Challenges in Global Warming: Reduced emissions and
sequestration
Woodrow W. Clark II, Milken Institute, and Ray Chrisman, Atodyne Technologies and Affiliate Faculty,
Forest Resources, UW
Energy production from non‐fossil sources should reduce CO2
emissions
Solar and wind energy based sources are very interesting. However, there are concerns since these are very discontinuous sources.
However, proponents point out that the wind is always blowing somewhere
Building scale wind turbines, generate 1.2kwh at a price of $6,500
Sequestration side of the CO2 issue
Stabilizing CO2 at 400 ppm requires approximately 35 GT CO2 (~10 GT carbon) to be withdrawn from the atmosphere by 2030
The question is how can it be done and where can we put it? In the water or on the land?
Annual carbon fluxes
What is AgricharTM biochar?• AgricharTM product is
derived from Slow Pyrolysis which involves heating biomass in the absence (or reduced supply) of air
• AgricharTM product delivers significant agricultural and environmental benefits –whilst sequestering carbon in soil
How Char can helpOrganics to Land Vs Char
Lehmann et al., 2006, Mitigation and Adaptation Strategies for Global Change, in press
Biochar a Gigaton response
Source: Lehmann, 2007, Nature
-20
-15
-10
-5
0
5
10
Gt C
arbo
n
Annual potential for biochar sequestration
Hypothetical(40% biomass to biochar)
High
Low
Gaunt unpublished
Terra‐Preta: Evidence of longevity
• 500‐7000 years old
• Amazon ‐ Extreme
environment for fast
organics turnover
• 10% Total Carbon, 35% of which is Black Carbon. Char ≈ 3.5% of total soil.
Photos: Julie Major, Cornell University
The ‘terra preta’ example of product performance
Bulk composition of a typical biomass material
Almost any time biomass is burned both pyrolysis and
oxidation occurs
Often both processes occur such that oxidation (burning) is on the outside and provides the heat
for pyrolysis which is going on inside. The biochar that first forms is then burned when
oxygen can finally reach it.
For example, the burning of wood or cigarettes
How do we get just biochar?
The pyrolysis processes typically produce three general product types based on physical state
• A gas that includes syn‐gas (H2 and CO)
• A complex hydrocarbon liquid (bio‐oil) and water
• A solid char (primary and secondary) and ash
The relative yields and composition of these products are a function of process conditions and starting materials.
What is Agrichar TM biochar?
• AgricharTM product is derived from Slow Pyrolysis and is a primary char which means it maintains much of its original physical structure.
• This structure seems to support enhanced microbial growth, aid in water retention and enhanced soil structure.
• The material has good CEC and has a long lifetime in the soil.
• The material has no odor and low residuals.
IBI conference 9/08
BEST’s Australian Demo facility
• Fully continuous with Integrated drying
• Handles biomass with up to 50% moisture
• Can process high and low ash biomass
• Syngas produced runs 300 kWe internal combustion engine
• Approx. 35% yield by weight
• Can be scaled to process 48 & 96 dry ton/day
IBI conference 9/08
Increased Productivity
3a: Soil + Char
70 cm
2a: Soil + NPK
55 cm
4a: Soil + NPK Char
105 cm
1a: Soil only
30 cm
Summary of potential benefits of biochar
•Sequester Carbon Dioxide•Generate energy•Solve some waste management
issues like disposal of manure
•Improve soil quality
Two scenarios for energy policy in the near term
Cap and trade• Prices will go up• New technology has high
startup cost• Price may be somewhat
more stable as new forms of energy appear.
• Provides support for new processes though maybe not cost effective ones
• Some money will be spent on carbon capture
• Money stays in the system
Supply/demand balances• Prices will go up
• Supply of cheap oil has peaked
• Prices will tend to spike
• Spikes will make new technology difficult to maintain
• Support for more energy efficient processes
• Money flows out of the system
What is the impact on process technology?
More biobased processes?More new products introduced?More efficient processes?
More online analysis?More process intensification?More microreactors?More focus on process separations?