Biofuel from wastes an economic and environmentally feasible resource

DevendraPratap SinghDevendraPratap SinghDepartment Of Applied ChemistryDepartment Of Applied ChemistryDr. Ambedkar Institute Of Technology for HandicappedDr. Ambedkar Institute Of Technology for HandicappedKanpuKanpurr

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CONTENTS

1.Introduction2.Need of Biofuel3.Steps for Production of Biofuel from Lignocellulosic Biomass(a)Pretreatment (Comparative study)(b)Enzymatic hydrolysis & Fermentation(c)Kinetic study of production of ethanol4.Advantage of bioethanol5.Conclusion & Effective parameters6.Major concerns/problems in bio ethanol production from cellulosic materials7.Future Prospectus8.Case Study of total biofuel production

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(a) BIOMASS

Biomass is a renewable energy resource derived from the carbonaceous waste of various human and natural activities.

It is derived from numerous sources, including the by-products from the timber industry, agricultural crops, raw material from the forest, major parts of household waste and wood.

Barley Straw, Rice Straw, Wheat Straw and Rape Straw before Pre-treatment

(1) Introduction

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(b) Biomass Resources

Plantation (Production group)

Untapped Natural Resource

Agriculture, Livestock, Forestry and Fishery group

Other Waste group

Agriculture: Rice husk, Rice straw, Wheat straw, Vegetable residue, etc

Livestock: Animal waste, Butchery waste, etc.

Forestry: Forest residue, Thinned wood, Processing waste, Sawdust, etc.Fishery: Processing waste, Bowel, Dead fish, etc.Industry: Sewage sludge, Organic processing waste, etc.

Household: Garbage, Human waste, etc.

Continental area: Grain, Plant, Vegetable, Fat and oil, etc.

Water area: Algae, Photosynthetic bacteria, etc.

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A fuel that is produced using biological feedstock's. It is a renewable energy source derived from biomass, such as plants, agricultural or forestry waste, animal wastes, or food waste. Common biofuels include ethanol and biodiesel.

(c) BIOFUEL

First generation Biofuels : Corn and sugar to ethanol, Chemical transesterification of vegetable oils

Second Generation Biofuels : Lignocellulose to ethanol Enzymatic bioconversion of Vegetable oil

Third generation Biofuels: Energy crops for bio-alcohol, Algal Ethanol /Biodiesel

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(d)ETHANOL

Produced from hydrolysis of sugar crops, Lignocellulosic biomasses, and fruit and vegetable waste by suitable enzymes or acid followed by fermentation of sugars, starch, cellulose and hemicelluloses using yeast or bacterium. It is used primarily as a supplement to gasoline.

Fermentation is the process by which cells release energy under anaerobic conditions .

(C6H10O5)n Acid Pretreatment n C6H12O6

C12H22O11 + H2O invertase C6H12O6 + C6H12O6

C6H12O6 zymase(Yeast) 2C2H5OH +

2CO26

(e) BIODISELIt is Defined as the mono alkyl ester of long chain fatty acids derived from renewable lipid sources by Transesterification. It is produced from virgin or used vegetable oils (both edible & non edible) and animal fats through various chemical process.

Transesterification: Transesterification is the process of reacting a triglyceride molecule with an excess of alcohol in presence of catalyst to produce glycerin and fatty aids.

Triglyceride + Methanol NaOH or KOH Methyl ester + Glycerol

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It provides a market for excess production of vegetable oils and animal fats.

It decreases the country's dependence on imported petroleum.

It is renewable and does not contribute to global warming due to its closed carbon cycle.

2. Need of Biofuels

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(a) Pretreatment

A pretreatment step is necessary for the enzymatic hydrolysis process. It is able to remove the lignin layer and to decristallize cellulose so that the hydrolytic enzymes can easily access the biopolymers.

Need of lignocellulose pretreatmentTight multi-polymeric complex of cellulose, hemicelluloses and ligninProtective action of ligninCrystalline structure of celluloseLimited surface area for hydrolysisThe purpose of physical pretreatments is the increase of the accessible surface area and the size of pores of cellulose and the decrease of its crystallinity and its polymerization degree.

3. Steps for Production of Biofuel from Lignocellulosic Biomass

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Effect of Pretreatment

Pretreatment gives enzyme accessible substrate

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Wheat bran, sugarcane bagasse, Rice bran and rape straw were used for the treatment process. Before pretreatment these biomasses are reduced in to smaller particles after milling and crushing (particle size <180 μm).

(b) Dilute Acid pre-treatment

For the comparative result equal amount of biomasses were pretreated in two ways one is acid trement where 2-3% acid (H2SO4) was used for

the pre-treatment method. In this content acid soaked biomass slurry was autoclaved at 1210C for 30 minutes. To separate the solid and liquid fraction centrifuge method was used. The dilution and pH was maintained at 5 by adding alkali of centrifuged biomass before fermentation process.

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Different raw materials and their contains after pretreatment

Raw Material Cellulose Hexosans (H) %

Hemicelluloses Pentosans (P)%

Lignin %

Sugarcane bagasse 45 35 15

Wheat straw 30 50 15

Rice straw 32.1 24 18

Rape straw 33.4 30 17

Rice bran 30.4 22 16

Wheat bran 31.3 23 17.5

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Sample Sample-Acid used for Pre-treatment (%)

CelluloseConversion (%)

Available Substrate (%)

S1 0.5 11.8 88.2S2 1.0 12.8 87.2S3 1.5 13.6 86.4S4 2.0 14.2 85.8S5 2.5 15.2 84.8S6 3.0 16.0 84

Effect of acid pretreatment on carbohydrate content of sugarcane baggase

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(c) Enzyme pre-treatment150 g of each biomass were suspended in 500 mL H2O in ratio of 3:10

(w/v) sugarcane bagasse and added of 0.1 mL of α-amylase enzyme. The pH of sample was adjusted at pH 5, 5.5, and 6. The sample was incubated in water bath 100°C for 30 minutes, after that the mixture was applied for second enzymatic treatment (0.2 ml of glucoamylase). Finally, hydrolzsate was pressed through cheese cloth. The amount of reducing sugar in juice was measured.

pH Temperature (°C) Glucose (%)

5 30 23.355.5 30 22.806 30 22.005 40 21.05

5.5 40 19.436 40 18.95

Effect of enzyme pre-treatment methods on glucose content of sugarcane baggase

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From the Table, it is clear that, increasing pH at 400C showed reverse effect on glucose concentration .

(d) FermentationThe pre-treated samples were carried out for fermentation experiments. The yeast S. cerevisiae was used for fermentation. After 3 fermentation days the ethanol content was measured by gas chromatography. S. cerevisiae was also used with Pitchia stipititis for both the fermentation of pentose and hexose. Equal amount of both the yeast and P. Stipititis were taken for the efficient hydrolysis and fermentation of both Pentose's and hexoses sugar present in the hydrolyzed.

Fermentation Medium:- One litre of production medium was prepared according to the requirement of S. cerevisiae, containing 50.0 gL-1glucose, 1.0 gL-1yeast extract, 5.0 gL-1KH2PO4, 2.0 gL-1(NH4)2SO4 and 0.4 gL-

1MgSO4.7H2O. The medium was sterilized and the pH was adjusted to 5.0.

The Preparation of Inoculums:- The micro-organism was cultured in 250 mL Erlenmeyer flasks, containing 100 mL of the (PDA) medium, which has the same composition as the fermentation medium. The Erlenmeyer flask was incubated at 280C for 6 hours on a rotary shaker at 200 rpm.

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26.7525.48

21.1724.28

10

15

20

25

30

35

40

Sugercanebagasse

Rape straw Wheat bran Rice bran

Typpes of biomass

Etha

nol (

%)

Glucose (%)

Ethanol (%) by S. cerevisie

Ethanol (%) by P.Stitipititis andS. cerevisie

Production of Ethanol % (v/v) at 300C and pH 5,from enzyme treated biomass

Biomass (150g) Sugar (%) Ethanol (%) by

S.cerevisiae S.cerevisiae & P. stipititis

Sugarcane bagasse 23.35 19.25 26.75

Wheat Bran 20.74 17.47 21.17

Rape Straw 22.75 18.09 25.48

Rice bran 21.03 17.95 24.28

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SN. Types of biomass samples

Ethanol %(v/v) byS.cerevisiae S.cerevisiae & P. stipititis

1 Sugarcane baggase 24.25 35.382 Wheat Bran 21.47 31.253 Rape Straw 23.95 34.374 Rice bran 23.05 33.98

Production of Ethanol % (v/v) at 300C and pH 5 of acid treated biomass35.38 34.37

31.2533.98

10

15

20

25

30

35

40

Sugercane bagasse Rape straw Wheat bran Rice bran

Typpes of biomass

Glucose (%)

Ethanol (%) by S. cerevisie

Ethanol (%) by P.Stitipititis andS. cerevisie

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* Theoretical yield based on total sugars is 0.511 gg-1

SN. Raw Materials Sugarcane from Bagasse

Rape Straw

Rice bran

Wheat bran

1 Biomass yield YX/S (gg-1) 0.015 0.014 0.040 0.010

2 Ethanol yield YP/S (gg-1) 0.36 0.29 0.33 0.26

3 Final biomass, (gl-1) 1.49 1.32 1.28 0.92

4 Final ethanol (gl-1) 34.6 26.5 31.5 22.9

5 Substrate utilized, (%) 95.90 90.80 93.52 85.42

6 Fermentation efficiency (% of theoretical)

99.01 96.5 89.2 84.6

7 Fermentation time, (h) 24 24 24 24

(e) Observation of Kinetic study of 100 gm sugar

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Fermentation of 100 gl­-1 sugar by yeast (temp 30C, pH5) () total reducing sugars, () ethanol, () biomass.

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Formula used

Specific growth rate (µ) h-1 =

Specific Ethanol productivity (qp) gg-1h-1 =

Specific substrate uptake rate (qs) gg-1h-1 =

Cell Yield, YX/S (gg-1) =

Ethanol Yield, YP/S (gg-1) =

Fermentation Efficiency (%) =

­

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Enzymes that are able to hydrolyze the cellulose (C6 Sugar) and hemicelluloses (C5 sugars) These are:-

Yeast (Saccharomyces cerevisiae ): is able to utilize only hexose.Z. mobilis: has the ability to decompose both hexose and pentoseTrichoderma resei: produces cellulase enzymes needed to convert cellulose and hemicellulose in to sugars .Clostridium thermocellum (C. thermocellum): this bacterium will convert cellulose directly to ethanol, but has some other byproducts that can reduce efficiency during fermentation.Pitchia stipititis : also able to decompose both hexose and pentoseAspergillus Niger: For saccharification of algal biomass. Aspergillus Niger is cellulolytic and amylolytic in nature as it produces cellulases and amylases. Fungi- Saccharomyces cerevisiae (Strain 1), Kluyveromyces marxianus (Strain 2), Candida tropicalis (Strain 3), , a strain of Pitchia (Strain 4) and Candida krusei (Strain 5). Saccharomyces cerevisiae simultaneously combination with Pitchia stipititis and Pitchia tenofiller for the complete fermentation of sugars.

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BIOMASS

ETHANOL

Handling

PretreatmentEnzymaticHydrolysis Fermentation

Distillation

EnzymeProduction

Inoculation

SUGAR & NUTRIENTS

Acid Pretreatment

CELLULOSE

LIGNIN

XYLOSE

(f) Complete process of production of ethanol

Grinding

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Environmental feasibility: Befouled are biodegradable and far less toxic that fossil fuels, Benefit over fossil fuels is the greenhouse gas emissions reduced.

As motor fuel: The principle fuel used as a petrol substitute is bioethanol in terms of E85, E10. The most common blend is 10% ethanol and 90% petrol .Blending bioethanol with petrol will ensure greater fuel security, avoiding heavy reliance on oil producing nations.

Calorific value: Although the Gross calorific value of ethanol is (29,700kj/kg) lower than petrol (48,000kj/kg) and diesel (44,800 kj/kg), yet is less toxic than bothers. Ethanol is a high octane fuel and has replaced lead as an octane enhancer in petrol , also it has low tendency to create knocking in spark engines.

Minimum expenses: The cost of Ethanol production from lignocelluloses is approx Rs.55/- per liter at this time but in a large scale and using modern, techniques it will be minimized.

(4) ADVANTAGES OF BIOETHANOL

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Property Ethanol Petrol DieselComposition, weight %C 52.2 85-88 84-87 H 13.1 12-15 13-16 O 34.7 0 0 Density, kg/m3 794 750 825 Lower heating value, MJ/kg 26.7 42.9 43 Octane number 100 85-90 - Cetane number / n-Heptane 8 5-15 30-40 Rapid vapour pressure (kPa) 15.6 55-103 1.4 Stoichiometric air/fuel ratio, weight 9:1 14:1 16:1 Boiling temperature, °C 78 80-225 188-343 Flash point, closed cup, °C 13 -42 74

Fuel properties of anhydrous ethanol and comparison with petrol and diesel fuel

Sources: JEC, 2005; Joseph, 2007

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75

80

85

90

95

100

105

110

115

120

0 20 40 60 80 100

Volume % Ethanol

Octa

ne N

umbe

r

Research Octane No. Motor Octaane No.

Effects of Blend on Octane Rating

As the ethanol blending (% of ethanol) increases in the gasoline, Octane rating becomes slightly higher. From the figure the Motor Octane number was found maximum for 100% blend, 112. While Research Octane number was found 118 on 100% blending (Bailey and John Russell ). 25

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(a) Effect of sugar concentration: Ethanol Production slightly decreases with increase in sugar concentration . It can be concluded that it is possible to successively use sugarcane bagasse, wheat bran and rape straw for bioethanol. Enzyme treatment at 30ºC and pH 5 is an effective treatment method for converting biomass to glucose.

(b) Effect of temperature: Ethanol production is significantly reduced by

increasing the temperature .

(c) Effect of Ph: In case of different pH ethanol fermentation is more favourable at pH 5-6.

(d) Effect of nutrient supplementation on ethanol production: In order to improve the bio ethanol production nitrogen source in fermentation medium such as NaNO3 , KNO3 enhances the enzymatic growth as well as fermentation.

(e) Effect of Inoculums size: Enzymatic growth and Ethanol production is significantly increases by greater inoculums size.

5- Conclusion & Effective Parameters

The ability to ferment pentose (five-carbon sugars), especially xylose and arabinose, into ethanol is important for the efficiency and economics of the process.

Recently, special microorganisms have been genetically engineered which can ferment these sugars into ethanol with relatively high efficiency.

Formation of inhibitors is also the effective parameter which decreases the ethanol productivity. Inhibitors decreases the enzymatic growth.

Some of the methods which are required to enhance the production of ethanol from biomass are: Evaporation, Extraction with organic solvents and Adsorption on activated charcoal, molecular sieves, Neutralization, Alkaline Detoxification .

6-Major concerns/problems in bio ethanol production from cellulosic materials

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The production of ethanol from lignocellulosic materials can be made cost-effective and done in large scale provided the following conditions are satisfied:

1. Raw materials can be produced insufficiently large amounts and costs of production and collection are acceptable.

2. Pretreatment of lignocellulosic materials is cost-effective.

3. High yields of ethanol from hexoses and pentose's are attainable.

4. Environmental pollution due to the process is minimized.

5. If bio fuels continue their rapid growth around the globe, the impact on the agricultural sector can be significant. Increased jobs and economic development for rural areas in both industrialised and developing countries is one possibility, if governments put the appropriate policies in place and enforce them. The more involved farmers are in the production, processing, and use of bio fuels, the more likely they are to benefit from them.

Future Prospects

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S.N Agricultural Residue

Agricultural area

(In Thousand Hect.)

Biomass(dry

ton/acre/year)

EtOH Yield

(liter/dry ton)

EtOH Yield(liter/acre/year)

1. Wheat Straw 9485 1-3 333 666

2. Rice Straw 4372 3-4 335 1173

3. Barley Straw 58 3-5 345 1380

4.Sugar cane

Bagasse1970 5-6 360 1980

5. Maize Straw 274 3-4 345 1208

6.Rape (Sarson)

Straw622 3-5 355 1180

Total Biomass (Agricultural Residue) and projected biofuel (Ethanol) production upon total Area (In thousand hect.) of main crops in Uttar Pradesh (2012-13).

Biomass data Source: U.P. all agricultural sankhyikiya spatrika

A Case Study

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Benefits of Biofuels:Using alternative energy is better for the

envoirment.Using homegrown energy is better for health.Using Biofuels is better for the (Rural) economy.It makes us less dependent on foreign imports. Private Sector Investments Rural Employment Reduction in Petroleum Imports Energy Security Earnings from Carbon Credits

dr.pratap2012@gmail.com

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REFERENCES1.Glasser WG, Kaar WE, Jain RK, Sealey JE (2000) Isolation options for no cellulosic hetero polysaccharides. Cellulose 7: 299.317.2.Alriksson, B., Sjöde, A., Nilvebrant, N.-O., Jönsson, L.J. (2006), Optimal conditions for alkaline detoxification of dilute-acid lignocellulose hydrolysates. Appl. Biochem. Biotechnol., 130, 599-611.3.Hakan Bayraktar. (2005). “Experimental and theoretical investigation of using gasoline–ethanol blends in spark-ignition engines”, Renewable Energy Vol. 30 pp1733–1747.4.Alfuso S., Auriemma M., Police G. and. Prati M. V, (1993), “The effect of methyl-ester of rapeseed oil on combustion and emissions of DI diesel engines”, SAE Paper 93-2801.5.Peterson C. and Reece D., (1995), “Emissions characteristics of ethyl and methyl ester of rapeseed oil compared with low sulphur diesel control fuel in a chassis dynamometer test of a pickup truck”, Transactions of ASAE, Vol. 39, No.(3), pp.805-816.6.Agarwal A. K. (2007) “Biofuels (alcohols and biodiesel) applications as fuels for internal combustion engines.” Progress in Energy and Combustion Science Vol.33, pp 233–271.7.Murugesan A, Umarani C, Subtamanian R, Nedunchezhian N, (2009). “Bio-diesel as an alternate fuel for diesel engines – a review”, Renew Sustain Energy Rev; Vol.13 No. (3), pp 653-62.8.Alat M. Balat H. A. (2008). “Critical review of bio-diesel as a vehicular fuel”, Energy Converse Manage; Vol.49 No. (10), pp 2727-41.9.Hsieh, W.-D., Chen, R.-H., Wu, T.-L., Lin, T.-H. (2002), Engine performance and pollutant emission of an SI engine using ethanol-gasoline blended fuels, Atmos. Enviro., 36, 403-410.10.Leong, S.H., Muttamara, S., Laortanakul, P. (2002), Applicability of gasoline containing ethanol as Thailand’s alternative fuel to curb toxic VOC pollutants from automobile emission. Atmos. Enviro., 36, 3495-3503.11.Aristidou, A., Penttilä, M. (2000), Metabolic engineering applications to renewable resource utilization. Curr. Opin. Biotechnol., 11, 187-198.12.Hahn-Hägerdal, B., Wahlbom, C.F., Gardonyi, M., Van Zyl, W.H., Cordero Otero, R.R., Jönsson, L.J. (2001), Metabolic engineering of Saccharomyces cerevisiae for xylose utilization. Adv. Biochem. Eng. Biotechnol., 73, 53-84.13.Sonderegger, M., Jeppsson, M., Hahn-Hägerdal, B., Sauer, U. (2004). The molecular basis for anaerobic growth of Saccharomyces cerevisiae on xylose investigated by global gene expression and metabolic flux analysis. Appl. Environ. Microbiol., 70, 2307-2317.14.Khongsay, N.; Laopaiboon, L.; and Laopaiboon. 2010. Growth and Batch Fermentation of Saccharomyces cerevisiae on Sweet Sorghum Stem Juice Under Normal and Very High Gravity Conditions, Biotechnoogy, 2010, ISSN 1682- 296X © 2010 Asian Network for Scientific Information.15.Yoswantana, N. Phuriphipat, P. Treyawutthiwat. P. 2009. Bioethanol Production from Rice Straw. International Conference on Science Technology and Innovation for Sustainable Well-Being (STISWB).16.Thuesombat, P., Thanonkeo, P., Laopaiboon, L., Laopaiboon , P., Yunchalard ,S., Kaewkannetra, P. and Thanonkeo, S., 2007, The Batch Ethanol Fermentation of Jerusalem Artichoke Using Saccharomyces cerevisiae, KMITL Sci. Tech. J. 7, S2, 93-96.17.Yamba, F.D. Wamukwamba, C.K. Matsika, E., and Sangiso, M. 2007. Investigation into the Production and Use of Bioethanol from Sweet Sorghum as an Alternative Fuel. Department of Mechanical Engineering, School of Engineering, University of Zambia, Lusaka.18.Galbe, M., Sassner, P., Wingren, A., Zacchi, G. 1, s.l.: Applied Biochemistry and Biotechnology, 2007, Vol. 124. 1101-1117. Process Engineering Economics of Bioethanol Production.19.Hahn-Hagerdal, B., Galbe, M., Gorwa-Grauslund M.F., Liden, G., Zacchi, G. 12, and s.l.: TRENDS in Biotechnology, 2006, Vol. 24. Bio-ethanol – The fuel of tomorrow from the residues of today.