Biochar: Recycling Waste Biomass to its Highest Value Use

MassRecycle’s University of Resource Management and 10th Annual Organics Recycling Summit

April 6, 2010

Hugh McLaughlin, Ph.D., P.E.Director of Biocarbon Research

Alterna Biocarbon Inc., div of Alterna Energyhmclaughlin@alternabiocarbon.com

www.alternabiocarbon.com

Dr. Johannes Lehmann is in the Department of Crop and Soil Sciences, Cornell University

UndistinguishedColleague

So given a certain amount of carbon that cycles annually through plants, half of it can be taken out of its natural cycle and sequestered in a much slower biochar cycle (see graphic). By withdrawing organic carbon from the cycle of photosynthesis and decomposition, biochar sequestration directly removes carbon dioxide from the atmosphere.

This is the tree as it grows.About one half of the carbon dioxide uptake results in additional carbon atoms in biomass

This is when biomass dies and becomes detritus: such as leaves and tree death

This is due to microbial breakdown of dead biomass – 95% in one to twenty years

Pyrolysis and Carbonization convert biomass into biochar: one half of the carbon atoms are released as volatiles and one half converted to biochar

The volatiles contain carbon atoms that the tree removed from the atmosphere as it grew = carbon neutral

A minority of biochar is slowly oxidized by soil microbes; the majority is stable for hundreds to thousands of years

Hang on tight, we need to go from:

Trees and Grasses to – Lignocellulosic biomass to –

lignin and sugars to – char to – biochar

– in less than Twenty Minutes …..

From: http://www.techtp.com/Torrefaction for High Quality Wood Pellets.pdf, page 7 of 36 

Wood Physical Structure – from tree to molecules of lignin & sugars

From: http://www.techtp.com/Torrefaction for High Quality Wood Pellets.pdf, page 7 of 36 

Wood Microscopic Structure – molecular mixtures at the atomic scale

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drying (A)

ExtensiveDevolatilisation

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carbonisation(E)

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andcarbonisation (D)

depolymerisationand

recondensation(C)

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Hemicellulose Lignin Cellulose

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From page

Amorphous Graphite = Domains of Graphene

8

Consolidation into local Graphene domains during carbonization

Page 3 of J. Phys.: Condensed Matter 19 (2007) 9

Additional carbonization develops a porous 3-dimension structure

Principal Constituents of Biochar:

• Moisture (as delivered)• Moisture is not a bad thing, but it is not

worth paying for ……• Moisture is added after char production,

usually to cool or passivate the char• Moisture in the bag does not mean the

char will have superior moisture retention in soil – it means moisture was added …

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Principal Constituents of Biochar:

• Moisture (as delivered)• Ash (as delivered and from what)

• Converting Biomass to Char removes the moisture and much of the organic portion, but very little of the ash constituents

• Ash levels are 3 to 4 times that of the dry pre-carbonization biomass

• Soluble Ash is the principal pH effect of biochar addition to soils – can act like lime

• Ash includes Nitrogen? – depends on test

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Resident Carbon Resident H & O Resident Nitrogen Mobile Carbon

Mobile H & O Mobile Nitrogen Ash (acid soluble) Ash (non-soluble)

Principal Constituents of Biochar:

• Moisture (as delivered)• Ash (as delivered and from what)• Mobile Matter versus Resident Matter

• Mobile - can migrate out of the char• Resident - stays with the char & soil• Matter = Carbon and H&O portions• Carbon is measured for CO2 sequestration,

but plants care about soluble organics and plant nutrients available in the soil

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Resident Carbon Resident H & O Resident Nitrogen Mobile Carbon

Mobile H & O Mobile Nitrogen Ash (acid soluble) Ash (non-soluble)

What causes the variations in Mobile and Resident Matter?

What it was made from andthe way it was made.

Excerpt from: The Art, Science, and Technology of Charcoal Production, Antal, et.al., Ind. Eng. Chem. Res., Vol. 42, No. 8, 2003 (page 1621).

Principal Constituents of Biochar:

• Moisture (as delivered)• Ash Content (as delivered and from

what)• Mobile Matter versus Resident Matter

• Cation Exchange Capacity• ion exchange resin behavior

• Adsorption Capacity• activated carbon behavior

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Pivotal Biochar properties:

Short-term Effects• Ash Content – due to pH impact• Mobile Matter – due to stimulating soil

microbes, which complete for nitrogen

Long-term Effects• Resident Matter – because it contains the

• Cation Exchange Capacity• Adsorption Capacity

If you google the phrase “Characterizing Biochars”, you will get directed to:

http://terrapreta.bioenergylists.org/Characterizing_Biochars

Where you will find a downloadable 8 pages on:

Characterizing Biochars prior to Addition to Soils

By: Hugh McLaughlin, PhD, PEAlterna Biocarbon Inc.January 2010

Yes, not a coincidence – this Hugh McLaughlin ………….

Options for obtaining Biochar

• You can buy it – but from who?– Some charcoals are good biochars, some are

BAD – and all need to be tested

• You can make it– For “gardening”, TLUDs work best– The other approach is “Retort” processes– Equipment is coming to the market – slowly

• Example: Adam Retort – about 350 kg/batch

Whether you make your own biochar or purchase it from a supplier, it is a buyer-beware situation.

Biochar currently has the same quality controls and regulatory structure as “Snake Oil” enjoyed in the 1800’s.

Remember, biochar corrects deficiencies in existing soil-crop combinations, so the biochar has to be matched to the situation.

How does wood burn?• Wood, consists of hemicellulose, cellulose and lignin

– Hemicellulose gasifies at 250 – 300C– Cellulose splits into char and volatiles between 300C and

450C– Lignin splits into char and volatiles between 300C and

750C– Volatilization cools the remaining solid, but the gases burn

and generate radiant heat (yellow to blue light)– Eventually, oxygen can react with the remaining char to

make CO2, H2O and ash, plus more heat (red light)– Putting it all together, we have:

Theories for Ancient Practices

• Prior to steel axes, fire was the main tool for modifying the landscape and clearing land

• Staple crops tend toward starches, which require significant potassium and phosphates – which have to be added for sustained field productivity (and this field was a lot of work)

• Field preparation by transporting water vegetation, like palm leaves, then “cool burning” to release fertilizers into soil

H-1. Charcoal burners were a strange breed, living a lonely life in the forest, like wild beasts… At its best, making charcoal was not for any normal human.  The time required for charring a small mound varied from one to two weeks, but with mounds 30 feet or more round, a month was average.   During all that time, through every kind of weather, the charcoal maker lived with his mound, sleeping only in dozes for fear a flame might start and explode into a full fire which would demolish the mound.  There was no time for washing; there was seldom more shelter than a bark lean-to. 

Any Volunteers for running a Earth mound Kiln?

Earth Kiln – Ohio - 1942

Tropical Products Institute - Mark V

Tropical Products Institute - Mark V – IN ACTION

Figure 4: Completed TLUD

Google “1G Toucan”

Figure 7: Half way through burn

Figure 10: 1G Toucan Biochar

Larger than TLUDs, appropriate for home gardeners and consuming small amounts of scrap wood or “forestry slash” are:

• Two Barrel Retorts• Double Barrel Twin Keg Retorts• Jack Daniel’s Rickyard Technology

Commercial operations require larger equipment and regulatory approval:

• Adam-style Retorts• This is a developmental “Chicken or the Egg” – Nobody makes them because nobody wanted them

The Mobile Adam Retort c/o New England Biochar

BIOCHARDEMONSTRATION

This demonstration is being allowed by the Massachusetts Department of Environmental Protection for demonstration purposes only. Please be advised that the installation and operation of Biochar equipment in the Commonwealth of Massachusetts may be in noncompliance with the Massachusetts air quality regulations. If you are interested in pursuing the installation and operation of a Biochar unit in Massachusetts, please contact your local MassDEP office for guidance.

As posted at NESFI, Nov. 14, 2009, “A Biochar Demonstration Day”

Regulation of the Disposal of Wood WasteAmended by the Board of Health on November 19, 2007

“Wood Waste disposals are prohibited in the Town of Groton.”

(prohibiting the burial of wood waste refuse materials in the Town of Groton)

After the ice storm of December 2008, the Town of Groton decided to get into the wood chipping business. They enjoy an abundance of raw material and no apparent outlet……

Welcome to 151 Hill Road, Groton

Turning 180 degrees, for the view from the Front Yard

Another 90 degrees to the left, the view to the West.

Summarizing:

Recycling Biomass into Biochar permanently sequesters about one half the carbon atoms in the biomass when it dies.

Towns currently have a major biomass management challenge – with systems for collecting biomass, but not returning it to the ecosystem.

Biomass to Biochar devices are currently only permitted as “On Farm” or “Homeowner” activities – for personal use and outside commercial endeavors.

Regulatory status is “undetermined”, since practice is new to the current regulatory and environmental guidelines.

Biochar: Recycling Waste Biomassto its Highest Value Use

Hugh McLaughlin, Ph.D., P.E.

Director of Biocarbon Research

www.alternabiocarbon.com

Thank you for your attention

QUESTIONS?