Project Engineers:Federico Berruti

Matt KlaasSara Rohani

Project Supervisor: Dr. Barghi

Bio-Oil Production from Dry Distiller’s Grain in a Bubbling Fluidized Bed Reactor

497 Final Presentation

March 19, 2009

Department of Chemical & Biochemical Engineering, The University of Western Ontario, London Ontario, CANADA

Outline

OUTLINE | 02

• Motivation & The Need

• Plant Location and Capacity

• Introduction to Biomass, Bio-Oil & Pyrolysis

• Process Flowsheets

• Detailed Unit Designs

• Process Safety

• Economics

• Conclusion & Recommendations

• Acknowledgements

Motivation & The Need

MOTIVATION | 03

• Global Warming

• Depleting Conventional Fossil Fuel Reserves

• Volatile Conventional Oil Prices

• Global demand for alternative sources of renewable carbon dioxide neutral energy and for green chemicals.

• Demand for increased utilization of agricultural by-products & waste.

• Demand for reduced emissions from agricultural practices (e.g. rice-straw and flax straw combustion).

Motivation Continued

Raw Materials

Energy

Chemical Operation/Process

Products

WASTE

Green Process

Energy

Useful Chemicals

$$$

MOTIVATION | 04

One Possible Solution

SOLUTION | 05

• Conversion of Agricultural Crops, Waste & other Biomass sources into Bio-Oil via Intermediate or Fast Pyrolysis.

Plant Location & Capacity

PLANT PROPOSAL | 06

• Process 200,000 kg/day of DDG

•30,000 tonnes Bio-Oil annually

• Locate in Sarnia, Ontario

• Partner with Northern Ethanol, Inc. (DDG Supply)

• Located in Sarnia, transportation costs minimum.

• Desire elimination of DDG by-product, since

market saturated.

Introduction: Biomass

BIOMASS INTRO | 07

• Composite material made up of oxygen-containing components

• Renewable & carbon dioxide neutral.

• Created by fixing atmospheric carbon dioxide during photosynthesis.

• Not ideal for direct energy conversion.

•Examples: straw, husks, sugar-cane, wood, etc.

Introduction: Bio-Oil

BIO-OIL INTRO | 08

• Produced from Biomass (by-products or waste).

• Dark, brown, strongly scented, liquid.

• Complex mixture of many organic components, water, etc.

• Can be single-phase or a two-phase mixture:

• Viscous, lignin-containing, phenolic oily fraction.

• Carbohydrate-rich water fraction.

• Can be used as:

• Type II fuel (17-20 MJ/kg or 60% of hydrocarbon oil).

• Flavouring & Colouring Agent (BBQ sauce & meat colouring).

• Source of chemicals or pharmaceuticals.

Bio-Oil Composition

BIO-OIL COMPOSITION | 09

• Water

• Acids

• Phenolics

• Anhydrosugars

• Carbonyls

• Furfurals

• Subject to aging at temperatures > room temperature

• Can be stabilized with methanol & ethanol

Introduction: Pyrolysis

PYROLYSIS INTRO | 10

• Definition: Thermochemical decomposition of organic matter at high temperatures in the absence of oxygen.

• Pyrolyzed biomass converts into vapours & char.

• Char (containing carbon & inorganic ash) can be separated.

• Vapours can be rapidly quenched yielding Bio-Oil & uncondensable gases.

• Gases contain light hydrocarbons.

Pyrolysis Processes & Yields

PROCESSES & YIELDS | 11

Process OperatingConditions

Bio-OilYields

CharYields

Gas Yields

Slow Pyrolysis

T ≈ 400°CTime ≈ hours <5% ~50% ~45%

IntermediatePyrolysis

T ≈ 300-600°CTime ≈ 10-30

seconds~40% ~20% ~40%

Fast Pyrolysis

T ≈ 300-600°CTime < 1 second ~75% ~15% ~10%

Choice Criteria (Scott et al, 1999)

CHOICE CRITERIA | 12

1. Simple.

2. Low Capital Investment.

3. Economical plant needs to be sited where raw materials can be easily supplied at a reasonable or no cost.

4. Should operate at the minimum possible temperature (maximizing desired product yield)

5. Bio-Oil quenching requirements are minimized using the smallest possible gas to biomass feed ratio.

6. Should be easy to scale-up.

Pyrolysis Technologies

TECHNOLOGIES | 13

Reactor Type

Simple Capital Expense

Low Temperature

Low Gas/Solid

Ratio

OperatingExpense

Easy Scale-up

BubblingFluidizedBed

Very Good

Excellent Very Good Good Very Good Excellent

CirculatingFluidizedBed

Fair Good Very Good Poor Fair Very Good

RotatingCone Fair Good Very Good Very Good Fair Poor

VortexAblative Fair Very Good Very Good Excellent Good Very Poor

VacuumProcesses Fair Excellent Excellent Excellent Poor Very Good

EntrainedFlow Excellent Excellent Very Good Very Poor Poor Excellent

Process Flowsheet: Overall

OVERALL PROCESS | 14

Process Flowsheet: Feeding

INJECTION | 15

SECTION 100

Process Flowsheet

PROCESS SHEET | 16

SECTION 200

CY = CycloneT = TankHE = Heat Exchanger

Process Flowsheet: Condensation

CONDENSATION | 17

SECTION 300

Process Flowsheet: Overall

PRINCIPLE REACTOR | 18

Pyrolysis Reactor/Furnace Overview

REACTOR OVERVIEW | 19

• Unit where the Biomass is converted to Bio-Oil Vapours,

Gases, Ash & Char via Fast Pyrolysis

• Novel Annular Reactor with Core Furnace Design

• Fluidized Bed Selected

• Based on Choice Criteria previously discussed

• New Patented Lift Tube Technology utilized for heat transfer

• Insulated Outer Shell using FiberFrax

Pyrolysis Reactor Assumptions

REACTOR ASSUMPTIONS | 20

Potential Problems & Solutions

• High Temperature – Control required (Lift Tubes Technology, Oxygen Probe

S-236)

• Risk of Explosion (Plugging) – Pressure Relief Valve & Burst Plate Required

• Monitor fluidization regime to ensure proper mixing and no hot spots.

List of Assumptions

• Dry distiller’s grain composition assumed (Jacobson, 2007)

• Heat losses of 15%

• The reaction energy of 1.058 MJ/kg (Jacobson, 2007)

• A 20L gas capacitance volume of injection

• Average Heat capacities calculated & assumed constant

• Yields assumed from literature

• The sand return energy considered immaterial

• Sand has a dpsm=169μm & ρ=2500 kg/m3

Pyrolysis Reactor/Furnace Overview

REACTOR M&E | 21

PROCESS UNIT & NAME: Principal Reactor (R-201)  

IN DIAGRAM OUT

Stream T (K)P (kPa)

Material Mass(kg/s)

Power (kW)

Tref = 25°C

*Note: The power requirements do not

correlate perfectly due to approximations of heat capacities from

literature.

Stream T (K)P (kPa)

Material Mass(kg/s)

Power (kW)

Tref = 25°C

S-115 298.72135.8

DDGN2

2.310.0087

2.240.0056

S-202 723.15109.0

Bio-OilN2

CH4CO2COH2

Char/Ash

1.162.8

0.230.190.460.050.23

739.501,333.12386.7194.27

222.46311.8782.11

S-224473.1109.0 N2 2.79 547.0

S-209873.1135.8 Sand Neglect 0

RXN 723.15 Pyrolysis 2,450.4

Total 5.1 2,999.6* Total 5.1 3,170.0*

Pyrolysis Reactor Design

REACTOR DESIGN | 22

SIDE VIEW TOP VIEW

Pyrolysis Reactor Design

REACTOR DESIGN| 23

Annual Reactor

Furnace CoreSIDE VIEW

TOP VIEW

Pyrolysis Reactor Design

REACTOR DESIGN | 24

LIFT TUBE TECHNOLOGY:

Pyrolysis Reactor Design

DESIGN DETAILS | 25

Design Details

• Reactor Operating Temperature = 450°C

• Furnace Operating Temperature = 800°C

• Reactor/Furnace Operating Pressure = Approx. 1 atm

• Wall Thickness = 0.5” (Peters, 2003)

• Material of Construction: Inconel 600

• Temperature resistance, little fouling, corrosion proof, structural

stability, high thermal conductivity

• Construction Cost Quote = ~$200,000 (Gudgeon Thermfire Inc.)

• Total Capital Investment = ~$1.2 Million

•593% of Construction Cost (includes installation, piping, labour,

instrumentation, etc.)

Pyrolysis Reactor/Furnace Control

REACTOR CONTROL | 26

Main Control:

• PI Controller Selected

• Type K Thermocouples

• Oxygen Probe (DS-300)

Minor Control:

• Omega PX-82-MV Pressure

Transducers

• Pressure Gauges

• High Temp/High Pressure

Alarms

• Fluidization Flow Control

Process Flowsheet: Overall

REGENTERATION | 27

Regeneration Reactor Overview

REGENERATION OVERVIEW | 28

•Regeneration of sand from pyrolysis reactor

•Fluidized bed

•Mixture of sand, char and ash from pyrolysis

reactor injected

•Char is burned

•Ash is entrained

•Sand is returned to pyrolysis

reactor via standpipe

Regeneration Reactor Assumptions

ASSUMPTIONS | 29

Potential Problems

• High temperature (combustion reaction) – Must control reactor temperature

and must be able to stop feeding in case of overheating

• Particle entrainment – Use baffles in reactor to block sand particles; ash

particles will still be able to escape the reactor

List of Assumptions

•Heat losses of 15% of heat of combustion

•Heat capacities used are taken at average temperatures

•Sand and ash have same heat capacity

•Injection nitrogen has negligible effect on energy balance

•Complete combustion

•Char is purely carbon

•No sand entrained

•Combustion at 400°C

Mass & Energy Balance: Regeneration Reactor

REGENERATION M&E | 30

PROCESS UNIT & NAME: Sand Regenerator (R-202) 

IN DIAGRAM OUT

Stream T (K)P

(kPa)

Material Mass(kg/s)

Power (kW)

Tref = 25°C

Stream T (K)P (kPa)

Material Mass(kg/s)

Power (kW) Tref = 25°C

S-207 673128.8

N2

CharSandAsh

0.00170.140.070.09

0.0544.1

22.0528.35

S-212 1304108.2

AirN2

CO2

Ash

0.991.22

0.5130.09

1061.791473.09516.5776.08

S-238373

108.9Air 2.6 208.07

*Note: The values are not the exact same due to assumptions in heat

capacity

S-2081034170.2

Sand 0.07 59.17

Reaction 373 2800

Total *3102.62 Total *3186.69

R-202

S-207

S-208

S-238

S-212

Regeneration Reactor Design

REGENERATION DESIGN | 31

3.5m

1.5m

Wall Thickness: 0.5”

Regeneration Reactor Design

REGENERATION DESIGN | 32

Design Details

• Reactor Operating Temperature = 1031°C

• Operating Pressure ~ 1atm

• Wall thickness = 0.5”

•Construction Material:

•Inconel 625 (high temperature)

•Maintains good properties well over 1000°C (essential)

•Construction Cost:

• $63,000

•Total Capital Investment:

• $373,590 (Includes 593% adjustment for associated costs)

Regeneration Reactor Control

REGENERATION CONTROL | 33

Main Control:

• Type K Thermocouples

appropriate for high

temperatures

•PI controller

•Eliminate offset

•Acceptable speed

Minor Control:

• Pressure transducers, gauges

• Ensure proper reactor

functionV-217

Process Flowsheet: Overall

AIR COOLER | 34

Air-Cooled H.E. Overview

AIR COOLED H.E. OVERVIEW | 35

• A series of heat exchangers are used to cool down the product gases

• The water used in the third heat exchanger (HE-303) needs to be cooled down

• Need for a suitable, environmentally friendly solution

Air Cooling

ALTERNATIVES | 36

• Chosen because of:

• Environmental impact

• Lower water consumption

• No danger of water pollution

• Lower maintenance and piping costs

• Less corrosion, fouling issues

Air Cooled H.E. Design

DESIGN CONSIDERATIONS | 37

Considerations

• Must be able to handle winter and summer conditions

• Temperature constraints

Design Assumptions

• Near constant temperature (25C)

• Average heat capacities calculated and assumed constant

• Negligible fouling on air side

Mass & Energy Balance

AC M&E | 38

PROCESS UNIT & NAME: Heat Exchanger (AC-301)  

IN DIAGRAM OUT

Stream T (K)P (kPa)

Material Mass(kg/s)

Power (kW) Tref = 25°C

Stream T (K)P (kPa)

Material Mass(kg/s)

Power (kW) Tref = 25°C

S-319 358.15218.6

H2O 13 3264 S-320 318.15204.8

H2O 13 1088

S-327 298.15 Air 144 0 S-328 313.15 Air 144 2186

Total 157 3264 Total 157 3274

Air Cooled H.E. Design Details

DESIGN DETAILS | 39

• Fin type: Integral

• Copper alloy tubing with

aluminum fins

• Dimensions:

• Triangular 2.5 in. pitch

• 4 tube rows, 2 tube passes, 3 sections, 38 tubes per row

• Total surface area required: 50,500 ft2

• Available surface area: ~66,000 ft2

• Cost: $356,080

Fins per in.: 9

Fin height: 0.5 in

Fin thickness: 0.019 in.

Air Cooled H.E. Design

DESIGN DETAILS | 40

• Air flow: Induced draft

• Better air distribution

• Fan power requirement: 6 fans with 5 kW each

Control Strategy

AIR COOLER CONTROL | 41

• Control objectives:

• Control outlet temperature of water

• Monitor process

Water in

Air

Variable speed motor

TT-2

TT-1

FT-2

Water out

SC

FT-1

FT: Flow TransmitterSC: Speed ControllerTT: Temperature Transmitter

HYSYS Simulation Check

HYSYS | 42

Bio-Oil Composition Mass FractionsGlyoxal 4.88%AcetAldehyde 2.24%H2O 32.94%CO2 0.02%CO 0.00%Methane 0.00%Hydrogen 0.00%Ethanol 15.99%FormicAcid 4.37%AceticAcid 5.72%Glycerol 9.00%Nitrogen 0.00%Acetol 7.23%Oxygen 0.00%Glucose 17.61%DDG 0.00%

Process Inherent Safety

INHERENT SAFETY | 43

• Entire plant operated essentially as an open system

• All units operate at a low pressure

• Harmful vapours combusted for energy and not

released into the environment

• At any given time, there is only a small amount of

hazardous gas since it is continuously combusted

• Natural gas utility used for start-up and heating

instead of stored propane

Process Safety Overview

LOPA | 44

Physical Protection-rupture disks-relief valves

Process Design Inherent Safety

Critical Alarms and Operator intervention-High temperature alarm-High pressure alarm

Process Economics

CAPITAL INVESTMENT | 45

Equipment Cost

Principal Reactor (R-201/FU-201) $ 1,186,000

Regeneration Reactor (R-202) $ 373,590

Storage Tanks & Hoppers (T-xxx, HO-xxx) $ 3,391,960

Heat Exchangers (HE-xxx, AC-301) $ 429,984

Pumps (P-xxx) $ 83,200

Blowers (B-xxx) $ 637,000

Cyclones (CY-xxx) $ 117,000

Total Capital Investment $ 6,218,734

Total Capital Investment

Process Economics

PROCESS ECONOMICS | 46

Expense Annual Cost

Raw Materials (DDGs, Sand) $ 26,193

Utility Costs $ 756,410

Labour/Staff Costs $ 936,000

Maintenance $ 373,124

Operating Supplies $ 55,968

Overhead $ 785,474

Insurance and Property Taxes $ 124,374

Administrative Costs $ 196,368

Research and Development $ 152,877

Distribution and Sales $ 305,754

Total Annual Operating Costs $ 3,712,546

Annual Sales Revenue* $ 5,468,750

Annual Net Income** $ 737,314

Annual Free Cash Flow $ 1,359,188

*Bio-Oil priced at $35/barrel

**After tax & depreciation

Process Economics

RETURNS & SENSITIVITY | 47

• Payback Period = 4.58 Years

• Discounted Cash Flow IRR = 21%

• Sensitive to Market Price of Bio-Oil

• Break-even at $20/barrel

• Sensitive to deals with Northern Ethanol Inc. and agricultural producers to obtain cheap or free biomass byproducts or wastes.

Conclusions & Recommendations

CONCLUSIONS | 48

• Based on this study, project appears very feasible & profitable

• Novel reactor design maximizes heat transfer efficiency

• Overall process very energy efficient

• Significant heat recovery & waste recycling

• Significant safety considerations implemented

• Recommend to WENCOR for intensification study:

• Pinch Analysis

Acknowledgements

ACKNOWLEDGEMENTS | 49

 The authors of this report wish to express their most sincere appreciation to Professor Barghi for his insight and direction in this project.  In addition, they wish to thank Prof. C. Briens, Prof. F. Berruti and Dr. L. Ferrante for their knowledge and assistance.

QUESTIONS?

Acknowledgements

ACKNOWLEDGEMENTS | 47

Process Safety Overview

HAZARD ASSESSMENT

Chemical Fire Hazard Health Hazard

Corrosive Flash Point (°C)

Auto-Ignition Temp (°C)

Prolonged Inhalation

Nitrogen No No No N/A N/A None

DDG Yes No No N/A N/A N/A

Carbon Monoxide

Yes Yes No N/A 620 Confusion, nausea, unconsciousness, death

Carbon Dioxide

No No No N/A N/A Asphyxiation, circulatory collapse

Methane Yes Yes No N/A 580 Asphyxiation, nausea, unconsciousness, muscle failure

Hydrogen Yes No No N/A 570 Explosion Risk

Bio-Oil Yes Yes Yes 50 500 Severe irritation