Does Biochar Deliver Carbon- Negative Energy? · Biochar Heat exhaust Fertilizers Electricity production Fossil fuels production Construction materials Shredding (a) Roberts et al,

Johannes LehmannDepartment of Crop and Soil SciencesCornell University

Does Biochar Deliver Carbon-Negative Energy?

Terra Preta de Indio©

J. M

ajor

, 200

3

“Terra Preta”‘normal’ soil

Terra Preta

‘normal’ soil

(Central Amazon, Brazil)

©B

Gla

ser

2001

500 to 8,000 years BP

The Discovery of Terra Preta

What is biochar?

Schmidt and Noak, 2000, Global BiogeochemCycles 14, 777-793

Knicker, 2007, Biogeochem 85, 91-118

Complete chemical change during heating in absence of air (pyrolysis)

Natural Occurrence

“Natural” Biochar Abundance in Soils

NSA Lead ProfilesQLD TransectDWN TransectMajor Australian CitiesKatherineDaly Waters

0

5

10

15

20

25

30

35

10203040506070 80 90100 NSA (N=58)QLD (N=114)

DWN (N=280)

N

umbe

r of s

oils

(% o

f all

test

ed s

oils

)

Black Carbon (% of total organic C)

Average≈20%(n=452)

34Gt SOC (0-1m)(Grace et al., 2006, Carbon Balance and Management 1,14)

20% ≈ 7Gt0.1Gt CE /yr fossil fuel(Department of Climate Care, 2008)

Lehmann et al, 2008, Nature Geoscience 1, 832 - 835

Biochar Abundance in World Soils

Krull et al, 2008, in: Nova Sci Publ

(World Soils Archive of ISRIC)

Biochar System – Core Principles

Lehmann, 2007, Frontiers in Ecology and the Environment 7, 381-387


Lehmann, 2009, Springer

Pyrolysis40-55%carbon

75-90%carbon

75% mass loss

50% carbon loss

BIOMASS BIOCHAR


Lehmann et al., 2010, forthcoming

H2OCO, CO2, CH4volatile organics O

O

OH

O O

O

OCH2

OH

OHOH

O OH

OH

O

OH

O+ CH3

HO

CH+

O

OH

O

OH

HOHO

OH

OHO

OOH

OH

OH

n

O

H

HH

H

OH

H OH

O

OH

O OH

H

HH

OH

H

OH

OH

OH

Cellulose, Lignin etc. Amorphous Carbon Turbostratic Carbon

O/C 0.7 0.5 0.3 0.1H/C 1.5 1.0 0.5 0.3Temperature ~200°C ~400°C ~600°C

Relative Proportion

Pyrolysis Intensity

Biochar Stability and Stabilization Mechanisms

Biochar Stability and StabilizationChemical stability + particulate nature

(a) (b)

(c) (d)

Lehmann et al, 2008, Nature Geoscience 1, 238-242Lehmann et al, 2009, in: Earthscan Publ

10 μm

Total Carbon Black Carbon

Biochar Stability and Stabilization

Saturation (Six et al, 2002, Plant and Soil 241: 155-176)

C Input

C in

Soi

l Ordinary organic matter(plant residues, manures, compost)

Biochar

Days

0 100 200 300 400 500

C m

iner

aliz

atio

n [m

g C

O2-

C g

-1 C

]

0

50

100

150

200 HAT ACUDS

Open = Adjacent soilFilled = Anthrosol

LSD=0.05

BC-poorsoils

BC-rich soils

Biochar Stability

Liang et al., 2008, Geochimica et Cosmochimica Acta72, 6096-6078

(N=3; BC age ranges from 800 to 7,000 years)

(Terra PretaCentral AmazonDefined period of BC accumulation)

Mean residence time of 4035 yrs at 10°C MAT

0 30 60 90 120 150 180

0 30 60 90 120 150 180

0

10

20

30

40

50

60

0 30 60 90 120 150 180

0

10

20

30

40

50

60

0 30 60 90 120 150 180

0

40

80

120

160

200

0 30 60 90 120 150 180

0

40

80

120

160

200

0 30 60 90 120 150 180

0

40

80

120

160

200

0

10

20

30

40

50

60

0 30 60 90 120 150 180

0

10

20

30

40

50

60(a) ME (b) NY

(c) PA-1 (d) OH

(e) TN (f) GA

(g) AL

BC-containing soilAdjacent soil

Days

Biochar StabilityBC Soils

Cheng et al., 2008, Journal of Geophysical Research, 113, G02027

Non-BC Soils

Car

bon

Dio

xide

Evo

lutio

n (m

g C

O2-

C/g

C)

Biochar from hardwood in storage areas for historical pig iron production(130 years old)

MRT of 1335 yrsat 10°C MAT

Biochar Stability

Lehmann et al, 2008, Nature Geoscience 1, 832 - 835

Time

Soi

l car

bon

(Mg

ha-1 0

.3m

-1)

0

10

20

30

40

No BC formationBC formation but no BC disappearanceBC formation with fitted BC disappearance

BC

non-BC

modelled

mea

sure

d

Inceptisols (Northern Territory, Australia)13 and 15 profiles27°C MAT, 887 mm MAPGrass vegetation under varying assumptions of burning severity and BC formationModel run to equilibrium (for BC MRT to 1m)

MRT of 1300 and 2600 yrs(718-9259) at 28°C MAT

Biochar Stability

Kuzyakov et al., 2009, Soil Biol. Biochem 41, 210-219

(ryegrass biochar, n=4)

MRT of 2000 years

Incubation period (days)

Biochar Quality, Biochar Stability

Corn-BC Oak-BC0

5

10

15

20350°C600°Ca

bb b

(1 year, 30°C, in sand culture, N=8)

Car

bon

loss

rate

(% y

ear-1

)

Nguyen and Lehmann, 2009, Organic Geochemistry 40, 846-853 Nguyen et al., 2010, Environmental Science and Technology 44, 3324–3331

A (corn-350-BC) B (corn-600-BC)

5 nm 5 nm

Biochar Decomposition

Lehmann et al., 2009, in: Earthscan Publ

Bio

char

pro

duct

ion

and

appl

icat

ion

to s

oil

Interactions with mineraland organic matter

Leaching/eluviation

Erosion

Abiotic degradation

Biotic decomposition of labile biochar fraction

Biotic decomposition of stable biochar fraction

Bio-/pedoturbation

Time

Protection by aggregation

Recalcitrance

Stab

ility

Mec

hani

sms

Dec

ay/T

rans

port

Mec

hani

sms

Biochar Decomposition

Lehmann et al., 2009, in: Earthscan Publ

Time (years)

0 20 40 60 80 100 120

Car

bon

rem

aini

ng (%

of i

nitia

l)

0

20

40

60

80

100

2307

5 years2 years

10 years 50 years

100 years1625

327

138

57

MRT2

Global Potential for Emission Reductions and Carbon Sequestration

Lehmann et al, 2010, in: Imperial College Press , forthcoming

Years0 100 200 300 400 500

Annu

al A

pplic

atio

n an

d M

iner

aliz

atio

n(fr

actio

n pe

r yea

r)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Application

100

5001000

10,000

50

200

50

105

0

20

Years0 100 200 300 400 500

Ann

ual A

pplic

atio

n an

d N

et S

eque

stra

tion

(frac

tion

per y

ear)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Application

100

500

100010,000

50

200

50

10

5

0

20

Half of total adoption within 30 years and 90% within 50 years

MRTProportion of labile C (MRT of 20 yrs)

Biochar Effects on non-CO2 Greenhouse Gases

Effects of Biochar on Nitrous Oxide

Bhupanderpal-Singh et al., 2010, JEQ published online

N2O: Up to 73% reduction

VertisolAlfisol

Biochar Soil Improvement

Organic Carbon (mg g-1)

0 10 20 30

Cat

ion

Exch

ange

Cap

acity

(mm

olc k

g-1)

0

100

200

300

r2=0.909CEC=2.81C+9.1

r2=0.784CEC=8.60C-18.6

Anthrosols

Adjacent Soils

DSACULGHAT

Other Anthrosols (Sombroek et al., 1993)

Biochar-rich soils

Biochar-poor soils

Liang et al., 2006, Soil Sci. Soc. Am. J. 70: 1719-1730

Biochar Soil Improvement

Biochar Product

Lehmann, 2007, Frontiers in Ecology and the Environment 7, 381-387

Temperature (°C)0 200 400 600 800 1000

Car

bon

reco

very

(% o

f ini

tial C

)

50

60

70

80

90

100

110

pH

2

4

6

8

10

12

14

CE

C (m

mol

c kg-1

)Su

rface

are

a (m

2 g-1

)

0

50

100

150

200

250

300

350Carbonrecovery

pH

Opt

imum

CEC

Surface area

Biochar from black locust(N=3)

Biochar Oxidation

Cheng, Lehmann, Engelhard, 2008, GeochimCosmochim Acta, 72, 1598-1610

2 3 4 5 6 7 8 9 10 11

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10 11

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10

0

500

1000

1500

2000

2500

2 3 4 5 6 7 8 9 10

0

500

1000

1500

2000

2500

2 3 4 5 6 7 8 9 10

0

500

1000

1500

2000

2500

pH

Surf

ace

char

ge (m

mol

e kg

C-1

)

New-BCHF

BC30

BC70 QC

NY

BC-HA

New-BCGW

CT

Negative chargePositive charge

Point of zeronet charge(PZNC)

>2000

<20 >7

<3

130-year-old Biochar(from pig iron production) in comparison to biochar made with traditional kilns

Nutrient Retention Ca

Nut

rient

am

ount

(kg

ha-1

)

-60

-40

-20

0

20

40

60 Crop uptake Leaching by saturated flow Leaching by unsaturated flow

Mg

-40

-20

0

20

40

K

Biochar application rate (t ha-1)

0 20-50

0

50

100

150

200

250

300NO3 + NH4*

Biochar application rate (t ha-1)

0 20

-100-50

050

100150200250300350

Major, PhD thesis

Biochar applied onceTotal over 2 yearsColombia (n=3)a b

ab

a b

ab

B

A

B A

BA

AA Improved nutrient

uptake and crop yield

Temporal Variation in Yield Response

Major et al., 2010, Plant and Soil, published online

Year

2003 2004 2005 2006

Mai

ze g

rain

yie

ld (t

*ha-1

)

0

2

4

6

8

10Control8 t * ha-1 20 t * ha-1

y

Year

2003 2004 2005 2006

Mai

ze g

rain

yie

ld (t

*ha-1

)

0

2

4

6

8

10Control8 t * ha-1 20 t * ha-1

y

Applied once in 2003Colombian Llanos(N=3)

a

b

c

a

ab

b

a

a

baaa

No biochar8t/ha biochar

20t/ha biochar

Time since conversion (years)

0 20 40 60 80 100 120

Mai

ze g

rain

yie

ld (t

ha-1

)

2

4

6

8

10

12BiocharSawdust Manure Tithonia

LSD0.05

Soil Fertility Benefits Dependent on Soil Properties

Kimetu et al., 2008, Ecosystems 11: 726-739

Biochar applied each seasonKenya (n=3)

Soil Biology

© Ogawa

Biochar System – Core Principle

Lehmann and Joseph, 2009, Earthscan

WasteManagement

EnergyProduction

SoilImprovement

Mitigation ofClimate Change

Social, Financial Benefits

Biochar System

Lehmann, 2007, Nature 447: 143-144

Systems Analysis: Energy Balance

6.99.1Corn stover (crop residue)

6.99.0Wheat straw

5.37.0Switchgrass

2.33.0Forage corn

Biochar to soil

Biochar to energy

Energy balance (MJ/MJ), Slow pyrolysis

Gaunt and Lehmann, 2008, Environmental Science and Technology 42: 4152-4158

Systems Analysis: Emission Balance

Gaunt and Lehmann, 2008, Environmental Science and Technology 42: 4152-4158

12,551-18,5954083-7710Bioenergy crops

9575-11,8332002-3736Crop residues

Biochar to soilBiochar to energy

Avoided Emissions (kg CO2/ha/yr), Slow pyrolysis

Biomass collection Drying Slow pyrolysis

Pyrolysis facility

TT Soil

application

Natural gas production & combustion

(-)

(-)

Farm equipment, agrochemicals

T

T

T

Compost

(-)

T

Syngas heat

product

BiocharHeat exhaust

Fertilizers

Electricity production

Fossil fuels production

Construction materials

ShreddingBiomass collection Drying Slow pyrolysis

Pyrolysis facility

TT Soil

application


(-)

(-)


T

T

T

Compost

(-)

T

Syngas heat

product

BiocharHeat exhaust

Fertilizers




Shredding

(a)

Biomass collection Drying Slow pyrolysis

Pyrolysis facility

TT Soil

application


(-)

(-)


T

T

T

Compost

(-)

T

Syngas heat

product

BiocharHeat exhaust

Fertilizers




ShreddingBiomass collection Drying Slow pyrolysis

Pyrolysis facility

TT Soil

application


(-)

(-)


T

T

T

Compost

(-)

T

Syngas heat

product

BiocharHeat exhaust

Fertilizers




Shredding

(a)

Roberts et al, 2010, Environmental Science and Technology 44, 827–833

System boundaries

Systems Analysis: Life Cycle Assessment


Systems Analysis: Life Cycle Assessment

0 300 600 900

emit.

reduct.

emit.

reduct.

emit.

reduct.

emit.

reduct.

emit.

reduct.

Greenhouse gases (kg CO2e t-1 dry feedstock)

LUC & fieldemiss.agrochems

field ops

other

stable C

avoid foss fuelgen. & comb.land-use seq.

reduced soilN2O emiss.avoid compost

Late

st

over

Ear

ly

stov

erS

witc

h gr

ass

BYa

rd

was

te

Net = - 864

Net = - 793

Net = - 442

Net = + 36

Net = - 885

Sw

itch

gras

s A

(b)0 300 600 900

emit.

reduct.

emit.

reduct.

emit.

reduct.

emit.

reduct.

emit.

reduct.

Greenhouse gases (kg CO2e t-1 dry feedstock)

LUC & fieldemiss.agrochems

field ops

other

stable C

avoid foss fuelgen. & comb.land-use seq.

reduced soilN2O emiss.avoid compost

Late

st

over

Ear

ly

stov

erS

witc

h gr

ass

BYa

rd

was

te

Net = - 864

Net = - 793

Net = - 442

Net = + 36

Net = - 885

Sw

itch

gras

s A

(b)

Systems Analysis: Sensitivity Analysis

Late Stover Slow pyrolysis(1-10t/hr)

Stover collection energy sensitivity Energy per tonne

collected (MJ) 723 765 (baseline) 833

Net energy (MJ) 4165 4116 4036 % change 1% 0% -2%

Stover collection emissions sensitivity

Emissions per tonne collected (kg

CO2e) -33 58 (baseline) 76

Net CO2e (kg) -970 -864 -843 % change 12% 0% -2%





Char yield sensitivity

Char yield input 12 wt % 28.8 wt % (baseline) 35 wt %

Net CO2e (kg) -756 -864 -875 % change -13% 0% 1%

Stable C sensitivity Stable C content of

biochar 0% 50% 80% (baseline) 90%

Net CO2e (kg) -275 -643 -864 -938% change -68% -26% 0% 9%




Syngas energy sensitivity

Energy yield input 50% of baseline (baseline) 150% of

baseline Net energy (MJ) 1509 4116 6722

% change -63% 0% 63% Net CO2e (kg) -703 -864 -1025

% change -19% 0% 19%

Distance (km)

0 200 400 600 800 1000

Net

GH

G (k

g C

O2e

t-1 d

ry s

tove

r)

-1000

-800

-600

-400

-200

0

Net

ene

rgy

(MJ

t-1 d

ry s

tove

r)

0

1000

2000

3000

4000

5000

6000

Rev

enue

($ t-1

dry

sto

ver)

-90

-60

-30

0

30

60

Net energy

Net revenue

Net GHG

(b)

Distance (km)

0 200 400 600 800 1000

Net

GH

G (k

g C

O2e

t-1 d

ry s

tove

r)

-1000

-800

-600

-400

-200

0

Net

ene

rgy

(MJ

t-1 d

ry s

tove

r)

0

1000

2000

3000

4000

5000

6000

Rev

enue

($ t-1

dry

sto

ver)

-90

-60

-30

0

30

60

Net energy

Net revenue

Net GHG

(b)

Costs - transportation

Late stover, high C priceSlow pyrolysis(1-10 tons/hr capacity)


Co-Benefits: Waste Stream ManagementCase Study West-Virginia

West Virginia Poultry Farm

99,000 chickens125-600 t/yr poultry litter

Pyrolysis of 300 kg/hr dry litter(at 500°C) Off-sets 114,000L propane gasUS$66,000 /yr

25-120 t/yr biochar

Biochar Cook Stoves

Torres

Small-scale Bioenergy

Whitman and Lehmann, 2009, Environmental Science and Policy 12, 1024-1027

Traditional 3‐Stone Stove Biochar Cook Stove

Co-Benefits: HealthLower indoor pollution=lower respiratory

+ eye infections

Torres

Costs – Carbon Trading AspectsParaguay

Relatively easy countingProof of source possibleLow risk of rapid evasion

EnergyProduction

SoilImprovement



Biochar Benefits – Systems Dimension

WasteManagement

EnergyProduction

SoilImprovement




WasteManagement

EnergyProduction

SoilImprovement




WasteManagement

EnergyProduction

SoilImprovement




WasteManagement

Biochar – The Way Forward

Not “WHETHER”, but “WHERE”

Documents

Does Biochar Deliver Carbon- Negative Energy? · Biochar Heat exhaust Fertilizers Electricity production Fossil fuels production Construction materials Shredding (a) Roberts et al,