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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
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
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
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?
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
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
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
Over the three years
study an average yield increase of 49% was achieved.
Look at the rate of microbial growth in
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
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
of biomass offer options and advantages
is a well understood globally, where ever charcoal is made
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
can offer some of the best economics for hydrogen (as well as bio-oil) production partly because of the
options for co-product
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
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.
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
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.
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
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
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
This simple diagram shows the process
and profit centers. Those profit centers are exhaust scrubbing, fertilizer and
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
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.