Cassava bioethanol production Cassava bioethanol bioethanol

Cassava bioethanol
bioethanol production
production
Cassava
by
Dr. Kuakoon Piyachomkwan
Cassava and Starch Technology Research Unit (CSTRU)
National Center for Genetic Engineering and Biotechnology (BIOTEC)
National Science and Technology Development Agency (NSTDA)
South - South Technology Transfer: Ethanol Production from
Cassava
Siam City Hotel, Bangkok
22-24 June 2011
World Ethanol Production
by continent in %
South America
N&C America
35.1%
45.9%
Asia
Europe
Africa
10.5%
7.6%
0.9%
Total production 77,000 mln litres (2008)
World Ethanol Consumption
Potable 11.5%
Industrial 8.8%
(7,375 mln litres)
(5,643 mln litres)
Fuel 79.6%
(51,044 mln litres)
Total 64,126 million litres (2007)
Fuel Ethanol Market
Thailand EU
China India 0.5%
4%
2.9% 0.6%
Others
1.6%
Canada
1.4%
Brazil
38%
USA
51%
63,421 million litres (2008)
World Ethanol Production by Feedstock
Synthetic
Sugar crops
55%
6%
Grains
37%
Others
2%
H12O
O + Yeast
CC66H
12 66+ Yeast
Glucose
Glucose
100grams
grams
100
2CO2 ++
2CO
2
Carbondioxide
dioxide
Carbon
48.89grams
grams
48.89
2C2H
H OH
2C
2 55OH
Ethanol
Ethanol
51.11grams
grams
51.11
The Gay-Lussac equation for ethanol production
from glucose by fermentation
Feedstock for ethanol production
Sugar crops
Cellulose
Sugar cane
Rice straws
Molasses
Bagasse
Sugar beets
Corn cops
Sawdust
Starch crops
Corn Cassava
Rice Wheat Potato
Sugar crops
Starch crops
Cellulose
Liquefaction
Pretreatment
Juice Extraction
Saccharification
Enzyme Hydrolysis
Diluted Molasses
Sugar syrup
Fermentation
Distillation & Dehydration
Anhydrous ethanol
Ethanol yields from various feed stocks
To produce 100 litres of ethanol* it takes:
4,000 l
of cheese whey
1,400 kg
of sweet sorghum
1,270 kg
of sugar cane
1,250 kg
of Jerusalem artichoke
1,030 kg
of sugar beet
850 kg
of potatoes
545 kg
of cassava
385 kg
of wood
360 kg
of molasses
368 kg
of maize (wet milling)
258 kg
of maize (dry milling)
260 kg
of wheat
230 kg
of millet
225 kg
of paddy rice
*) average values actual yields may vary depending on
Industrial production of ethanol
Brazil
USA
Europe
Russia
- Sugarcane
- Cereal grains (mostly corn)
- Cereal grains, beets
- Cereal grains, beets
Cassava: The winner
The Key of Success
-All year round planting-
The Key of Success
“Growth tolerance to poor
environmental condition ”
The Key of Success
“All year round planting/harvesting”
The Key of Success
“High root productivity”
Thai average = 20-25 T/ha
World = 11-12 T/ha
Reported ~ 90 T/ha
The Key of Success
“Continuous development of high
yield-improved varieties”
Cassava Varieties
Rayong5
Rayong90
KU50
Huaybong 60
The Key of Success
“Less input in planting
and harvesting”
The Key of Success
“High-quantity/quality
carbohydrate source”
The Key of Success
Well developed technology
for raw material preparation
Simple conversion to dried chips for
effective storage and transportation
Dried Chips
1.
3.
2.
4.
Chemical composition of cassava chips and corn grain
Composition
Moisture (% wet basis)
Starch (% dry basis)
Protein (% dry basis)
Fat (% dry basis)
Ash (% dry basis)
Crude fiber (% dry basis)
*Source: Watson, 1984
Content
Corn grain* Cassava chips
7-23
10-14
64-78
75 – 85
8-14
1.5 – 3
3.1-5.7
0.2
1.1-3.9
2–4
1.8-3.5
3–4
Raw materials
Raw materials
Steeping with water
Grinding
Grinding
Liquefaction
Protein
Starch Separation
/ Fiber
Saccharification
Starch hydrolysis
(Liquefaction and Saccharification)
Fermentation
DDGS
Fermentation
Ethanol
Yeast
Ethanol
(a)
368 kg of corn /100 liters of ethanol
(b)
258 kg of corn /100 liters of ethanol
Ethanol production from corn by (a) Wet milling and (b) Dry grinding process
Raw material preparation
in ethanol production process
Air bag filter
Hopper
1st milling
Metal and stone detector
2nd Milling
Bucket elevator
Sifter
Chip grinding and
slurry preparation
Mixing tank
To Liquefaction
Root Hopper
Root Peeler
Root Chopper
Root Washer
Root Rasper
st
1 fine extractor
(vertical type)
2nd coarse
extractor
2nd fine extractor
(vertical type)
1st coarse extractor
(Horizontal type)
Starch
milk tank
Screener
3th coarse
extractor
De-sand
cyclone
M
M
Agitator
tank
Starch slurry (without fiber) prepared from fresh root
Separator
Hydrocyclone
To liquefaction section
Concentrate Starch
milk tank
The Key of Success
Improved technology
for ethanol production
6 kg
Root
Chopping
Drying
2.5 kg
Chips
Grinding
Slurry & Cooking
Liquefaction
Saccharification
55OC
Fermentation
30OC
Distillation
Conventional process of
ethanol production from cassava
Dehydration
1L
105OC
99.5%Ethanol
Cooking
Liquefaction
Ethanol
Fermentation Saccharification
Cassava Chips
α-amylase
glucoamylase
yeast
Milling
Distillation
&Dehydration
Cooking & Liquefaction
Saccharification
Fermentation
A pilot plant of ethanol production
located at The Thai Liquor Distillery Org, Chachengsao province
Raw material preparation
Cooking
Process of ethanol production from cassava chips
located at The Thai Liquor Distillery Org, Chachengsao province
Saccharification and Fermentation
Distillation and Dehydration
Process of ethanol production from cassava chips
located at The Thai Liquor Distillery Org, Chachengsao province
20
18
15
16
ethanol
14
10
12
pH
10
5
TSS
8
glucose
0
6
0
20
40
เวลา (ชั่ ว(hr)
โมง)
Time
60
O
active cell
20
25
20
7
22
Active Cellx10 (cells/ml)
30
24
25
Total Soluble Solid ( Brix)
6.0
5.8
5.6
5.4
5.2
5.0
4.8
4.6
4.4
4.2
4.0
3.8
3.6
3.4
3.2
3.0
glucose and ethanol (%w/v)
pH
- Conventional process -
15
10
5
0
80
glucose
ethanol
TSS
pH
Active cell
Ethanol production from cassava chips by conventional process (CF)
Conditions: Ground cassava chips (25% DS); Liquefaction by 0.1% α-amylase at 95°C, 2 hrs; Saccharification
by 0.1% glucoamylase at 55°C, 15 hrs; Fermentation by yeast, Saccharomyces cerevisiae SC90, at 32 °C )
Cassava
Cassava
Rough Grinding
Rough Grinding
Sand Separation
Sand Separation
Liquefaction
(100 oc)
24-36
Hours
Liquefaction
Saccharification
Fermentation
Distillation
(a)
(100 oc)
72
Hours
o
(60 c)
(30 oc)
36-72
Hours
Simultaneous
Saccharification & (30 oc)
Fermentation, SSF
Distillation
(b)
Ethanol Production Process from cassava by (a) Normal Process
and (b) Simultaneous Sacharification and Fermentation (SSF)
Simultaneous Saccharification and Fermentation, SSF
Cassava Chips
α-amylase
glucoamylase
yeast
Milling
Cooking & Liquefaction
SSF
Distillation
&Dehydration
25
40
35
glu-cf
30
active cell-ssf
7
active cell x10 (cells/ml)
ethanol and glucose (% w/v)
20
25
15
active cell-cf
eth-cf
20
10
15
eth -ssf
10
5
5
glu-ssf
0
0
0
20
40
tim e (hrs.)
Ethanol production from cassava chips by
conventional (CF) and SSF process
60
80
glu -C F
glu -S S F
eth-C F
eth-S S F
act-cell-C F
act-cell-S S F
Conditions: Ground cassava chips (25% DS); Liquefaction by 0.1% α-amylase at 95°C, 2 hrs; Saccharification
by 0.1% glucoamylase at 55°C, 15 hrs; Fermentation by yeast, Saccharomyces cerevisiae SC90, at 32 °C.
For SSF process, glucoamylase was added with yeast.
Production of ethanol from cassava chips
by CF and SSF process
Parameter
Process
CF
SSF
Ethanol concentration (%w/v)
10.01+ 0.40
10.05+0.13
Yield (g ethanol / g cassava chip)
0.400+ 0.010
0.402+ 0.013
Yield (g ethanol / g starch)
0.504+ 0.08
0.503+ 0.010
89
89
% Fermentation Efficiency
Simultaneous Saccharification and Fermentation, SSF
Cassava Chip
- Moisture 15 %
- Starch content 65% (wet basis)
362.17 T/D
85.00% TS
Milling
1,248.50 T/D
Water
Mixing
1,794.43 T/D
17.16% TS
Steam
Liquefaction
120 T/D
1,914.43 T/D
16.08% TS
SSF
Fermentation
CO2
114.98 T/D
1,799.45 T/D
7.42%(w/w) Alcohol
Spent wash recycle
177.53 T/D
6.23 T/D
0.50 T/D
Thick Slop
1,496.84 T/D
6.5% TS
Distillation
124.58 T/D
95% Alcohol
Spent wash recycle
Fusel oil
Molecular Sieve
Dehydration
Fuel Ethanol
118.35 T/D or
150,000 L/D
Mass Balance of Ethanol Production
from Cassava Chip by SSF process
T/D = Ton/Day, TS = Total Solid ,L/D =Liter/day
Fermentation efficiency 90%, Distillation efficiency 98.5%
Simultaneous Liquefaction, Saccharification
Cassava Chips
and Fermentation, SLSF
“Raw-starch
digesting enzyme”
yeast
Milling
Distillation
&Dehydration
SINGLE STEP
&
UNCOOKED
process
SLSF
Cooking
Liquefaction /Saccharification
+
Fermentation
Ethanol
Cereal starches
Corn
Rice
(55%hydrolysis)
Wheat
(65%hydrolysis)
(40%hydrolysis)
Root & tuber
starches
Cassava
(50%hydrolysis)
Potato
(20%hydrolysis)
SEMs of various starches treated with
granular starch hydrolyzing enzymes (GSHE)
Corn
Cassava
6 - hr
incubation
12 - hr
incubation
24 - hr
incubation
48 - hr
incubation
SEMs of corn and cassava starches treated with granular
starch hydrolyzing enzymes (GSHE)
(
Ethanol concentration (%w/w)
)
12
0.125
10
0.125 Pretreat
8
0.25
6
0.25 Pretreat
4
0.50
2
0.50 Pretreat
0
0
10
20
30
40
50
60
70
80
Fermentation time (hr)
Ethanol concentration produced from cassava chips (25%DS) with and without
alkali pretreatment by granular starch hydrolyzing enzymes (0.125-0.5% by wt)
in SLSF process
5.8
11
5.4
5.2
5.0
pH
4.8
4.6
4.4
4.2
4.0
3.8
3.6
3.4
Glucose and ethanol content (%w/v)
5.6
TSS
22
Ethanol
10
8
4
7
6
3
TS
5
4
2
pH
3
2
1
3.0
0
1
0
10
20
30
40
50
60
70
18
16
14
12
10
8
6
4
2
Glucose
0
20
5
9
3.2
24
6
Total solid, TS (%w/w)
12
Total soluble solid, TSS (OBrix)
6.0
0
80
Time (h)
Ethanol production from cassava chips by SLSF process
Conditions: Ground cassava chips (25% DS); Liquefaction and Saccharification by 0.25% granular starch
hydrolyzing enzymes and Fermentation by yeast, Saccharomyces cerevisiae, at 32 °C
Conventional process
Today’s process
1. Cassava chips
1. Cassava chips
Future process
1. Cassava chips
2. Milling / Cooking
2. Milling / Cooking
3. Liquefaction
3. Liquefaction
(100oC, 2 hr)
4. Saccharification
(60oC, 15-24 hr)
5. Fermentation
(100oC, 2 hr)
4. Simultaneous
Saccharification and
Fermentation (SSF)
(30oC, 36-48 hr)
(30oC, 36-48 hr)
6. Filtration& Distillation
2.Milling / Uncooked
3. Simultaneous
Liquefaction
Saccharification and
Fermentation
(30oC, 36-48 hr)
4. Filtration & Distillation
5. Filtration& Distillation
Ethanol
Ethanol
Ethanol
The Key of Success
Various forms of cassava can be used
The Key of Success
≈ 4 million tons/year
(12% moisture content)
≈25 million tons/year
(65-70% moisture content)
Roots
Water
Chips
≈ 2-3 million tons/year
(12% moisture content)
Pulp
Starch
≈ 3 million tons/year
(70% moisture content)
Composition of cassava feedstock
Composition
(% dry basis)
Roots
Chips
Starch
Fiber content
1.5-6.0
2-5
nil
Protein
1.5-6.0
2.0-2.5
0-0.3
Ash
1.5-6.0
2.0-3.5
0.1-0.5
Starch content
70-85
Starch content
(wet basis)
(%MC)
25-30
60-75
85-90
(65)
(10)
(12)
70-85
97-100
Starch slurry (with fiber) prepared from fresh root
PROBLEM: At high total solid content
Roots
Viscosity
Flowability
Processing effectiveness
Chips
Starch
Ethanol production from cassava fresh roots
Ground fresh roots (≈35-40% DS)
Total solid adjustment (≈20% DS) by water addition
(feedstock to water ratios ≈ 1:0.5 to 1:1)
Liquefaction
Saccharification and Fermentation
Fermented mash with
8% (w/w) or 10% (v/v) ethanol
VHG (very high gravity) technology in fuel alcohol production
To increase the alcohol concentration to
18% (v/v) or 14.6% (w/w)
Increase total solid/starch content
(or increase the feedstock to water ratio)
VHG (very high gravity) technology in fuel alcohol production
1.
Increased plant capacity
2.
Increased plant efficiency - reduction in labor costs
3.
reduction in energy costs - less heating/cooling of mash, less
water to process in the still, optimum ethanol for efficient
distillation, lower solids in the still
4.
reduction in inputs - decreased water usage
Cassava and Starch Technology Research Unit
VHG technology development for cassava roots
Mash viscosity reduction
Ethanol production from cassava fresh roots
Ground fresh roots (≈35% DS)
(feedstock to water ratios ≈ 1 : 0.1)
Mash viscosity reduction
Liquefaction
Saccharification and Fermentation
Fermented mash with
16-18% (v/v) ethanol
SSF process
VHG - SSF process
20
Ethanol concentration (%v/v)
18
16
14
12
10
8
6
4
2
0
0
10
20
30
40
50
60
70
80
Fermentation time (hr)
Ethanol concentration during fermentation of cassava fresh roots
by SSF and VHG-SSF process
Raw material: moisture content = 65%, starch and sugar contents = 85 and 6.25% dry basis, respectively
Condition: SSF: 20% dry solid, VHG-SSF: 35% dry solid
Sun
Drying
Water
59 Tons
Cassava Chip
(moisture content = 14%)
41 Tons
Fresh Root
(moisture content = 60-70%)
100 Tons
VHG Technology
Milling
Process water saving Development
Process water
99 Tons
Mixing
(total solid = 25%)
140 Tons
Ethanol Fermentation
Energy Saving
18.5%
Energy Consumption
(MJ/L ethanol)
12
10
Dehydration
8
Distillation
6
4
Fermentation
2
Root Preparation
&Liquefaction
0
SSF process
VHG/SSF
process
Estimated reduction on energy consumption of ethanol production
by VHG-SSF process
Water
H2O
H2O
Less by using
H2roots
O
fresh
Energy
Energy
Energy
Energy
Less by
using
fresh roots
Less by using
SLSF process
Energy
Energy
Less by using
VHG process
THANK YOU FOR YOUR ATTENTION
http://www.cassava.org/
aapkrs@ku.ac.th