Gasification and pyrolysis of poultry litter – An opportunity to produce bioenergy and

nutrient rich biochar

Natalie Taupe

Supervisors: JJ Leahy, Witold Kwapinski

Joint Scientific Workshop 2015 Erfurt, Germany

Combustion

Gasification

Liquefaction Pyrolysis

Anaerobic Digestion

Microbial Fermentation

Thermochemical conversion Biochemical conversion

Heat Gas Oil Char Biogas

Distillation Steam turbine

Fuel cell

Gas engine

Ethanol

Gas turbine Engine Boiler

Methanol Hydrocarbons Hydrogen

Upgrading

Diesel

Heat Electricity Fuels

Complete oxidation

Sub stoichiometric oxygen

No external oxygen

Ash

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Gasification and pyrolysis pack energy into chemical bonds, while combustion releases it

Biochar is obtained from the carbonisation of biomass

Intention: - Improve soil functions - Reduce greenhouse gas (GHG) emissions Poultry litter vs. plant based biochars1: - Higher ash content (liming agent) - Higher nutrient content, especially nitrogen and phosphorous - Lower carbon content - Higher cation‐exchange capacity (CEC) (Gaskin et al, 2008)

- Greater ability to adsorb and sequester metal ions (Lima et al 2009)

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1Draper, K., & Tomlinson, T. (2012)

• Strong reduction of the waste in mass (about 70–80%) and in volume (about 80– 90%)

• Reduction of greenhouse gas emissions from anaerobic decomposition of the organic wastes

• No pathogens & odour compounds

• Reduced heating fuel requirements due to excess heat from the process

• Reduced nutrient run off

• Potential for added income from selling biochar to a local market or a distributer

Advantages 4

• Consistent moisture content • Tar formation • Loss of N • Capital investment required by

the farmer

Pyrolysis/ Gasification

Disadvantages

Updraft Gasification for Recycling Poultry Litter on Farm-Scale

Objectives:

- Critical analysis of the use of updraft gasification of poultry litter

- System analysis and process performance

- Characterization of syngas, tar and char - Energy value

- Fertilizer value (NPK mass distribution)

- Other values

Updraft gasification (counter current)

Drying

Pyrolysis

Gasification

Combustion

Producer gas

Air

Fuel

Biomass H20 heat

Biomass Charcoal/tar Heat/no air

Char H2O and CO2

O2/air

CO2, H2O H2 and CO Heat/no air

CO, CO2, H2, H2O,

CH4, N2

contaminants:

- tars, particulates

- H2S, HCl, NH3, HCN, COS, alkali metals)

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Figure: Schematic of the updraft gasification system. The main input (IN) and output (OUT) flows are highlighted

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energy balance (LHV)

mass balance of the process

PL

feedstock

Requirements

for updraft*

Moisture content ar. [wt. %] 30.2 < 50

Ash content db. [wt. %] 18.2 < 15

Bulk density ar. [kg m-3] 418 > 400

Ash melting point [°C] 639 > 1000

Particle size [mm] <10 < 100

Average particle size [mm] 2.1

Particle size > 5 mm [wt.%] 9

Particle size 2.8 mm - 5 mm [wt.%] 18

Particle size 1 mm - 2.8 mm [wt.%] 36

Particle size 0.5 mm - 1 mm [wt.%] 17

Particle size 0.25 mm - 0.5 mm [wt.%] 9

Particle size < 0.25 mm [wt.%] 11

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Table: Physical and chemical properties of the PL feedstock compared to the requirements for updraft gasification fuels

*Arena et. al., 2012

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Parameter value

Gasifying medium T [°C] 0

Tbed [°C] 580-680

A/Fstoichiometric 5.30

A/Factual 0.87

ER 0.16

Cold gas efficiency (CGE) 0.26

Carbon conversion efficiency (CCE) 0.44

Table 2: Operating and performance parameters

CGE = the ratio of the chemical energy

of the produced syngas and the fuel CCE = ratio between the mass of carbon in

the product gas and the initial carbon input

from the biomass

ER = ratio of the actual fuel air ratio and

the air required for complete combustion

Basu, P. (2010). Biomass Gasification and Pyrolysis. Elsevier.c

Updraft

Continuous1

Updraft

Batch2

FBG

Batch3

FBG

Batch4

Typical

Syngas composition5

Temperature [°C] 580-680 817 700-770 800

ER 0.16 0.34 0.32 - 0.40

Ash content wt.% 12.08 44 25.1

O2 5.5

N2 56.2 40-50

CH4 1.0 0.9-1.4 2.02-2.24 2.3 3-5

CO2 19.1 3.7-11.0 19.61-21.56 20.8 10-15

CO 12.9 28.1-28.4 4.76-6.86 22.3 10-15

H2 4.2 6.1-7.3 4.61-7.17 8.5 15-20

CnHm 1.1 (Ethylene) 0.9-1.15

Heating value

[MJ m-3N]

3.53 (HHV)

3.39 (LHV)

4.3-4.6 (HHV)

2.8 (LHV)

4-6 (HHV)

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Table: Clean syngas composition [vol.%] in comparison with previous studies

1 PL updraft gasification 2 Priyadarsan et al. [14] 3 Die Gregorio et al. [9] 4 Dayananda and Sreepathi et al. [31] 5 McKendry [15]

Tar / water emulsion

pH 9.63 (4.68 for pyrolysis oil) KF water content: 89 wt.% Upgrading or combustion?

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Composition Area [wt. %]

Normal paraffins 3.7

Iso paraffins 11.4

Cyclo paraffins 24.4

Mono aromatics 0.9

Di aromatics 3.6

Poly aromatics 1.6

Organic acids 2.4

Alcohols 8.8

Aldehydes 0.2

Amides 1.9

Amines 3.4

Esters 0.5

Indenes 2.9

Ketones 3.7

Olefins 11

Phenolics 2.9

Organo nitriles 2.6

Halogen containing

organics 5.8

Oxygenates 0.8

Others 7.5

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Char from updraft gasification and slow pyrolysis Maximum temperature: 400 °C and 600 °C Heating rate: 20 °C min-1

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NPK Sample BM PL

Char

400

Char

600

Char

gasification

Proximate analysis

Moisture (wt. %) ar. 10.6 30.2 4.8 5.9 7.8

Ash (wt. %) db. 3.2 20.2 30.3 44.5 54.8

VM (wt. %) db. 88.3 75.1 47.8 18.8 26.5

FC (wt. %) db. 8.4 4.7 22.0 36.7 18.7

Heating value HHV (MJ kg-1) ar. 17.4 12.8 19.9 19.5 14.3

LHV (MJ kg-1) ar. 16.6 11.4 18.9 19.1 13.7

Bulk density (g ml-1) ar. 62 418 437 453 501

Ultimate analysis

H (wt. %) db. 5.9 5.1 4.2 1.2 2.1

C (wt. %) db. 46.8 41.7 47.2 48.5 42.4

N (wt. %) db. 0.4 4.7 5.5 4.2 4.3

S (wt. %) db. 0.0 0.8 0.7 0.6 0.9

O (wt. %) db. 43.6 29.5 13.6 3.6 8.20

Carbon sequestration

Figure: Van Krevelen diagram

Molar H/C ratio < 0.7

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Budai et al. (2013)

Biochar

Figure: Lettuce (lactuca sativa)

2 wt% biochar amended soils

Plant growth improvement by

addition of poultry litter biochar from

• Slow pyrolysis 600°C (x33)

• Slow pyrolysis 400°C (x32) • Gasification (x27)

Figure: Char gasification

Figure: Char slow pyrolysis

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NPK

Area C O Na Mg Si P S Cl K Ca Mn Total

1 40 10 0.6 1.5 3.4 5.5 39 100

2 85 7.3 0.4 0.6 0.8 0.4 5.4 100

3 42 31 1.6 1.0 0.6 2.8 0.7 2.7 13 3.8 0.2 100

4 51 25 1.7 1.3 0.2 2.6 0.6 3.9 12 2.1 0.2 100

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(a) (b)

1

(c)

1 1

(d)

Figure: SEM images of

PL char showing the

porosity and structure of

the char (a and b) and

ash particle (c and d).

Area C O Na Mg Al Si P S Cl K Ca Total

particle 17 40 0.3 0.5 0.1 0.2 1.3 0.8 0.5 3.7 36 100

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Conclusions • The process performance (0.26) is low compared to

gasifiers fed with dry plant derived fuels (~0.7) • Total solid waste reduction was 42.5 wt.%. • The clean syngas is of average quality compared to

previous studies (LHV = 3.4 MJ m-3N )

• The tar/water emulsion is of very poor quality and needs to be upgraded. A high amount of nitrogen in form of ammonia is stored in the emulsion, which probably increases the pH.

• The char has a high potential to be used as a biochar; however, further investigations on toxins, such as PAHs, are necessary.

• Arena, U. (2012). Process and technological aspects of municipal solid waste gasification. A review. Waste management (New York, N.Y.), 32(4), 625–39

• Basu, P. (2010) Biomass gasification and pyrolysis: practical design and theory. Elsevier

• Budai, A., Zimmerman, A., Cowie, A., Webber, J., Singh, B., Glaser, B., Masiello, C., Andersson, D., Shields, F., Lehmann10, J., others, 2013. Biochar Carbon Stability Test Method: An assessment of methods to determine biochar carbon stability. International Biochar Initiative.

• Dayananda, B. S., & Sreepathi, L. K. (2013). An Experimental Study on Gasification of Chicken Litter, 2(1), 63–67.

• Di Gregorio, F., Santoro, D., & Arena, U. (2014). The effect of ash composition on gasification of poultry wastes in a fluidized bed reactor. Waste Management & Research, ISWA, 32(4), 323–30.

• Draper, K., & Tomlinson, T. (2012). Poultry Litter Biochar – a US Perspective. International Biochar Initiative.

• Priyadarsan, S., Annamalai, K., Sweeten, J. M., Mukhtar, S., & Holtzapple, M. T. (2004). Fixed-bed Gasification of feedlot manure and poultry litter biomass, 47(5), 1689–1696.

References

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Acknowledgement

Financial support for this work is gratefully acknowledged from the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme FP7/2007-2013/ under REA grant agreement n° [289887].

Thank you for you attention

Any questions?

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CO