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Thank you coming to Athens and for the opportunity to share our work with you on biomass energy production with carbon utilization.  
Much of the technical data in my talk can be found in a paper accepted for publication this fall in the Energy the International
Journal. 
(http://www.eprida.com/hydro/ecoss/background/Energy_article.pdf)  In addition, a great deal the recent material on terra preta was taken from the June 2004 EACU conference in Athens, GA.  For complete access to conference materials, please drop me an email and I will assign you a membership login to the carbonnegative.info datacenter.  We provide this research oriented non-commercial datacenter to support the development and science of climate change management.
I have been working for the last few years with our Partners Institutions to pilot scale demonstrate pyrolysis with catalytic steam reforming for hydrogen production from biomass. The intent behind this work was to demonstrate a technology in the field, with typical workers, not Phd’s.  This is the team that built and ran the hydrogen production equipment.
We are now implementing a 1000 hour demonstration at the University of Georgia’s Bioconversion Research facility. In addition to producing hydrogen rich syn-gas, we will also be producing about 5 tons of a special type of charcoal.
Our pyrolytic unit was a thin bed cross flow reactor designed for granular materials.  It was preheated prior to the introduction of biomass.  Charcoal was used to fill the reactor and distribute heat.  One of my employees, Nate was instructed to bring a 55 gallon drum of charcoal from an area where we had produced and piled it up two years earlier.  He came back and asked what did I want to do with the plants.  I said “what plants?”  The plants growing on the charcoal, he replied.  I said “Nate, I need clean charcoal with no plants in them, just move them out of the way and get clean charcoal with no plants or root material in it.” He quickly went away.  The next day I was puzzled and asked Nate what kind of plants were growing in the charcoal. He said, “Oh grass, weeds, …. “  he paused, “and turnips”.  “Turnips? What kind of turnips” He smiled as he held up his hands about a foot apart and said, “Big turnips”.  I said,” Wow.  That’s incredible.  Go get me one”.  “I can’t”, he replied.  “Why not”, I asked. “You told me to move them”.  “where did they go?” Nate replied, “Charlie, Philip, David and I took them home”.  How much did you get? “We each got a big garbage bag full?”  What did they taste like I asked?  They were good! He said.  This was my first exposure to the charcoal effect but it hinted that perhaps nature had a mechanism for enhancing the soil by charcoal deposition.
Terra Preta refers to black high carbon (9%) earth-like anthropogenic soil with enhanced fertility due to high levels of soil organic matter (SOM) and nutrients such as nitrogen, phosphorus, potassium, and calcium. Terra Preta soils occur in small patches averaging 20 ha. These man made soils are found in the Brazilian Amazon basin, also in Western Africa and in the savannas of South Africa. C14 dating the sites back to between 800 BC and 500 AD. Terra Preta soils are very popular with the local farmers and are used especially to produce cash crops such as papaya and mango, which grow about three times as rapid as on surrounding infertile soils.
It is so valued it is dug up and sold as potting soil.  A highly significant finding by Bill Woods was that as long as a 20 cm layer of terra preta was left, the terra preta topsoil would regrow and could be harvested again in 20 years. The ability of terra preta to grow points toward a partnership solution with nature to solve our atmospheric carbon buildup.
This work by Julie Major from Cornell University provides a good example of why farmers prize this soil so much.
Measured carbon levels in terra preta soils confirm the higher carbon content of the dark black earth.
Ornate pottery is found throughout all terra preta soil indicating the presence of a highly civilized society.
Charcoal is found in all terra preta soils.
The information in the next few slides are from Dr. Ogawa in Japan.
This was presented by Dr. Ogawa
This slide was presented by Siregar from Indonesia.
Over the three years study an average yield increase of 49% was achieved.
Look at the rate of microbial growth in terra preta.
This is part of the secret of creating terra preta.  Smoldering fires produce a low temp char with bio-oil trapped inside.  High temperature fires drive off the oils as vapor and reduce charcoal to inert carbon with limited microbial effect.
Dr. Ogawa has shown the substantial increase in soil bacteria with the addition of charcoal. The ability to help support below ground development of microbial biomass can have large impacts on our global carbon levels.  The soil contains 4.2 times the amount of carbon as the atmosphere so factors that can increase and stabilize more carbon could be considered a second forest growing underground.
Glomalin’s is produced by one of the oldest forms of life on the planet. It’s spread contributed to production of the massive biomass which created our fossil fuel reserves.  Without glomalin we would have no oil or coal.  It is fitting that its growth may be the balance of the carbon equation for our planet.  It provides the glue that binds small particles and creates the feel of soft fertile soil. The impact on water retention and air holding capacity are similar to charcoal, and helps sustain microbial communities and biomass growth.
Charcoal has been shown to provide nutrients to fungi.
See the growth of mycorrhiza in the bottom picture with charcoal.
Dr Ogawa showed us this method for restoring a wilting pine tree.  He laughed at the conference and said this is old technology for the Japanese.
Dr Ogawa made the point that charcoal use for enhancing biomass growth is not experimental to the Japanese.  Their government has made it an officially approved crop and soil management practice.  Dr. Ogawa works for Kansai Environmental a division of Kansai Electric, which is one of the largest power companies in Japan.  They currently have projects in Australia and Thailand for utilizing charcoal addition to create carbon credits. Plans include a one million hector soil restoration project in Australia for growing cash crops and while creating carbon credits.
Christoph Steiner’s work is shown in the two pictures at left and demonstrate the effectiveness of a charcoal amendment.  The one on the right is from the Food and Fertilizer Technology Center which is showing the benefit of using rice hull char for enhanced agricultural production. Japanese researchers Kishimoto and Sugiura reported significant biomass increases in their study of charcoal addition to sugar trees. The increased cation exchange capacity, decreased leaching, increased water holding capacity and support for increased microbial growth provide inherent benefits for the use of char. It appeared that a porous carbon “land-reef” type soil amendment could offer increased crop yields sufficient to off set its alternate use in combustion and CO2 emitter. Our research began to develop a further value-add carbon material to be a carrier for essential nitrogen as well as a preferred microbial environment.
Pyrolytic conversion of biomass offer options and advantages
It is a well understood globally, where ever charcoal is made
Simple system improvements allow for the capture and use of pyrolytic off-gases (ex: Cars/Trucks in Sweden were converted to run off wood gas during WWII)
Pyrolytic conversion does not destroy the porous carbon structure created by nature
Pyrolysis is natural.  Nature has spent billions of years building systems and life forms that can take advantage conversion of biomass created by natural fires
Pyrolysis can offer some of the best economics for hydrogen (as well as bio-oil) production partly because of the options for co-product production*
Pyrolysis facilities can have reduced capital costs and small foot-prints
*Spath, et al, Update of Hydrogen from Biomass -Determination of the Delivered Cost of Hydrogen, National Renewable Energy Laboratory, Milestone Report for the U.S. Department of Energy’s Hydrogen Program 2001
This is an important chart and helps understand the hidden opportunities. A continuum of physical states exists in the stages of pyrolysis and charcoal formation.  First water evaporates, then non combustibles such as CO2 and acetic acid (the primary acid in vinegar).  Around 280 degrees C, Volatile gases and flammable tars are released. Many are condensable and will produce a liquid bio-oil.  Others are non-condensable, such as methane, are lost if not converted to heat or used to produce a usable fuel such as hydrogen. The smoke we see from fires, represents lost energy and more greenhouse gases. Between 280 and 500 represents a zone where biomass will continue to increase in temperature, even when no oxygen is present.  Above 400 C, most of the volatiles will have evaporated. Now here is an important note: Runkle and Wilke found that above 170 degrees, the volatiles gases would combined with other shorter chain molecules forming longer chain molecules with higher dew points that would condense inside the pore structures.  The process repeats over and over, perhaps thousands of times before complete devolitilization occurs. They called these polycondensates, others bio-oil, and some wood sugars.
Here we can see a typical thermogravimetric analysis.  The chart shows weight loss percent as the material is heated without oxygen present.  The dotted line shows the rate of weight loss in percent per min per 10 degrees C.  The step curve between 300 and 400 represents the exothermic zone. Each biomass produces a different chart. Now if we take these to charts and overlap them, let us see what happens.
The implications of utilizing the exothermic zone is that once started, biomass pyrolysis systems need not be energy consumers but rather when integrated into other processes can utilize heat as well as produce excess heat in a self sustaining mode.
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The next idea is that there are two inflection points on the rate of weight loss curve.  The beginning of the start of the exothermic range and the second inflection point is where rate of weight loss slows and the process tapers off to completion. Depending on particle size, zone 1 can be in minutes, seconds or hours for logs.  However, if there is no additional heat input from flames or glowing combustion of charcoal. The process will not extend far into zone 2. For extraction of oils for energy and co-products, the area under the curve in zone 2 has the highest cost.   If we consider that zone one is the optimal area for mankind’s utilization, then area under the curve in zone two may be Nature’s optimal are. It is as a small investment to provide a significant solution to reduce greenhouse gases, create a growing carbon sink, and the development of a sustainable world.
As I indicated smoke represents lost energy and in our case hydrogen. But before we continue, a quick glance at our current uses of hydrogen show that fertilizers consume a large part of the world’s hydrogen production. A sustainable hydrogen supply cannot be separated from agriculture as it forms a key link to delivered soil nitrogen. In other words hydrogen production for further processing into ammonia is a key component of our food production capability. Hydrogen does equal large scale food production.
In designing a charcoal to act as a media for carrying plant nutrients, ammonia adsorption is a large plus. Asada reports in 2002 that his experiments with bamboo char carbonized at low temperatures out performs even activated carbon.  He wrote that carboxyl acid groups formations natural to low temperature charcoal bind ammonia exceptionally well.
This proved out true in our own tests. We experimented with several different charcoals to determine a charcoal with properties suitable for carrying plant nutrients. The difference in the lowest temperature char still surprised us.  Most of my charcoal samples would stabilize after the 5 or 6th rinses.  But the one produced at 400C was still slowly releasing ammonia after 12 rinses.
In September of 2002 a patent for carbon sequestration with combined SOx and NOx was awarded to Oak Ridge National Labs. We met with them after their patent was granted in 2002 and proposed a test with a special char with which we were working.
In this case the gas phase hydrated ammonia is absorbed and converted into ammonium bicarbonate inside the charcoal pore structures.
In bench scale work at Oak Ridge National Laboratory the specially produced char combines with hydrated ammonia to for ECOSS and enriched carbon organic sequestering slow release matrix.
Our demonstration of the technology was conducted in pilot scale production unit.  Charcoal powder was fed into a simple mechanically fluidized reactor.
Within 10-15 minutes a heavy sand like material began to exit after having absorbed all the CO2, by speeding up the rotor we were able to produce a larger granular material with a higher nitrogen content, representing longer residence times. In this case all of our CO2 was converted. This system will also capture dust and fly ash materials, converting them into valuable soil conditioners.
In this scanning electron microscope image, we see the interior pore structures which offer safe haven for microbial colonies.  The plastic looking layer represents a coating of volatile organics, a food source.  The ability to balance the inert carbon percentage with the volatile organic compounds is an important aspect of the carbon-nitrogen delivery system.  It allows for flexibility so that if greater microbial activity is needed, an increased amount can be delivered with essential plant nutrients.  In addition, trace minerals are returned to the soil and represents the only way we believe to develop sustainable bioenergy production.
This simple diagram shows the process and profit centers. Those profit centers are exhaust scrubbing, fertilizer and fuel production.
The energy value of combustion has limited value yet after conversion into a stable form it can provide a greater lifetime value. The use as a scubbing agent plus the net present value of increased crop yield,  reduced fertilizer and water requirements.
CNE is energy produced where the net carbon emissions are lower than zero. For each 1Gj or MBTU approximately 112 kg of CO2 are utilized in a fashion where it does not return for centuries. This is a possible for fossil fuel energy use where carbon dioxide is sequestered and additional renewable Carbon is stored. Biomass makes CNE possible where biomass carbon is utilized in long lasting products. A soil carbon amendment provides for an almost limitless sink and is a very long lasting carbon product.
 
The loss of soil carbon is a major challenge to agriculture.  The emissions of carbon from human activities are a global issue that must be addressed in our lifetime.  These two problems have a common solution which creates a sustainable system for energy and agriculture.