Calculating Yield of Ethanol from Sucrose and its Process Intermediate Products
This Article explained about calculation of ethanol yield from various feed stocks (Intermediate products) in sugar manufacturing process like sugarcane juice, secondary juice, syrup, A-molasses, B- heavy molasses and final molasses .. etc.
Calculating theoretical yield of ethanol from sucrose
The chemical equation from sucrose to ethanol can be written as ( Stoichiometric Equation )
C12 H22O11 + H2O C6 H12 O6 + C6 H12 O6
4 C2H5 OH + 4 CO2
Sucrose Glucose + Fructose
Ethanol (Ethyl Alcohol)
Molecular weight of sucrose – 342.30 gm/mol or kg/kmol
Molecular weight Glucose/Fractrose – 180.16 gm/mol or kg/kmol
Ethyl Alcohol Molecular weight – 46.07 gm/mol or kg/kmol
Molecular weight of carbon dioxide – 44.01 gm/mol or kg/kmol
Molar mass balance (kmol x kg/kmol)
1 x 342.30 4 x 46.07 + 4 x 44.01
Mass balance percentage of the above equation
100% of Sucrose 53.84% ethanol + 51.43 % carbon dioxide
The density of anhydrous ethanol (100%) is 0.78934 Kg/L at 20°C
So Theoretical ethanol production from sucrose (100 kg) = 53.84 / 0.78934 = 68.2 Liters
Calculating theoretical yield of ethanol from glucose/Fructose (Reducing Sugars)
The chemical equation from reducing sugars to ethanol can be written as ( Stoichiometric Equation )
C6 H12 O6 2 C2H5 OH + 2 CO2
Glucose/Fructose Ethanol (Ethyl Alcohol)
Molecular weight Glucose/Fractrose – 180.16 gm/mol or kg/kmol
Ethyl Alcohol Molecular weight – 46.07 gm/mol or kg/kmol
Molecular weight of carbon dioxide – 44.01 gm/mol or kg/kmol
Molar mass balance (kmol x kg/kmol)
1 x 180.16 2 x 46.07 + 2 x 44.01
Mass balance percentage of the above equation
100% of Glucose 51.14% ethanol + 48.86 % carbon dioxide
The density of anhydrous ethanol (100%) is 0.78934 Kg/L at 20°C
So Theoretical ethanol production from sucrose (100 kg) =51.14 / 0.78934 = 65 Liters
Fermentation Efficiency:
Fermentation is bio chemical process in which organic compounds converted in to simple organic compound by enzymes which is secreted by micro-organism.
The ratio between Practical yield to Theoretical yield
Theoretical Yield = (Molasses consumed x Fermentable sugar % * 650) / 100
Hence One ton Fermentable sugar will give 650 Liters of Absolute alcohol.
Practical Yield = (Total wash production x Alcohol percentage in wash) / 100
Fermentation Efficiency
Distillation efficiency :
The distillation efficiency is the ratio of the mass of ethanol in the final product to the mass of ethanol in the feed (wash) to the distillery.
Distillation Efficiency is the ration of Actual Alcohol production to Alcohol in wash distilled
Actual Alcohol Production
Hence 175 proof is equal to 100 percentage alcohol (Absolute Alcohol)
Alcohol in Wash Distilled )
Distillation Efficiency
Overall Efficiency
Fermentation efficiency *
Various feed stocks in sugar process for ethanol production
The yields of ethanol from various feed-stocks available in a cane sugar process
Primary Juice / Mixed juice / Secondary juice
Clarified juice/ Concentrated clear juice (Syrup)
B Heavy Molasses / Final Molasses
Ethanol production from sugarcane juice (Mixed juice / Clarified Juice/ Secondary juice )
Taken one example:
S.NO | Particulars | UOM | Mixed Juice | Remarks |
1 | Brix of the Material | oC | 14.5 | 13 to 16 |
2 | Purity of the material | % | 81 | 78 to 84 |
3 | Reducing Sugars (RS) | % | 0.6 | 0.5 to 0.7 |
4 | Un Fermentable Sugars (UFS) | % | 0.1 | 0.1 to 0.2 |
5 | Fermentation Efficiency (FE) | % | 90 | 88 to 91 |
6 | Distillation Efficiency (DF) | % | 98.5 | 98 to 99% |
7 | Sucrose % (Pol) | % | 11.745 | (Brix) x (Purity ) / 100 |
8 | Total Reducing sugars (TRS) | % | 12.345 | Sucrose % + Reducing Sugars% |
9 | Fermentable sugars (FS ) | % | 12.245 | TRS – UFS |
10 | Yield of Ethanol | Ltrs/MT | 71 | FS x 0.65 x FE x DF x 10) |
Ethanol production from sugarcane molasses (B Heavy and Final Molasses)
Taken one example for B-Heavy molasses
S.NO | Particulars | UOM | B – Heavy Molasses | Remarks |
1 | Brix of the Material | oC | 83 | 78 to 85 |
2 | Purity of the material | % | 49 | 45 to 55 |
3 | Reducing Sugars percent (RS) | % | 12 | 10 to 14% |
4 | Un Fermentable Sugars (UFS) | % | 1.2 | 1 to 1.5% |
5 | Fermentation Efficiency (FE) | % | 90 | 88 to 91 |
6 | Distillation Efficiency (DF) | % | 98.5 | 98 to 99% |
7 | Sucrose % (Pol) | % | 40.67 | (Brix) x (Purity ) / 100 |
8 | Total Reducing Sugars (TRS) | % | 52.67 | Sucrose % + Reducing Sugars% |
9 | Fermentable Sugars (FS ) | % | 51.47 | TRS – UFS |
10 | Yield of Ethanol | Ltrs/MT | 297 | FS x 0.65 x FE x DF x 10) |
Name of Feed Stock | Purity | Brix% | Pol% (sucrose) | Reducing sugars % by weight | Unfermentable sugars by Weight | Approx.Sp. Gravity |
Primary juice | 80 to 86 | 16 to 22 | 12 to 18 | 0.5 to 0.8 | 0.2 to 0.5 | 1.071 |
Secondary juice | 78 to 86 | 10 to 14 | 7 to 12 | 0.2 to 0.5 | 0.2 to 0.4 | 1.043 |
Mixed juice | 78 to 86 | 12 to 15 | 9 to 13 | 0.4 to 0.8 | 0.2 to 0.4 | 1.056 |
Clarified juice | 78 to 86 | 12 to 15 | 9 to 13 | 0.4 to 0.8 | 0.2 to 0.4 | 1.061 |
B Heavy Molasses | 48 to 55 | 78 to 84 | 36 to 47 | 10 to 14 | 1 to 1.5 | 1.4 |
Final Molasses | 28 to 34 | 88 to 92 | 25 to 32 | 12 to 18 | 1.2 to 2 | 1.4 |
Online Calculator for Yield of Ethanol
Advantages while using Clear juice as a feed stock of Ethanol production:
1. Clean substrate as compared to molasses therefore juice fermentation gets good fermentation rate & efficiency.
2. Biochemical Oxygen Demand (BOD) & Chemical Oxygen Demand (COD) of the effluent will be much less as compared to molasses; therefore effluent treatment cost is very less.
3. Quality of the alcohol from clear juice is better than the alcohol drawn from molasses.
4. Cane does not have high content of dissolved solids and therefore there is no scaling and blocking in distillation column as it forms with the use of molasses.
5. Fermentation time less than the fermentation time taken by the molasses.
6. Colour of the effluent is less compared to spent wash from molasses based alcohol production.
Some Disadvantages while using Juice as a feed stock of production of Alcohol :
1 . The cane juice cannot be stored in bulk for any considerable length of time as it is highly contaminated with bacteria & yeast starts to ferment spontaneously very rapid.
2. This means the distillery unit must be located in close proximity to the cane mill
3. Cane juice normally becomes quickly infected with bacteria and yeast in the crushing process. So Mixed juice not preferable to directly take fermentation. It is better to go first effect or second effect juice
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35 thoughts on “Ethanol production from various feed-stocks in sugar process | Yield of Ethanol”
Amresh
(September 1, 2018 - 5:37 pm)100% of Sucrose = 53.84% ethanol + 51.43 % carbon dioxide
How possible elaborate please.
siva alluri
(September 2, 2018 - 3:26 pm)According to Stoichiometric Equation
C12 H22O11 + H2O = 4 C2H5 OH + 4 CO2
1 x 342.30 = 4 x 46.07 + 4 x 44.01
Now consider sucrose 1 gm then
1 = (4 x 46.07/ 342.30 ) + ( 4 x 44.01 / 342.30) = 0.5383 + 0.5143
BHARATKUMAR MAGDUM
(September 24, 2018 - 5:02 pm)Good calculation Madam, But ethanol production from B heavy ,& final molasses is approximately equal (20 lit difference) so what is the profit from B heavy molasses
Thank you for your valuable calculation
siva alluri
(September 24, 2018 - 5:52 pm)For BH and final molasses yield approximately differ 50 to 60 Lt./MT
mahbub rahman
(December 23, 2018 - 6:34 pm)good article <3
siva alluri
(December 26, 2018 - 4:28 pm)Thank you Mr.mahbub rahman
Rajani Hazarika
(December 27, 2018 - 3:34 pm)We are going to setup a sugarcane based Ethanol plant. So, these are very helpful to. us.
Thanks
Rajani Hazarika
Zest Green Energy
Assam
email
zestgreenenergy@gmail.com
siva alluri
(December 29, 2018 - 5:10 pm)Thank you Mr.Rajani Hazarika
Ankit
(March 14, 2019 - 3:24 pm)Send all calculation of meterial balance
Ankit
(March 15, 2019 - 6:43 pm)Send all calculations of grain based distillery
siva alluri
(March 21, 2019 - 3:04 pm)We will provide soon
Harshal
(February 15, 2020 - 4:11 pm)Send all calculation of meterial balance and fermentation calculation
Sanaullah
(April 10, 2019 - 3:33 pm)It’s a good calculation and elaboration on fermentation of various feed stocks.
what should be the optimum mix of secondary mill juice and C molasses for a distillery designed for C molasses?
siva alluri
(April 13, 2019 - 5:32 pm)It is only depended upon total fermentable sugars after mixing the juice and final molasses
VijayKumar Dure
(July 11, 2019 - 2:06 pm)Sirjii pls send including Syrup based example
siva alluri
(July 14, 2019 - 4:57 pm)For syrup also we apply same procedure
According to syrup properties we applied the values ( i.e Brix of the Material , Purity of the material , Reducing Sugars percent (RS) , Un fermentable sugars (UFS) )
Narendra
(August 26, 2022 - 3:10 am)Etheni from ५५ bricks syrup
Shivi
(January 26, 2020 - 3:14 pm)Production of 100 liter ethenol from C heavy molesses ? What is the quantity of molesses are used ethenol fermentation please explain .
siva alluri
(January 26, 2020 - 4:26 pm)Generally yield from C molasses
1 MT of molasses – 240 to 260 liters of ethanol produced ( It is vary according to total reducing sugars in molasses)
arif kazmi
(January 27, 2020 - 6:16 am)Good calculation and and article.
Ankit tyagi
(March 4, 2020 - 8:10 pm)I need all type calculation related distillation and fermentation with how much dosing ppm in fermenter
harihar
(June 16, 2020 - 6:49 am)error in Online Calculator for Yield of Ethanol plz check.
siva alluri
(June 21, 2020 - 10:18 am)Ok corrected
Now it is working
GOVINDAGOUDA PATIL
(June 19, 2020 - 4:26 am)Sir,please provide all material balance calculations and fermentation calculations
siva alluri
(June 21, 2020 - 10:01 am)Ok we will provide soon
ziah
(July 7, 2020 - 2:42 pm)Good day Siva,
Why is the theoretical distillation yield in liters absolute alcohol and not liters?
Sukhraj Soni
(January 16, 2021 - 4:22 am)please provide all material balance calculations and fermentation calculations
V P Rajput
(March 21, 2021 - 11:36 pm)Theoretical ethanol production from sucrose (100 kg) =51.14 / 0.78934 = 65 Liters
Sir I think here term sucrose should be TRS
MOHAMMAD jamal
(April 5, 2021 - 10:32 am)dear siva, i m m.jamal, doing as production manager in a distillery here in pakistan. i do appreciate your article and we ll remain i contact here.
Uttam
(October 13, 2021 - 11:28 am)how to calculate yield of ethanol from syrup
siva alluri
(January 2, 2022 - 8:50 am)Please go through the below link
Click Here for yield of Ethanol
HARSH
(November 19, 2021 - 7:05 am)What Is the B Heavy Molasses Viscosity in Cp? also Brix and Purity for B heavy Molasses.
Mian Azeem Akhtar
(October 10, 2022 - 8:19 am)Very helpful article,
siva alluri
(October 14, 2022 - 5:40 am)Thank you
Mian Azeem Akhtar
(October 10, 2022 - 8:20 am)Very helpful article can you share article on 2nd effect cane juice please