most comprehensive, low cost, and productive approach to long term stewardship and sustainability.
Carbon to the Soil, the only ubiquitous and economic place to put it.
Michael Pollan is well briefed about Biochar technology, but did not include it in his 8000 word, “Farmer & Chief” NYT’s article to President Obama, but I’m sure Biochar will be his 8001th word to you.
Erich
540 289 9750
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