A Hybrid Pyrolytic-Electrochemical Approach for …mifbi.org/wp-content/uploads/2017/03/Innovation-Saffron-for-post.pdfA Hybrid Pyrolytic-Electrochemical Approach for Creating Fuels

A Hybrid Pyrolytic-Electrochemical Approach for Creating Fuels from Forest Biomass

Christopher M. Saffron Associate Professor

Department of Biosystems and Agricultural Engineering

Michigan Forest Bioeconomy Conference

February 2nd, 2017 Grand Rapids, MI

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Overview of Thermochemical Conversion Technologies

Increasing Temperature

200°C 400°C 600°C 800°C 1000°C

Torrefaction Fast pyrolysis

Slow pyrolysis*

Gasification (partial oxidation)

Greater than 1,000°C = combustion

Product gases is rich in CO, H2, and light hydrocarbons

Many gasifier configurations have been explored

†http://www.ecn.nl *http://www.biochar-international.org/

†

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Biomass Conversion to Hydrocarbon Fuels Rationale for displacing petroleum •  Minimize climate change impact •  Promote energy independence and security •  Slow resource depletion

~285 billion gal/yr in the U.S. alone

Rationale for pyrolysis/upgrading • First generation biodiesel and ethanol

can provide short-term remedies but have significant challenges

•  Industry desires “drop-in” hydrocarbon replacements for petroleum fuels

• Unbeatable energy to weight ratio

• Nature’s choice for energy storage

http://www.heavyequipment.com/heavy-equipment/lumber-forestry

4 Perlack RD and Stokes BJ The U.S. Department of Energy (2011) U.S. Billion-ton Update: Biomass Supply for a Bioenergy and Bioproducts Industry.

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Comparison of Scale: Fossil Energy vs. Bioenergy •  Oil: 2012 U.S. consumption about 6.8 billion bbl/yr or 1 billion tons/yr

–  C content in “CH2” is 12/14 or 86% → 860 MM tons C/yr –  E content: HHV = 45 MJ/kg → 41 EJ/year

•  Biomass: 2030 U.S. biomass 1.3 x 109 tons/yr (crop residues, forest wastes, and energy crops)

–  C content in “CHOH” is 12/30 or 40% → 520 MM tons C/yr –  E content: HHV = 15 MJ/kg → 18 EJ/year (assuming perfect conversions)

•  Today’s biofuels: Consider ethanol production: –  C6H12O6 → 2CH3CH2OH (MW = 46) + 2CO2 (MW = 44) –  Concentrates plant-captured E into half the mass, but throws away 1/3 of

the C –  E content: Ethanol doesn’t come close to a 1:1 gasoline or diesel

replacement

•  Carbon Efficient Bioenergy Systems Needed! •  Energy Upgrading Strategies for Bioenergy Systems Needed!

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Bioenergy System Diagram using Decentralized Depots

Cultivation Harvest Haul Collection

On-site Storage Grind & Dry Fast Pyrolysis &

Condensation

Transport On-site Storage

CentralizedConversion Transport Retail End

Use

CO2 H2O Fertilizers

Solar Energy

CO2, H2O, Shaft Work, Heat Loss

Biomass Upgrading Depot

Utilities, Reagents, Catalysts

Electro-catalysis

Non-carbon Emitting Electricity

Renewable Hydrogen

•  Biomass Upgrading Depots (BUDs) are small-scale facilities used to preprocess biomass to improve its physicochemical properties

Biochar backhaul

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Biomass Fast Pyrolysis

Biomass Bio-oil + Char + Gases (100%) = (up to 70%) + (~15%) + (~15%)

•  Pyrolysis is thermal decomposition without oxygen –  Low energy requirement: Nearly neutral endo- vs. exothermicity –  Modest temperatures: Pyrolysis reaction temps. of ca. 500°C –  Rapid throughput: Short vapor residence time in the reactor (<1s) –  Carbon-retentive: Cellulose, hemicellulose and lignin are liquefied –  Densification: Bio-oil specific gravity is 1.1-1.2

→

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Pyrolysis Reactor

Condenser and collection vessels

Biomass feeder and reactor

Electrostatic precipitator

Gas flame calorimeter

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Biomass Fast Pyrolysis

Biomass → Bio-oil + Char + Gases (100%) = (up to 70%) + (~15%) + (~15%)

•  Pyrolysis is thermal decomposition without oxygen –  Low energy requirement: Nearly neutral endo- vs. exothermicity –  Modest temperatures: Pyrolysis reaction temps. of ca. 500°C –  Rapid throughput: Short vapor residence time in the reactor (<1s) –  Carbon-retentive: Cellulose, hemicellulose and lignin are liquefied –  Densification: Bio-oil specific gravity is 1.1-1.2

•  Bio-oil unwanted properties (stabilization): –  Reactive and unstable: aldehydes, ketones, phenols –  Corrosive: carboxylic acids, phenols –  Low specific energy: HHV is 15 to 19 MJ/kg

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Bio-oil Reactivity and Instability

Adapted from: Diebold J.P., et al. Review. 1999.

H HO

Bakelite resin

Electrocatalytic Hydrogenation and Deoxygenation

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We,in

Divided batch “H-cell”

Ruthenium on activated carbon cloth catalytic cathode

Nafion membrane

Platinum anode

Upgrading to Improve Energy Content

12 12 Increase in Energy Content

28 30 32 34 36 38 40 42 44 46 48

Guaiacol Phenol Cyclohexanol Cyclohexene Cyclohexane

Hig

her H

eatin

g Va

lue

(MJ/

Kg)

Gasoline Level Bio-oil Model

Compound

Model Monomer Studies using Ru/ACC

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OOH

0.2 M HCl 100 mA 6 hrs @ 80 °CRu/ACC

OHO

+

OHGuaiacol

O

OHO

0.2 M HCl 100 mA 6 hrs @ 80 °CRu/ACC

OHO

+

OH

+

OHO

O

OOOH

Syringaldehyde

0.2 M HCl 100 mA 6 hrs @ 80 °CRu/ACC

OHOO

+

OHO

+

OH

OHEugenol

OH OH0.2 M HCl 100 mA 6 hrs @ 80 °C

Ru/ACC +O

OH

+O O

Vanillin

Raw Bio-Oil

200 mA ECH for

6 hrs

350 mA ECH for

6 hrs

Electrocatalytic Hydrogenation of Raw Bio-oil

•  pH increase of 1 was found for both the anode solution and bio-oil at 200 mA

•  Volume of anode solution changed from 30mL to 25mL

•  Volume of the bio-oil remained essentially the same (30mL to 29.5mL)

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Concentric tube design

Lam, Chun Ho. “Electrocatalytic Upgrading of Biomass Pyrolysis Oils to Chemical and Fuel.” PhD dissertation, Michigan State University. 2014.

Solid polymer electrolyte reactor

An, W.D., J.K. Hong, P.N. Pintauro, K. Warner, and W. Neff, The electrochemical hydrogenation of edible oils in a solid polymer electrolyte reactor. I. Reactor design and operation. Journal of the American Oil Chemists Society, 1998. 75(8): p. 917-925.

Electrocatalysis Cell Configurations

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Upgrade using Renewable Energy

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Upgrade using Renewable Energy

Pyrolysis conditions: T = 400-600 ºC P = 1 atm

Electrocatalysis conditions: T = 50-99 ºC P = 1 atm V = variable; currently 1-10 Volts in H-cells 5-10x less in flow cells H2 production must be controlled

Hydroprocessing conditions: More severe--up to 2,000

psig H2 Can be managed in large, centralized refineries

100 tons/day 100 MMGal/yr

Minimum Bio-Oil Selling Price (MBOSP)

Minimum Fuel Selling Price (MFSP)

Electrocatalysis:

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In Summary

1.  Fast pyrolysis increases the bulk density of biomass

2.  Electrocatalysis creates a stable intermediate with high energy density

3.  Local wind and solar energy used upgrade biomass’ energy content

4.  Pyrolysis and electrocatalysis are simple and performed at safe P

5.  Biochar has economic and environmental benefits

6.  Pyrolysis and electrocatalysis provides a carbon efficient pathway that increases the amount of energy available as finished fuel

7.  Improves growers’ participation in the financial upside, depots will require trained professionals and a professional wage, and the revenue gained will increase the tax base

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Acknowledgements

•  Key faculty members: Dr. Ned Jackson, Dr. Dennis Miller

•  Other group members: Dr. Shantanu Kelkar, Dr. Zhenglong Li, Dr. Chun Ho Lam, Dr. Li Chai, Dr. Peyman Fasahati, Dr. Ryan Stoklosa, Dr. Mikhail Redko, Dr. Edmund Okoroigwe, Mr. Jon Bovee, Dr. Lars Peereboom, Mr. Souful Bhatia, Dr. Somnath Bhattacharjee, Mrs. Nichole Erickson, Dr. Leonardo Sousa, Mr. Cale Hyzer, Mr. Tom Stuecken, Mrs. Mahlet Garedew, Mrs. Rachael Sak, Mr. Zhongyu Zhang, Mr. Sabyasachi Das, Mrs. Tammy Lin, Mr. Zach Carter, Mr. Pengchao Hao

MTRAC

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Thank you! Questions?

Finelygroundbiomass

Screw-conveyorPyrolysisreactor

Gas

Char

Bio-oil Electrocataly=cHydrogena=on

(ECH)

GasolineDieselJetfuel

Centralrefinery

ECH

Deoxygena=on

Stabilization

Regional biomass processing depots