LIGNOCELLULOSIC ETHANOL YURIA ANAGA ALFRED LYANTO VIVIEN LEE YURIA ANAGA ALFRED LYANTO VIVIEN LEE.
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Transcript of LIGNOCELLULOSIC ETHANOL YURIA ANAGA ALFRED LYANTO VIVIEN LEE YURIA ANAGA ALFRED LYANTO VIVIEN LEE.
LIGNOCELLULOSIC ETHANOL
LIGNOCELLULOSIC ETHANOL
YURIA ANAGAALFRED LYANTO
VIVIEN LEE
YURIA ANAGAALFRED LYANTO
VIVIEN LEE
INTRODUCTIONINTRODUCTION
• Target: 77 million gallons of ethanol/year
• Switchgrass Ethanol Gasohol• Plant location: Iowa, United States
OVERVIEWOVERVIEW
• Improvements on Process – Solid storage (Silo)– Elimination of CO2 Emission– Centrifugation– Lignin Burning – CBP Scheduling– Distillation Columns– Water Recycle and Heat
Exchanger• Economic Analysis• Safety Considerations• Ethics
• Silo storage is added before grinding• To handle the hold up time between
the transport of switchgrass and the rate of switchgrass grinding
• The harvest time for switchgrass is 3 years1
1) http://www.global-greenhouse-warming.com/ethics-of-biofuel.html accesed on October 31, 2009
P-1 / GR-101Grinding
P-16 / SL-101Solids Storage
S-101
Switchgrass
IMPROVEMENTS: Solids Storage (Silo)
IMPROVEMENTS: Solids Storage (Silo)
P-5 / V-102CBP Reactor
P-8 / G-101Gas Compression
CO2 LIQUEFACTIONS-112
P-4 / V-103Pressurized Tank
liquid CO2
hydrogen gasS-106
• 98.5% of CO2 and 1.5% of H2 is produced by CBP• Compress the gas mixture to 40atm and cool it down to 12 0C to
liquefy CO2
• The pressurized tank is used to split the vapor H2 and liquid CO2 streams
• Liquid CO2 is sold to other companies e.g. for refrigerant
• The H2 stream is burnt to generate steam inside the plant2,3
• Although H2 is flammable, BUT no O2 source is available to initiate explosion
2) Smith J.M., Van Ness H.C., Abbott M.M.. Introduction in Chemical Engineering Thermodynamics 7th Ed. McGraw Hill. New York (2005)3) CRC Handbook of Chemistry and Physics (2008-2009) < http://www.hbcpnetbase.com/>
IMPROVEMENTS: Elimination of CO2 Emission
IMPROVEMENTS: Elimination of CO2 Emission
P-14 / DC-101
Centrifugation
Now
P-21 / CF-101
Centrifugation
Before
• Centritech pharmaceutical use, separate finer particle (Volume~5000L)
• Decanter continuous; higher capacity than hydrocyclone, disk-stack, basket centrifuge, and bowl centrifuge; achieve higher separation than clarifier; relatively more expensive4
4) www.lenntech.com accessed on October 31, 2009
IMPROVEMENTS: Centrifugation
IMPROVEMENTS: Centrifugation
P-14 / DC-101Centrifugation
lignin slurry
• Lignin will be burnt with 30% efficiency (ideal Carnot cycle = 51%)5 to support internal steam generation.
• 1 kg of lignin produces 1 kg of steam6:
MW 1.60=0.3kW1000
MW 1
kcal/h 1
kW 0.001162
steam kg 1
kcal 487.303935
lignin kg 1
steam kg 1
hour 1
lignin kg8457.28447 =savingsPower
1$257,940.4=0.3year 1
hours 8472
steam kg 1
$0.012
lignin kg 1
steam kg 1
hour 1
lignin kg8457.28447=savings Annual
11.27%=$2,284,925
1$257,940,4 =Cost on UtilizatiSteamon Savings Annual %
IMPROVEMENTS: Lignin Burning
IMPROVEMENTS: Lignin Burning
5) Smith. “Introduction to Chemical Engineering Thermodynamics”. McGraw-Hill.7th Edition6) Biomass program: lignin-derived co-products, U.S. Department of Energy, Energy Efficiency and Renewable Energy (2007)
P-5 / V-102CBP Reactor
• 2 staggered CBP reactors (12,000L each in batch system) are used to get a continuous process
• Seed Fermentor is used to grow the bacteria• Scheduling: one reactor reacts (36 hours
long) while another one performs: transfer out, cleaning, and transfer in IMPROVEMENTS:
CBP SchedulingIMPROVEMENTS:
CBP Scheduling
• Changing the parameters inside the distillation column to give reasonable ethanol compositions at the bottom streams
• Higher ethanol recovery increases Revenue
NewBefore
IMPROVEMENTS: Distillation Columns
IMPROVEMENTS: Distillation Columns
PRE-TREATM EN T
Liq. Waste 1
P-10 / V-105AFEX Reactor
P-12 / C-103Molecular Sieves
P-9 / C-101Preheat Distillation
P-11 / C-102Distillation
PRODUCT RECOVERY
P-7 / V-101Flash
Air
P-17 / MX-105Mixing
P-18 / HX-104Heat Exchanging
P-20 / FSP-101Flow Splitting
Liq. Waste 2
P-3 / MX-101MixingWater
P-6 / MX-103Mixing
99.8% ethanol
S-103 S-104
S-110
S-111
S-113
S-115
S-116
S-117
S-118
S-119
S-120
Recycled Water
Water Recycle• Water from the bottom
product of the distillation columns is recycled to conserve water
• Ethanol impurity from the distillation columns produces impurity to the liquid NH4OH
• The impure NH4OH is sold to cleaning company e.g. Clorox
• Water from the molecular sieve is recycled as well
Heat Exchanger• Hot liquid waste stream from flash and distillation columns
are used to preheat the raw material before AFEX reactor
IMPROVEMENTS: Water Recycle & Heat Exchanger
IMPROVEMENTS: Water Recycle & Heat Exchanger
Capacity: 77 million gallons/ yearMESP: US$ 2.01/galPayback period: 6.80 yearsNPV: US$ 76,799,000.00
Economics Analysis:MESP, Payback, NPV, & Feasibility
Economics Analysis:MESP, Payback, NPV, & Feasibility
%14.10%100*/10*837.6
/10*932.69
8
yearMJ
yearMJ
Raw Materials0.23669
Labor-De-pendent0.01760
Facility-Dependent0.60605
Laboratory QC/QA
0.00264
Consumables0.00034
Waste Treatment0.04198
Utilities0.09470
Annual Operating Cost
Economics Analysis:COST
Economics Analysis:COST
45 55 65 75 85
-$150,000,000
-$50,000,000
$50,000,000
Sensitivity Analysis: NPV vs Annual Production
Capacity
Annual Production Capacity (million gallon)
NP
V
~77
Economics Analysis:Sensitivity Analysis 1Economics Analysis:
Sensitivity Analysis 1
$0.00 $1.00 $2.00 $3.00
-$3,000,000,000
-$2,000,000,000
-$1,000,000,000
$0
$1,000,000,000
Sensitivity Analysis: NPV vs Price of Raw Mate-
rials
Switchgrass
Price of Raw Materials
NP
V
Economics Analysis:Sensitivity Analysis 2Economics Analysis:
Sensitivity Analysis 2
$1.85 $1.90 $1.95 $2.00 $2.05 $2.10 $2.15$0
$40,000,000
$80,000,000
$120,000,000
Sensitivity Analysis: NPV vs MESP
MESP (per gal)
NP
V
NPV= 0, when MESP~ $1.79
Economics Analysis:Sensitivity Analysis 3Economics Analysis:
Sensitivity Analysis 3
• Basic Safety Training for all employees and specific training for corresponding operators
• Regular Maintenance for all unit operations
• Install Basic Safety Equipment e.g. safety shower
• Ground all the equipment to avoid statics• Install flare-stack in the middle of the
plant to vacuum all the pipe residues and burn it
Safety Considerations:Overall
Safety Considerations:Overall
P-1 / GR-101
Grinding
• Safety Considerations:– Fire explosion due to the dust
from switchgrass– Ignition source: static and
overheat of the agitator• Preventions:
– Install baghouse filtrations– Spray small amount of water
(reduce the floating dust)– Install exhaust ventilation
Safety Considerations:Grinder
Safety Considerations:Grinder
P-10 / V-105
AFEX Reactor
7) Lecture slides
Safety Considerations:AFEX Reactor
Safety Considerations:AFEX Reactor
• Safety Considerations:– High pressure (21 atm), high
temperature (900 C)– Ammonia corrosive, ammonia slip-
toxic, and cause explosion in the presence of air
• Preventions:– Install controllers to monitor the
ammonia, pressure, and temperature– Select proper material for AFEX, that
can withstand 2440 F and 23.1 atm6
– Install exhaust ventilation– Highly closed system
Material (alloys)
Strength (MPa) Cost
(USD/lb.)Criteria FulfilledYield Tensi
leSS 316/317 515 205 3.50 1, 2, 3, 4
SS 304 515 205 3.15 1, 2, 3, 4Inconel 600 675’ 310 9.43 1, 2, 3, 4Monel 400 482 193 8.39 1, 2, 3Nickel 200 496 172 15.00 1, 2, 3Hastelloy N 755 385 40.00 1, 2, 3, 4
‘ at -200-300oC, others are at room T, atmospheric P
Considerations:1. Compatible with ammonia and ammonium hydroxide2. Chromium Oxide Layer (to prevent corrosion)3. Stand mild scratching from 2 mm switchgrass4. High strength to overcome very high pressure P= 65 atm, T= 90oC
Safety Considerations:AFEX Reactor’s Material
Safety Considerations:AFEX Reactor’s Material
Thermal Expansion and Strength Data: SS304Thermal Expansion and Strength Data: SS304
8. Rempe, J.L. et al. High Temperature Thermal and Structural Material Properties for Metals used in LWR Vessels. ICAPP 2008
Safety Considerations:AFEX Reactor’s Material
Safety Considerations:AFEX Reactor’s Material
P-5 / V-102
CBP
• Safety Considerations:– High temperature (650 C)– Flammable liquids and vapor inside
CBP e.g. ethanol, acetic acid, lactic acid, H2
– Highly corrosive to metal (NaCl from the nutrient)
• Preventions:– Install controllers to monitor the
temperature and pressure– Select proper material for CBP, that
can withstand the corrosives, 1990 F, and 1.1 atm5
– Highly closed system Safety Considerations:CBP Reactor
Safety Considerations:CBP Reactor
Material (alloys)
Strength (MPa) Cost
(USD/lb.)Criteria FulfilledYield Tensil
eSS 316/317 515 205 3.50 1, 2, 4, 5
SS 304 515 205 3.15 2, 4, 5
Inconel 600 675* 310 9.43 1, 2, 3, 4, 5
Monel 400 482 193 8.39 1, 2, 3, 4Nickel 200 496 172 15.00 1, 2, 3, 4Hastelloy N 755 385 40.00 1, 2, 3, 4, 5
Considerations:1. Compatible with Acetic acid2. Compatible with Lactic acid3. Compatible with NaCl (nutrients)4. Compatible with ethanol 5. High strength to overcome T= 65oC, P= 1 atm
* at -200-300oC, others are at room T, atmospheric P
9The mean linear thermal expansivity is found to be 11.4 × 10−6 K−1
9. http://www.sciencedirect.com accessed on November 4, 2009
Safety Considerations:CBP Reactor’s MaterialSafety Considerations:CBP Reactor’s Material
• Problems:– Competition with food production– Wildlife habitat
• Alternative Solutions:– Rotational farming with crops– Donating part of the company’s profit for research
in agricultural area and wildlife conservation– Switchgrass is a native plantation in Iowa habitat
for wildlife– Volunteering in wildlife conservation
organization
Ethics:Land Competition
Ethics:Land Competition
• Problems:– Air pollution due to CO2 emission
• Alternative Solutions:– 115% CO2 emission saving (comparing with 40%
only for corn ethanol)10
– Selling some CO2 emitted in liquid form
– The CO2 will be consumed by the switchgrass– Building the plant in a location that is far from
residential area– Ethanol fuel is a cleaner fuel, based on grams of C
per MJ energy generated11
10http://climateethics.org/?p=18 accessed on October 31, 200911CRC Handbook 89th Edition. 2008-2009 Accessed on 31st October 2009.
Ethics:Air Pollution
Ethics:Air Pollution
This process design is practicable because:• The NPV is positive• The payback time is 6.80 years• The energy consumed is 10.14% of the energy
produced• The production process is safe• Alternative solutions can be used to minimize
ethical problems
ConclusionConclusion
ReferencesReferences
• MSDS References1. Jtbaker, MSDS – Lactic Acid. 19th May 20082. Airgas,MSDS – CO2.11th April 2005
3. Air Product, MSDS – Hydrogen. June 19944. ATCC, MSDS – T. Saccharolyticum. February 20025. Megazyme, MSDS – C. Thermocellum. 1st September 20096. Becton, Dickinson and Company, MSDS – Nutrients. 30th June 20037. Temple-Inland, MSDS – Hemicellulose. January 20098. ScienceLab.com, MSDS – Cellulose. 6th November 2008
9. Weyerhaeuser. MSDS – Lignin. 15th October 2009. 10. Praxair Technology Inc.. MSDS – Ammonia Anhydrous. (2006)
11. ScienceLab.com, Inc.. MSDS – Ammonium hydroxide. 6th November 2008. 12. Fisher Scientific. MSDS –Ethanol. 27th July 1999. 13. ScienceLab.com, Inc.. MSDS – Acetic Acid. 10th September 2005.
• Material References1. www.azon.com accessed on October 31, 20092. www.quantumalloys.com accessed on October 31, 20093. http://www.aircraftmaterialsuk.com/data/electronic/al200.html accessed on October 31, 20094. www.haynesintl.com accessed on October 31, 20095. www.metalprices.com accessed on October 31, 2009
THANK YOUTHANK YOU
QUESTIONS?QUESTIONS?
• Precaution:– Corrosive– Eyes, skin, and respiratory tract burns– Ammonia slip toxic gas formation e.g. NOx
– Forms explosive mixture with air• Prevention:
– Gas mask for operators– Ammonia concentration sensor– Keep sources of direct heat and ignition source– Install exhaust ventilations
• Accidental Release Solution:– Fire explosion: waterspray, CO2, fog, or dry chemical– Ammonia leak: evacuate all workers, shut down the plant, clean
up the gas leakage
Safety: Primary Chemicals Ammonia AFEX reactor,
Condenser
Safety: Primary Chemicals Ammonia AFEX reactor,
Condenser
For storage (in cylinders):Temperature < 520 CCylinders should be equipped with pressure relief device
• Precaution:– Dust generation fire explosion– Irritation of the respiratory system
• Prevention:– Dust mask for operators– Baghouse filtrations– Keep sources of direct heat and
ignition source– Install exhaust ventilations/fume
hood• Accidental Release Solution:
– Small fire: use dry powder– Big fire: use waterspray, fog, or
foamSafety: Primary Chemicals SwitchgrassSilo storage,
Grinder
Safety: Primary Chemicals SwitchgrassSilo storage,
Grinder
• Precaution:– Flammable liquid and vapor– Respiratory tract irritation, central nervous system
depression, moderate skin and eyes irritation– Vapors may form an explosive mixture with air
• Prevention:– Use explosion-proof ventilation equipment– Eyewash facility and a safety shower– Use general or local exhaust ventilation
• Accidental Release Solution:– Spills/ leaks: absorb spill with inert material, then place in
a suitable container– Small fires: use dry chemical, carbon dioxide, water spray
or alcohol-resistant foam– Large fires: use water spray, fog, or alcohol-resistant foam
Safety: Primary Chemicals Ethanol CBP, all separation
unit ops
Safety: Primary Chemicals Ethanol CBP, all separation
unit ops
• Precaution:– Causes damage to lungs, cardiovascular system, central
nervous system, skin and eyes irritation, and respiratory tract– Contact with rapidly expanding gas, liquid, or solid can cause
frostbite• Prevention:
– CO2 concentration controller
– Wear a full face shield (working with cryogenic liquid)– Use process enclosures or local exhaust ventilation– Avoid dispersal of spilled material and runoff and contact with
soil, waterways, drains, and sewers– Use only with adequate ventilation– Prevent entrapment of liquid in closed systems or piping
without pressure relief devices MATERIAL!• Accidental Release Solution:
– Spills/ leaks: Shut off gas supply if this can be done safely– Isolate area until gas has dispersed
Safety: Primary Chemicals Carbon dioxide CBP, compressor, and condenser
Safety: Primary Chemicals Carbon dioxide CBP, compressor, and condenser
• Precaution:– Corrosive and flammable– Causes burns to any area of contact (harmful if swallowed
or inhaled)• Prevention:
– Vent hood– Isolate hazard area– Use industrial or local exhaust (to prevent
dispersion)ventilation– Isolate from any source of heat or ignition– Prepare a full-face piece positive-pressure, air-supplied
respirator (for emergency)• Accidental Release Solution:
– Spills/ leaks: ventilate area of leak or spill, collect liquid in an appropriate container or absorb with an inert material, and place in a chemical waste container
– Use CO2 or water spray to extinguish the fire
Safety: Primary Chemicals Acetic and Lactic acid CBP, centrifuge, flash
Safety: Primary Chemicals Acetic and Lactic acid CBP, centrifuge, flash
• Precaution:– Flammable (explosive hazard when concentrations exceed
4%)– High concentrations that will cause suffocation/ asphyxiant
• Prevention:– Eliminate any possible sources of ignition, and provide
maximum explosion-proof ventilation– Provide natural or explosion-proof ventilation adequate to
ensure hydrogen does not reach its lower explosive limit of 4%
– Prepare air supplied respirators• Accidental Release Solution:
– Spills/ leaks: ventilate area of leak or spill, collect liquid in an appropriate container or absorb with an inert material, and place in a chemical waste container
– Use CO2, water spray, dry chemical, or fog to extinguish the fire
– Evacuate all personnel from danger area– Stop flow or gas if without risk while continuing cooling
water spray
Safety: Primary Chemicals Hydrogen gas CBP, compressor, and
condenser
Safety: Primary Chemicals Hydrogen gas CBP, compressor, and
condenser
Safety: Primary Chemicals Bacteria CBP
Safety: Primary Chemicals Bacteria CBP
• Precaution:– Eyes and skin irritant, long term exposure to dusts can
cause respiratory irritation and coughing, an allergic reaction is possible with asthmatics
• Prevention:• Respirator for solid and liquid particulates, including dusts
and mists• Accidental Release Solution:
– Spills/ leaks: contain the spill and decontaminate using suitable disinfectants such as chlorine bleach or 70% ethanol
– Before disposing cultures and exposed materials, autoclave at 121oC for 20 minutes
– Use water or foam to extinguish the fire
Safety: Primary Chemicals Nutrients CBP
Safety: Primary Chemicals Nutrients CBP
• Precaution:• Irritating to eyes, respiratory system, and skin
• Prevention:• Keep container tightly closed• Do not breathe dust
• Accidental Release Solution:– Spills/ leaks: use cleansing agent (water)