Environmental Life Cycle Implications of Using Bagasse- Deri

Contract No. DE-AC36-99-GO10337

November 2000 NREL/TP-580-28705

Environmental Life Cycle

Implications of Using Bagasse-

Derived Ethanol as a Gasoline

Oxygenate in Mumbai (Bombay)

Kiran L. Kadam

Prepared for the National Energy Technology Laboratory

Pittsburgh, Pennsylvania, USA and

USAID, New Delhi, India

National Renewable Energy Laboratory

1617 Cole Boulevard

Golden, Colorado 80401-3393

Contract No. DE-AC36-99-GO10337

November 2000 NREL/TP-580-28705

Environmental Life Cycle

Implications of Using Bagasse-

Derived Ethanol as a Gasoline

Oxygenate in Mumbai (Bombay)

Kiran L. Kadam

Prepared for the National Energy Technology Laboratory

Pittsburgh, Pennsylvania, USA and

USAID, New Delhi, India

Prepared under Task No. WG88.0101

National Renewable Energy Laboratory

1617 Cole Boulevard

Golden, Colorado 80401-3393

Contract No. DE-AC36-99-GO10337

NOTICE

This report was prepared as an account of work sponsored by an agency of the United States

government. Neither the United States government nor any agency thereof, nor any of their employees,

makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy,

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that its use would not infringe privately owned rights. Reference herein to any specific commercial

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constitute or imply its endorsement, recommendation, or favoring by the United States government or any

agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect

those of the United States government or any agency thereof.

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Contract No. DE-AC36-99-GO10337

TABLE OF CONTENTS Acknowledgments____________________________________________________________vii

Executive Summary___________________________________________________________1

Background______________________________________________________________________1

Study Objective and Results________________________________________________________1

Next Phase of the Project___________________________________________________________2

1

2

3 Introduction_____________________________________________________________3 Project Scope____________________________________________________________3 Sugarcane and Sugar Production____________________________________________4

3.1

3.2

3.3 World Sugar Situation_______________________________________________________4 Sugarcane Production in India________________________________________________4 Sugar Industry in Maharashtra_______________________________________________4

Ethanol Capacity___________________________________________________________8

Bagasse Storage____________________________________________________________8

Related Research___________________________________________________________9

Study Objective____________________________________________________________9

Study Phases_______________________________________________________________9

Life Cycle Assessment Principles______________________________________________9

Methodology______________________________________________________________11 Functional Unit_________________________________________________________________11

Definition of System Boundaries___________________________________________________11

Interpretation: Life Cycle Impact Assessment_________________________________________12 4 Bioethanol Production in Maharashtra_______________________________________7 4.1 4.2 5 Life Cycle Assessment_____________________________________________________9 5.1 5.2 5.3 5.4 5.5 5.5.1 5.5.2

5.5.3

6 Scoping Options and Decisions_____________________________________________12

6.1 6.1.1

6.1.2

6.1.3

6.1.4

6.2.1

6.2.2 Project Parameters________________________________________________________13 General System Boundaries_______________________________________________________Environmental Issues Considered___________________________________________________Geographical Scope_____________________________________________________________Temporal Scope________________________________________________________________13 14 16 17 6.2 Product Parameters________________________________________________________18 Scenarios______________________________________________________________________18

Functional Unit_________________________________________________________________18

6.3

6.4 6.4.1 Process Parameters________________________________________________________19 LCA-Specific Parameters___________________________________________________20 Allocation Rules________________________________________________________________20

Contract No. DE-AC36-99-GO10337

6.5 Summary of Scoping Decisions and Approaches________________________________20

LCA Software_____________________________________________________________21

General Bagasse Data______________________________________________________21

Bagasse Burning___________________________________________________________25

Ethanol Production________________________________________________________25 Enzymatic Process______________________________________________________________26

Two-Stage Dilute Acid Process____________________________________________________28

Data Summary for Bagasse-to-Ethanol Processes______________________________________29 7 Life Cycle Modeling______________________________________________________21 7.1 7.2 7.3 7.4 7.4.1 7.4.2

7.4.3

7.5

7.6

7.7

7.8

7.9

7.10

7.11 Sulfuric Acid Production____________________________________________________29 Ammonia_________________________________________________________________30 Lime_____________________________________________________________________31 Electricity Production______________________________________________________31 Steam Production__________________________________________________________31 Gasoline System___________________________________________________________32 Gasoline and E10 Fuel Combustion___________________________________________32 7.11.1 Tailpipe Emissions______________________________________________________________32

7.11.2 Biomass versus Fossil Fuel CO2____________________________________________________33

8 Data Quality and Sources_________________________________________________34

8.1

8.2 Data Sources______________________________________________________________34 Data Quality______________________________________________________________35

Presentation of Results_____________________________________________________36

Explanation of Negative Flows_______________________________________________36

Hydrocarbon Emission_____________________________________________________36

Time-Space Implications of Emissions_________________________________________36

Life Cycle Energy Balance__________________________________________________36

LCI for Burning versus Diverting Bagasse to Ethanol: Enzyme Process____________38 Resource Depletion______________________________________________________________

Air Pollutants__________________________________________________________________

Waste Generation_______________________________________________________________

Energy Consumption and GHGs____________________________________________________40 40 40 40

49

49

49 49 9 Results and Discussion____________________________________________________36 9.1 9.2 9.3 9.4 9.5 9.6 9.6.1 9.6.2 9.6.3 9.6.4 9.7.1 9.7.2 9.7.3 9.7.4

9.8.1 9.8.2

9.8.3 9.7 LCI for Burning versus Diverting Bagasse to Ethanol: Dilute Acid Process__________48 Resource Depletion______________________________________________________________Air Pollutants__________________________________________________________________Waste Generation_______________________________________________________________Energy Consumption and GHGs____________________________________________________9.8 LCIA for Burning versus Diverting Bagasse to Ethanol__________________________49 Greenhouse Potential____________________________________________________________50 Natural Resource Depletion Potential________________________________________________50

Air Acidification Potential________________________________________________________51

Contract No. DE-AC36-99-GO10337

9.8.4

9.8.5

9.8.6 9.8.7 Eutrophication Potential__________________________________________________________Human Toxicity Potential_________________________________________________________Air Odor Potential_______________________________________________________________

Maximum Incremental Reactivity Potential___________________________________________51 54 54 54

10

11 Conclusion___________________________________________________________56 Next Phase of the Project________________________________________________57

List of Acronyms and Abbreviations_____________________________________________59

References__________________________________________________________________60

Appendix A: Project Review___________________________________________________63

Appendix B: Impact Assessment________________________________________________64

Background_____________________________________________________________________64

Overview of Life Cycle Impact Assessment Indices_____________________________________66 Greenhouse Potential____________________________________________________________________

Acidification Potential___________________________________________________________________

Eutrophication Potential_________________________________________________________________

Natural Resources Depletion Index_________________________________________________________

Human Toxicity Index___________________________________________________________________

Stratospheric Ozone Depletion Index_______________________________________________________66 66 67 68 70 74

Index Calculation________________________________________________________________74 Odor Index____________________________________________________________________________76

Appendix C: List of Alcohol Manufacturers in Maharashtra_________________________78

Contract No. DE-AC36-99-GO10337

vLIST OF TABLES

Table 1. India’s leading sugarcane-producing states_________________________________________________4

Table 2. Comparison of Maharashtra state and Indian national sugar statistics____________________________6

Table 3. Number of sugar mills in India by cane crushing capacity______________________________________6

Table 4. Sugar factories in Maharashtra by geographical region_______________________________________7

Table 5. Data for VSSK Ltd.’s sugar mill in Sangli, Maharashtra_______________________________________7

Table 6. Environmental inventory flows considered_________________________________________________16

Table 7. Equivalency between current gasoline and E10 blend________________________________________18

Table 8. Summary of scoping decisions and approaches_____________________________________________21

Table 9. Proximate chemical composition of bagasse produced in Florida and Hawaii (oven-dry basis)_______22

Table 10. Proximate chemical composition of commercially baled sugarcane bagasse (oven-dry basis)_______23

Table 11. Calorific value and the elemental analysis for bagasse______________________________________24

Table 12. Recent data on bagasse composition____________________________________________________24

Table 13. Changes in bagasse composition due to storage____________________________________________24

Table 14. Data summary for bagasse-to-ethanol processes___________________________________________30

Table 15. Combustion-related properties of green feedstock and ligneous residues________________________30

Table 16. Overall emissions for current gasoline and E10 blend_______________________________________32

Table 17. Overview of change in emissions from low-level and high-level ethanol blends___________________33

Table 18. Apportioned emissions for E10 Blend____________________________________________________34

Table 19. Data sources and quality_____________________________________________________________35

Table 20. Explanation of negative flows__________________________________________________________37

Table 21. Life cycle inventory for burning versus perting bagasse to ethanol: Summary for enzyme process___39

Table 22. Natural gas consumption and CODs for key modules_______________________________________39

Table 23. Life cycle inventory for burning versus perting bagasse to ethanol: Summary for dilute acid process_48

Table 24. Life cycle impact assessment for burning versus perting bagasse to ethanol: Summary for enzyme

process___________________________________________________________________________________50

Table 25. Life cycle impact assessment for burning versus perting bagasse to ethanol: Summary for dilute acid

process___________________________________________________________________________________51

Table 26. Ozone-forming potential of selected compounds___________________________________________54

Table 27. Greenhouse gas potential factors_______________________________________________________66

Table 28. Acidification potential reactions________________________________________________________67

Table 29. Eutrophication potential factors________________________________________________________68

Contract No. DE-AC36-99-GO10337

LIST OF FIGURES

Figure 1. Geographical distribution of sugarcane production in India........................................................................5

Figure 2. Schematic representation of extending system boundaries.........................................................................10

Figure 3. Elements of the scoping phase for life cycle analysis..................................................................................13 Figure 4. General system boundaries for the comparison of burning of excess bagasse versus its persion to ethanol

production...................................................................................................................................................................14

Figure 5. Energy and mass equivalency between current and future scenarios in the context of the functional unit.19

Figure 6. Enzymatic process flow diagram.................................................................................................................26

Figure 7: Two-stage dilute-acid process flow diagram..............................................................................................28

Figure 8. Comparison of burning versus perting bagasse to ethanol: Coal usage..................................................41 Figure 9. Comparison of burning versus perting bagasse to ethanol: Natural gas usage.......................................41

Figure 10. Comparison of burning versus perting bagasse to ethanol: Crude oil usage........................................42

Figure 11. Comparison of burning versus perting bagasse to ethanol: Water usage..............................................42

Figure 12. Comparison of burning versus perting bagasse to ethanol: Carbon monoxide emissions.....................43

Figure 13. Comparison of burning versus perting bagasse to ethanol: Hydrocarbon (except methane) emissions.43

Figure 14. Comparison of burning versus perting bagasse to ethanol: Sulfur oxides (SOx as SO2) emissions.......44 Figure 15. Comparison of burning versus perting bagasse to ethanol: Nitrogen oxides (NOx as NO2) emissions..44

Figure 16. Comparison of burning versus perting bagasse to ethanol: Particulate matter (unspecified) emissions.

....................................................................................................................................................................................45

Figure 17. Comparison of burning versus perting bagasse to ethanol: Lead emissions.........................................45

Figure 18. Comparison of burning versus perting bagasse to ethanol: Fossil CO2 emissions................................46 Figure 19. Comparison of burning versus perting bagasse to ethanol: Methane emissions...................................46

Figure 20. Comparison of burning versus perting bagasse to ethanol: Process energy usage...............................47

Figure 21. Comparison of burning versus perting bagasse to ethanol: Nonrenewable energy usage.....................47

Figure 22. Comparison of burning versus perting bagasse to ethanol: Greenhouse effect potential......................52

Figure 23. Comparison of burning versus perting bagasse to ethanol: Depletion of non-renewable resources.....52

Figure 24. Comparison of burning versus perting bagasse to ethanol: Air acidification potential.........................53 Figure 25. Comparison of burning versus perting bagasse to ethanol: Eutrophication potential...........................53

Figure 26. Comparison of burning versus perting bagasse to ethanol: Human toxicity potential..........................55

Figure 27. Comparison of burning versus perting bagasse to ethanol: Air odor potential.....................................55

Figure 28. Comparison of burning versus perting bagasse to ethanol: EPA-Maximum incremental reactivity

potential......................................................................................................................................................................56

Figure 29. Life cycle impact assessment framework...................................................................................................65

Contract No. DE-AC36-99-GO10337

ACKNOWLEDGMENTS

This work was supported by the National Energy Technology Laboratory, Pittsburgh, PA, USA,

and the U.S. Agency for International Development (USAID), New Delhi, India. The author

wishes to thank these entities for financing the study and members of the Review Committee

(see Appendix A) for their thoughtful review of this report and many useful comments and

suggestions. Vince Camobreco of Ecobalance Inc. and John Sheehan of NREL deserve a special

mention for their help throughout this project.

Contract No. DE-AC36-99-GO10337

EXECUTIVE SUMMARY

Background

Bagasse is the fibrous residue generated during sugar production and can be a desirable

feedstock for fuel ethanol production. About 15%–25% of the bagasse is left after satisfying the

mills’ energy requirements, and this excess bagasse can be used in a bioconvesion process to

make ethanol. It is estimated that a 23 million L/yr (~6 million gal/yr) ethanol facility is feasible

by combining excess bagasse from three sugar mills in Maharashtra state. The annual gasoline

consumption in Mumbai is estimated to be 400–500 million L, and the plant could supply about

half of the ethanol demand, assuming that all gasoline is sold as an E10 fuel, a blend of 90%

gasoline and 10% ethanol by volume.

This study discusses the potential benefits of using bagasse-derived fuel ethanol in India. This

strategy is pertinent to the Indian scene because it can: 1) reduce the net emissions of carbon

dioxide, 2) improve air quality in major metropolitan areas such as Mumbai when used as an

oxygenate additive to gasoline, 3) spur rural economic development, and 4) improve the

country’s energy security by reducing its reliance on foreign oil and associated risks.

Study Objective and Results

The study objective is to conduct a life cycle assessment (LCA) to quantify the environmental

benefits of using bagasse-derived ethanol as a gasoline oxygenate in Mumbai. The LCA results

would serve as a basis for deploying bagasse-to-ethanol production in Maharashtra, because

positive environmental benefits—both in terms of local air quality and climate change—align

with USAID’s mission and objectives.

The LCA performed in this study demonstrates the potentially significant benefits of using

ethanol derived from bagasse in Maharashtra. The overall results revealed a fundamental

difference between Scenario 1 (burning excess bagasse as a disposal option) and Scenario 2

(conversion to ethanol) in terms of energy derived from renewable sources and the concomitant

benefits of reduced greenhouse gas emissions. In particular, lower net values for the ethanol

scenario were observed for the following:

Carbon monoxide

Hydrocarbons (except methane)

SOx and NOx

Particulates

Carbon dioxide and methane

Fossil energy consumption

Hence, implementing the ethanol scenario would reduce air emissions and fossil energy

consumption. Reduced carbon dioxide and methane emissions, although not regulated or

mandated by state or national laws, are also desirable attributes. The lower greenhouse potential

of Scenario 2 can be important if greenhouse gas trading is possible, or in the case of Joint

Contract No. DE-AC36-99-GO10337

Implementation because India is a developing country. Additional drivers are the lower values

observed for the following six impact assessment categories for the ethanol scenario, when

compared to the burning scenario:

Greenhouse potential

Depletion of natural resources

Air acidification potential

Eutrophication potential

Human toxicity potential

Air odor potential

Hence, the ethanol scenario distinguishes itself by demonstrating lower burdens than the burning

scenario for key environmental criteria, both regulated and unregulated.

Next Phase of the Project

The next phase should address how to deploy this option in India by capitalizing on the

environmental benefits of perting the excess bagasse to ethanol production. The action plan

would involve institutional and stakeholder networking and would address deployment this

technology with the help of relevant parties in India, from both the public and private sectors.

Early this year, India’s Minister of Petroleum and Natural Gas approved the use of ethanol as a

fuel/additive. During his recent trip to India, President Clinton signed a joint statement on

cooperation between India and the United States in the areas of energy and environment; the

statement has language about Clean Development Mechanism as specified under the Kyoto

Protocol. Hence, these recent developments in India portend a fertile ground for deploying the

bioethanol option in India.

Contract No. DE-AC36-99-GO10337

1 INTRODUCTION

Worldwide economic development will lead to increased emissions of greenhouse gases (GHGs)

well into the next century. Developing countries like India and China are expected to be major

contributors to atmospheric carbon dioxide (CO2) build-up and are potential targets for the

deployment of biomass-based technologies, given the large amounts of biomass available within

their borders.

India is the world’s sixth largest and second fastest growing producer of greenhouse gases. In

1992, India’s carbon emissions were 177 Mt (million metric tons), the third largest among non-

OECD (Organization for Economic Cooperation and Development) countries. Fossil fuel energy

consumption was about 7.5 quadrillion Btu, 15% of which was attributable to the transportation

sector. About the same fraction of the total carbon emissions was associated with the

transportation sector. Hence, significant carbon emissions arise from the use of fossil fuels for

transportation in India. Vehicular emissions also contribute to local air pollution. Delhi, Mumbai

(formerly Bombay), and Chennai (formerly Madras) are three of the world’s ten most polluted

cities. For the specific case of Mumbai, the National Environmental Engineering Research

Institute in Nagpur, India, estimates that motor vehicles will contribute nearly 90% of the

255,000 t/yr of carbon monoxide (CO) emissions. Oxygenating the gasoline with ethanol can

reduce CO emissions.

This report discusses the potential benefits of using bagasse-derived fuel ethanol, a strategy that

is relevant to India, as it can: 1) reduce the net emissions of CO2 into the atmosphere, 2) improve

air quality in major urban centers such as Mumbai when used as either a 10% (by volume)

oxygenate additive to gasoline (short-term) or as an alternative to gasoline (long-term), 3)

provide rural economic development, and 4) improve the country’s energy security by reducing

its exposure to risks associated with foreign oil.

2 PROJECT SCOPE

The primary objective is to conduct a life cycle assessment (LCA) to quantify the environmental

benefits of using bagasse-derived ethanol as a gasoline oxygenate in Mumbai. The LCA results

will serve as a basis for deploying bagasse-to-ethanol production in Maharashtra, because

positive environmental benefits—both in terms of local air quality and climate change—align

with USAID’s (U.S, Agency for International Development) mission and objectives. A brief

discussion is also provided on how Joint Implementation (JI) and Clean Development

Mechanism (CDM) initiatives and emissions trading, opportunities available to developing

countries under the United Nations Framework Convention on Climate Change, can be used to

help deploy bagasse-to-ethanol production India.

Contract No. DE-AC36-99-GO10337

3 SUGARCANE AND SUGAR PRODUCTION

3.1 World Sugar Situation

Brazil and India are the world’s two largest sugarcane (Saccharum officinarum) growers with

production of 300 and 285 Mt/yr, respectively (Lower and Barros 1999; Singh 2000). These two

countries are also expected to account for nearly 75% of the future increase in sugarcane

production. World sugar consumption in 1999–2000 is estimated at 131.3 Mt, up 2% from the

previous year’s level, with Brazil and India contributing 19.0 and 17.9 Mt, respectively (World

Bank 2000).

3.2 Sugarcane Production in India

As demonstrated in Table 1, India’s leading sugarcane-producing states are Uttar Pradesh,

Maharashtra, and Tamil Nadu, together accounting for about 70% of the national output (Smouse

et al. 1998; Deccan Herald 1999). Although the focus of this study is Maharashtra, similar

ethanol-producing facilities are possible in Uttar Pradesh and Tamil Nadu, and these could

provide ethanol for an E10 blend, respectively, for Delhi and Chennai, the other two Indian cities

to have the dubious distinction of being on the list of the world’s 10 most polluted cities. The

geographical distribution of this important crop for the entire country is shown in Figure 1

(USDA 1998).

Table 1. India’s leading sugarcane-producing states 1998-1999a

% of Production, % of Production, % of

Mt Total Mt Total Mt Total

b NAbTamil b NAb

Estimates.

Not available. b a

3.3 Sugar Industry in Maharashtra

Maharashtra State is a leader in both agriculture and industrial growth in India. As shown in

Table 1, Maharashtra is the second largest sugarcane producing state in India. Typical sugar

industry statistics for Maharashtra are shown below (REPSO 1998).

Annual average cane production: 40–45 Mt

Average sugar recovery: 11.11 Mt

Number of sugar mills: 109 (cooperatives)

A comparison of Maharashtra state with the country as a whole, in terms of key industry

parameters for the last 5 years, is presented in Table 2 (Maharashtra State Govt. 1998). Table 3

Contract No. DE-AC36-99-GO10337

indicates that Maharashtra ranks second in India, based on the number of cane sugar mills

(Maharashtra State Govt. 1998). However, in sugar production, it ranks first and surpasses even

Uttar Pradesh, due to its high yield of sugar per t of cane. Since 1987, a minimum capacity of

2,500 t crushed per day (TPD) has been imposed for new mills, and incentives are in place to

encourage expansion of existing mills to 5,000 TPD (Winrock International 1993). Maharashtra

has 12 and 6 mills with crushing capacities of >3,500 TPD and >5,000 TPD, respectively.

The southern and western Maharashtra regions have a greater share of cooperative sugar

factories in the state. Table 4 offers regional distribution of sugar factories in Maharashtra

(Maharashtra State Govt. 1998).

Figure 1. Geographical distribution of sugarcane production in India.

Contract No. DE-AC36-99-GO10337

Table 2. Comparison of Maharashtra state and Indian national sugar statistics

cultivation,

‘000 ha

production, Mt

Crushing

capacity,

Mt

No. of sugar

mills

Average

recovery, %

cane

Sugar

production, Mt Maharashtra Statea1993-1994-1995-1996-1993-1994-1995-1996-1994 19951996 1997 1994 1995 19961997 (10%) (14%)(14%) (12%) (12%) (16%)(17%) (15%) 24.68 45.9951.47 31.01 130.38 (25%) (31%)(30%) (24%) 97 107109 105 412 (25%) (26%)(26%) (26%) 9.429.90 2.75 (28%) 5.02(34%)5.39 (33%) 3.44 (27%) 12.90

a% numbers in parentheses represent Maharashtra’s contribution to the national statistics.

Table 3. Number of sugar mills in India by cane crushing capacity

Total

Number

of Mills

Number of Mills at Specified Capacities

Uttar Pradesh 36 13 43 7 12 111

17 35 12 109

Andhra Pradesh 20 3 9 1 3 36

Tamil Nadu 5 6 19 2 2 34

7 4 31

10 3 0 29

1 6 2 19

2 11 1 19

2 3 1 11

State TPD <1250 TPD 1250–2500 TPD 2500–3500 TPD 3500–5000 TPD >5000

Contract No. DE-AC36-99-GO10337

Table 4. Sugar factories in Maharashtra by geographical region

Geographical Region Number of Sugar Installed Capacity, Factories TPD

Total cooperatives 81 209,650

South and west 78 204,600

Central 27 51,250

Eastern 19 21,250

Table 5 lists data for Vasantdada Shetkari Sakhar Karkhana Ltd.’s (VSSK) sugar mill in Sangli,

Maharashtra (Winrock International 1993; Smouse et al. 1998). The cane-crushing capacity at

VSSK can be expanded to 7,500 TPD; however, mill management does not plan to expand

beyond 6,000 TPD. This mill is considered as a typical candidate mill pertaining to ethanol

production.

Table 5. Data for VSSK Ltd.’s sugar mill in Sangli, Maharashtra Parameter Value

Mill capacity, TPD 5000

Cane crushed, t/year 924,048

Crop duration, days/year 200

Average cane crushing rate, TPD 4,972

Downtime, % of milling season 19.4

Fiber, % of cane 13.7

Bagasse, % of cane 30.8

Moisture, % of bagasse 50.6

Bagasse produced, t 284,422

4 BIOETHANOL PRODUCTION IN MAHARASHTRA

Bagasse is the fibrous residue left after extraction of sugar from the cane and can be a good

feedstock for bioethanol (i.e., biomass-derived ethanol) production. Bagasse is preferably used

by the sugar mills for steam and power generation to satisfy internal needs; however, about 15%-

25% of the bagasse is left after satisfying the mills’ energy requirements, and this excess is not

burned in the mill boilers. (Steam consumption in Indian sugar mills is as high as 50-55% on

cane compared to 40% in Hawaii. With improvements in or replacement of existing boilers, the

excess bagasse figure could be higher.)

A bagasse-based ethanol project is in the planning/development stage in the United States. BC

International (BCI) is adapting a non-operational molasses-to-ethanol plant in Jennings,

Louisiana, to process local agricultural residue (USDOE 1998). This is a first stand-alone,

commercial, biomass-to-ethanol plant and is expected to produce about 75 million L/yr (20

million gal) of ethanol a year from sugarcane bagasse and rice hulls as feedstock. This project is

proceeding toward commercialization, and being an industrial-scale demonstration of the

biomass-to-ethanol technology, it can be used as a model for a plant in Maharashtra. Such an