Biorefinery Development Using Multiple Feedstocks

March 19, 2009Integrated Biorefinery Platform

Donal F. DayLSU Agricultural Center

DE-FG36-08GO8851(initiated 07/01/2008)

This presentation does not contain any proprietary, confidential, or otherwise restricted information

•Southeast

•Biological Engineering•Food Science•Ag Economics•Extension

•Sugar Station

•This program has been funded and recognized by the DOE

The LSU Agricultural Center is conducting an extensive effort, centered around the Audubon Sugar Institute, to bring biofuels to Louisiana, based

on raw sugar mills as the industrial nuclei.

•Audubon Sugar Inst.

•This project builds upon previous awards.

Overview

• Project start 07/01/2008• Project end 12/31/09• Percent complete 40%

• Barriers addressed– Inadequate Supply Chain– Cost of Production– Process Integration

• Total project funding $1,230,000

– DOE share $984,000 – Contractor share $246,000

• Funding received in FY08$984,000

• Funding for FY09 $0

Timeline

Budget

Barriers

• Interactions/ collaborationsMBI International, Inc.

• Project managementD.F. Day, PI

Partners

Stage• R&D Laboratory to Pilot

Vision- A Biorefinery based around a Raw Sugar Mill

Goal: open opportunity for existing sugar mills to become biorefineries that produce:

Sugar Ethanol ElectricityBy-Products(bioplastic)

SweetSorghum

Feedstocks Transport/harvest Processing

Partial Supply Chain (vision)

$5.00/ton

EnergyCane

Bagasse

Miscanthus

Technical difficulties!

1. Louisiana sugar mills operate only three months of the year

2. As wagonloads of crops are delivered to a processing facility, can the producer and processor rapidly value the convertible ligno-cellulosic content?

3. How long is it practical to stockpile feedstocks?4. What preparation is required prior to pre-treatment?5. What about the waste?

?

1. Louisiana sugar mills operate only three months of the year

Agricultural crops are seasonal, not available year –round

Jan DecJune SeptMarch

Alternative grassy feedstocks, with differing harvest times mayExtend processing season to 9 months, requiring minimum storage of feedstocks.

? Are these viable feedstocks

Approach

Are these Viable Feedstocks?

A. Can these feedstocks be handled within normal milling operations?

B. What is the partition of sugars (simple and complex) between juice and biomass?

C. Can the biomass residues be used as fuel?

D. How does each biomass react to alkaline pretreatment?

B. Crop Partition(biomass)

• Energy cane- nd• Miscanthus- nd• Bagasse*- 200 lbs/ton of sugarcane• Sweet Sorghum* – 200 lbs/ton of s. sorghum

• *wet basis 50% moisture

Sweet Sorghum Partition

for Bio-ethanol Seed heads(7.5%)*

Leaves(18.9%)

Stalk(73.7%)

Grains(2.3%)

Bagasse(16.9%)

Juice(56.8%)

Bio-ethanolBio-ethanol

Sweet sorghum

Milling

Pretreatment

Hydrolysis/Fermentation

% in total (wet basis)

Distillation

Brix (⁰) Sucrose (%) Glucose (%) Fructose (%)

Sweet Sorghum*

13.9 ±0.84 7.9 ±1.39 3.3 ±0.66 1.6 ±0.38

Sugarcane**

Energy cane***

14.5 ±0.2

13.1±0.72

12.7 ±0.3

9.8±0.74

0.33 ±0.01

0.69±0.21

0.30 ±0.02

0.86±0.26

Juice Compositions

•* Milled three times by a pilot scale mill located at ASI, no imbibition.•* *Data from ASI 2007 Juice Survey•*** n=9

Ethanol Conversion from fermentable sugar (sweet sorghum)

Time (hr)

0 5 10 15 20 25 30

% C

on

ce

ntr

ati

on

(w

/v)

0

2

4

6

8

10

12

14

Total sugarsEthanol

Glucan Xylan Arabinan Mannan Lignin Ash

Sweet Sorghum

Seed heads

85.7 nd nd nd 12.64 1.38

Leaf 41.85 25.76 4.17 0 22.07 1.95

Fiber 37.5±11.9 19.7±6.3 3.6±0.3 2.4±1.5 18.4±0.8 0.7±0.2

Sugarcane Bagasse 40.2±3 21.5±3 1.8±0.5 0.4±0.4 24.2±4 4.0±0.5

Biomass Chemical Composition(g/100 g dry matter)

Bio-ethanol Yields &Fermentable Sugars from 1 kg Crop

Weight (g) Ethanol (g) Fermentable sugars (w/w)

Treated Bagasse 68.14* 16.33 Cellulose 49.63%

Treated Leaves 67.15* 12.27 Cellulose 41.59%

Grains 31.51* 13.07 Starch 85.67%

Juice 568** 46.03 Sugars 12.8%

*Dry basis** Wet basis

Ethanol yields/ ton crop(wet basis)

Juice Biomass Total(lbs)

S. sorghum 102 93 195

Energy cane

Miscanthus

Bagasse 0 178 178

C. Can the biomass be used as fuel?

• Cane sugar mills are biomass powered. Combustion analysis needs be conducted on each “bagasse” from each crop, as it would be obtained after passing through a milling tandem.

Approach• Bomb calorimetry and moisture analysis will be

used to determine the BTU value of each biomass. – Not complete

D. How does each biomass react to alkaline pretreatment?

Approach– For each biomass; dilute ammonia pretreat

(under conditions determined for bagasse), enzyme hydrolyze and ferment

– For each biomass; determine optimum AFEX (MBI), enzyme hydrolysis and fermentation conditions

Bagasse response to alkaline pretreatment

Crop AFEX Lime dil Ammonia Untreated

Bagasse 82 85 89 7.4

Sweet sorghum nd 90 64 5.4

Energy Cane

Miscanthus

% enzymatic cellulose conversion

2. How can the producer and processor rapidly value the convertible ligno-cellulosic content?

Near-Infrared Spectroscopy (NIR) is used in Australia to monitor sugar content in sugarcane as it is delivered to the mill. Can this be used to value not only sugars but cellulose in a crop? A spectra-cane NIR is available andwill be used. Spectra-will be calibratedagainst NIST procedures for eachbiomass and HPLC for sugars.

Spectra obtained for energy cane, composition

analysis underway

Approach

3. How do these materials store?

% Loss/month

Bagasse 6.5

Sorghum nd

E. cane nd

Miscanthus nd

Feedstock LossOn Storage

4. What is the preparation prior to pre-treatment?

5. What about the waste?

• Approach: Using an anaerobic digester, treat wastes from pretreatment and fermentation to determine if methane is a viable by-product.

• In progress

Sweet sorghum

Energy Cane

Miscanthus

Juice

BiomassProgress

Future Work- sorghum

– The NIR data on sorghum is incomplete due to disruption by Hurricane Gustav, it will have to be completed this season

– Given results with sorghum grains it is possible that grain sorghum, should be considered as a biofuel crop. This will be investigated.

Future work-energy cane, Miscanthus

• The proposed research components of this grant are yet to be completed. Energy cane research is on going. Miscanthus work cannot start until April when crops are available.

• Upon completion of this program an economic analysis must be conducted.

Success Factors and Challenges

• The current conditions in Louisiana are favorable for raw sugar mills to expand their product line, with mills opting to put in electricity generation. This opens the window for longer operating seasons where significant revenue can be generated by operating in peak electric utilization periods (June-Sept in Louisiana). Which means the mills must operate through this period, with ethanol production becoming a means to keep the factory operating.

• The major challenges is to demonstrate profitability of this approach to both farmer and miller.

Summary

• An integrated approach is necessary to convince all stakeholders that biofuel production at the raw sugar mill is both feasible and profitable.