Distributed Fast Pyrolysis for Conversion of Biomass to Stable Refinable Crude Bio‐oils

Charles A. MullenAkwasi A. Boateng

The Science and Engineering for a Biobased Industry

Wyndmoor, PA

August 3, 2010

Biomass Conversion Pathways

Soil Amendment/Solid Fuel

F-T LiquidsH2

SYNGASH2 + CO

Biomass Pyrolysis Bio-oil

Bio-charLiquid Fuels/Chemicals

Sugars

Lignin

EthanolBiochemicalConversion

ThermochemicalConversion

Fermentation

Pyrolysis• Defined as the heating of organic material in the absence of 

air• Biomass Pyrolysis Produces Bio‐oil, Bio‐char, and Syngas

• Slow Pyrolysis– Slow Heating Rates– Temperatures 300 – 500 °C – Maximizes Bio‐char Production

• Fast pyrolysis – High heating (& cooling) Rates– Temperatures 450 – 500 °C– Maximizes Bio‐oil Production

Fast Pyrolysis at ERRC: CRIS ‐082Goals

• Bring fast pyrolysis closer to commercialization

• In‐situ stabilization for predictable product

• In‐situ upgrading to reduce downstream upgrading, amenable to existing refineries – “drop‐in” 

• Make the bio‐char a soil‐amendable product

Advantages of Fast Pyrolysis

• Amenable to small scale• On‐Farm Scale Advantage• Energy density• Less energy intensive• Relatively simpler system design• Oxygenated liquid bio‐crude 

– up‐gradable to drop in diesel, gasoine and jet‐fuels

• Infrastructure exists for its refining• Charcoal vision

– Carbon Sequestration

Vision for Distributed Processing

Carbon Cycle for Fast PyrolysisSoy Straw Example

B

Major Barriers to Commercialization of Bio‐oil as 2nd Generation Bio‐fuel

High O‐Content High Water Content Acidity: pH ~ 2.5 (corrosive)  Stability: Unstable – Over time, oligimerization and 

condensation reactions increase average MW, viscosity, and water content

Storage & Piping Problems Heterogeneity makes it unsuitable for diesel engines “as 

is” Needs stabilization, upgrading before use in existing 

refineries

• Quantify the effect of various agricultural feedstockson the pyrolysis process efficiency, kinetics, product yield and composition. 

• Develop commercially preferred catalytic and non‐catalytic processes for distributed on‐farm scale production of stable and easily upgradable bio‐oil

• Technologies for in‐situ or ex‐situ activation of bio‐char to produce  a soil‐amendment grade product

Fast Pyrolysis at ERRC: CRIS ‐082Research Objectives

Fluidized Bed Pyrolysis System

Pyrolysis Conditions

Biomass Agricultural Feedstocks

Fluidized‐Bed Material Silica Sand

Particle Size (Bed Material) ‐20 +25 mesh

Fluidizing Gas N2

Gas Flow Rate 1.0 – 1.5 kg/hr

Min. Fluidization Velocity  0.23 m/s

Superficial Velocity 0.65 m/s

Biomass Feed Rate 1.5‐3.5 kg/h

Biomass:N2 Ratio 0.46

Feed Mean Particle Size ~2 mm

Bed Pressure 4 kPa

Bed Temperature  480 – 505 °CCondenser #1 Temperature  200‐245 °CCondenser #4 Temperature 45‐65 °CESP Temperature 25‐45 °CHeat Rate ~4500 °C/sTotal Quench Rate 50‐60 ‐°C/s

Fast Pyrolysis Product Yields

0

10

20

30

40

50

60

70

80%

Yie

ld

Bio-oil Charcoal Non-Condensable Gas

Woods Grasses LegumesAg. and BiofuelsCoproducts

Carbon Conversion

0

10

20

30

40

50

60

70

80

90

% F

eeds

otck

Car

bon

Bio-oil Charcoal Non-Condensable Gas

Woods Grasses LegumesAg. and BiofuelsCoproducts

ARSOak

Chicken Litter Guayule

Barley Straw

Corn Stover

Rye-grass

Switch-grass

Alfalfastems

Soybean straw

ESP Fraction % Water  8.2 9.8 1.7 6.6 5.9 8.2 6.2 8.2 8.9Condenser Fraction % Water 29.0 30.0 N/A 35.6 15.5 33.5 23.0 42.8 31.8Total % Water  22.3 20.1 1.7 26.7 9.2 21.3 15.8 28.6 21.4Organic C:O Ratio 1.46:1 2.53:1 3.27:1 1.16:1 1.49:1 1.0:1 1.35:1 1.82:1 1.15:1HHV (MJ/kg), wet 17.9 25.3 30.4 19.3 19.5 20.3 19.9 23.7 20.9HHV (MJ/lkg), dry 23.0 31.6 30.9 26.3 26.2 25.7 23.6 33.1 25.6

pH 2.6 6.9 ‐‐ 2.4 2.9 2.8 3.1 2.9

Bio‐oil Analysis

ARS Oak

Chicken Litter

Guayule Bagasse

Barley Straw

Corn Stover

Ryegrass

Switchgrass

Alfalfa Stems

1H NMR of Bio‐oils

Woods

AnnualGrasses

Perennial Grass

Legume

400 MHz,Acetone-d6

Mullen, C. A., Strahan, G. D., Boateng, A. A. Energy Fuels, 2009, 23, 2707.

13C NMR of Bio‐oils

Mullen, C. A., Strahan, G. D., Boateng, A. A. Energy Fuels, 2009, 23, 2707.

ARS Oak

Chicken Litter

Guayule

Barley Straw

Corn Stover

Rye-grass

Switch-grass

Alfalfa

Woods

AnnualGrasses

Perennial Grass

Legume

100 MHz,Acetone-d6

Some Bio‐oil ComponentsGC/MS & HPLC

Compounds(wt%)

ARSOak

Chicken Litter Guayule Barley

StrawCorn

StoverSwitch-grass

Alfalfa Stems

Soybean Straw

Acetic Acid 11.1 0.70 3.09 8.56 6.26 2.94 3.49 5.74

Furfural ‐‐ ‐‐ ‐‐ 0.39 0.71 0.62 ‐‐ 0.56

Hydroxyacet‐aldehyde  1.3 ‐‐ ‐‐ ‐‐ 4.00 2.40 ‐‐ 0.82

Acetol 4.95 0.05 0.73 6.31 7.08 0.78 0.78 9.56

Levoglucosan 3.00 0.23 1.37 2.06 12.36 6.38 0.14 7.75

Guaiacol 0.25 0.35 0.39 0.25 0.25 0.51 0.46 0.45

Syringol 0.47 0.20 0.73 0.38 0.38 0.37 0.43 0.41

Phenol 0.12 0.44 0.65 0.30 0.30 1.14 0.95 0.16

O

O

H

HO

O

OH

OCH3

OH

OCH3

OCH3

Bio‐oil Stability

• Aging accelerated by storing bio‐oils at 90 °C for 8h and 24h

Bio‐oil Stability: Mw

Mw

300

350

400

450

500

550

600

650

0 4 8 12 16 20 24

Time at 90 C (h)

MW

Oak Barley Straw Corn Stover Ryegrass Switchgrass Soy Straw

Economic Analysis: 200 TPD plant

Feedstock43%

Utilities including Make Up

water9%

Labor,Supplies

and Overhead

22%

Depreciation26%

Bio-oil Production Costs

Operating Costs ($/ Barrel Bio‐oil)

Feedstock $13.686Utilities including Make Up water $2.941

Labor, Supplies and Overheads $7.172

Depreciation $8.384

CoProduct Credits ‐$0.832

Cost per 42 Gallon Barrel $31.351

Cost per Equivalent Barrel of Oil  $52.25

( Energy Basis)

Bio‐oil Upgrading

• Ex‐Situ upgrading is required to remove oxygen from bio‐oil to produce hydrocarbons– Hydroprocessing

– Catalytic Cracking

– Steam Reforming

• In‐Situ Upgrading (Catalytic Pyrolysis) can be used to produce stable partially deoxygenated bio‐oils and make further upgrading more facile

Catalytic Pyrolysis of Lignin(py‐GC/MS)

No Catalyst

with HZSM-5

AromaticHydrocarbon

Mechanisms of In Situ Catalytic Cracking

HO

R'

RO

R'

O

L

L

OH

R, R' = H: H/G LigninR = H, R' = OMe: G/S LigninR, R' = OMe: S LigninL = Additional Lignin Units

HO

R

R'Guaiacols

andSyringols

Depolymerization

Depolyermization+ Demethoxylation

HO

SimplePhenols

+ MeOH

+ O

R'

O

L

L

Lignin Oligomers

HZSM-5

Catalyst Deactivation

HZSM-5

Olefins

Aromatics

HZSM-5FurtherDepolyermization

HO

R

R'Guaiacols

andSyringols

Aromatics

OlefinsHO

SimplePhenols

DemethoxylationMeOH +

HZSM-5

Catalyst Deactivation

1° PyrolysisReactions

1° PyrolysisReactions

+ CO

HZSM-5

HZSM-5

HZSM-5

Carbohydrates

Lignin

Execution Plan

ElectricityProduction

Fuel OilSubstitution

Transport Fuels(Gasoline, Jet

Diesel)

Chemicals

Process

Feedstock

Ex-Situ(HYDROTREATING)

Ex-Situ(HYDROTREATING)

In-Situ Catalysis(VAPOR)

In-Situ Catalysis(VAPOR)

In-Situ Catalysis(BED)

In-Situ Catalysis(BED)

BIOMASSBIOMASS

CatalyticPyrolysis

Partial Stabilization/

DeoxygenationNon-

CatalyticPyrolysis

Full Stabilization/

Deoxygenation

Bio‐oilStabilization

DROP-IN3 Years to complete

R&D

ContingencyAvailable

Today

Green Jet-range Paraffins(Bio-SPK)

Selective Cracking/

Isomerization

Natural Oils and

FatsDeoxygenation

Renewable Jet Fuel

Solid Biomass

Catalytic Stabilization/

DeoxygenationPyrolysis

Jet Range Cyclic

Hydrocarbons

2nd Generation Renewable Jet Fuel from Oils and Biomass

The Future: 100% Renewable Jet 

The hydroplane ran on 98% Bio-SPK and 2% renewable aromatics

Jet A1Spec

Starting SPK

Woody Pyrolysis Oil Aromatics

Freeze Point (oC) -47 -63 -53Flash Point (oC) 39 42 52Density (g/mL) 0.775 0.753 0.863

Bio‐char Co‐product

• Energy Value: only $25/ton based on coal selling price of $1.10/Gj

• In light that world’s soils hold more organic C than that held by the atmosphere as CO2& vegetation; the land is a major factor in C‐sequestration

• As the earth is stressed to produce more food, fiber & energy more C is removed from ground & emitted to atmosphere

• Impacts soil’s fertility and threatens its long‐term effectiveness.

• Biochar is one solution to slow down and even reverse the process  ‐ UNCCD, Poznan, 2008

Terra Preta/Chernozems Oxisol

Glaser et al. (2001) Naturwissenschaften, 88:37–41

Fast Pyrolysis bio‐chars and Steam Activation 

Corn Stover Biochar Carbon

Bio‐char Advantages

• Bulk Density

• Enhances plant available water in sandy soils and aeration in clay soils 

• Enhances soil fertility

• Absorbs organic & inorganic pollutants (cationexchange)

• Increases crop yield

• Sequesters carbon (half life ~ 1000 yr) 

Bio‐carbon Metal Adsorption1 mM aqueous solutions

Cu2+

Broiler LitterSwitchgrassAlfalfa

Corn cob carbonCorn stover carbon

Corn Stover Bio-charCorn Cob Bio-char

Soybean straw

Cd2+ Ni2+ Zn2+% Adsorption

79.746.882.978.298.154.580.395.7

84.816.521.16.8

90.522.6

31.121.0

96.4-

19.7

95.812.3

29.230.0

13.4

39.521.036.112.595.321.337.227.8

PUR RF 51.0 15.229.217.1

Thank You

CRIS-082 CRADA Partners