Novozymes in brief

Two different pathways:

1. Large scale cassava focused production systems like in Asia producing ethanol for use a e.g. transport fuel

2. Small scale – e.g. integrated agro-forestry systems producing ethanol for use in cook-stoves, as well as misc. food, feed and other energy products

Cassava based ethanol in an African context

1. Reduce deforestation due to charcoal production

2. Reduce accidents and negative health effects relating to indoor use of kerosene, wood or charcoal

3. Improve access to affordable energy

4. Stimulate local agriculture through smallholder/outgrower schemes

Benefits of small scale agro-forestry systems producing ethanol to replace charcoal

• 100% family sector growers– Agro-forestry systems– Degraded & abandoned plots– Diverse mix of trees and crops– Increased food quantity and quality– Raw materials for energy products

• Community pre-processing centres – Buying, training, technical assistance, pre-

processing, storage, logistics• Fruit & Veg consumed locally• Cassava dried chips• Oilseeds raw plant oil• Beans dried & packed for cities• Waste animal feed and biofertilizer

• BioProcessing Centre– Production of ethanol

• Household cooking fuel– Production of Pure Plant Oil

• Diesel substitute in converted generators

• Cookstove Manufacturing Facility

5

Outline of a potential smallholder/outgrower based system

Smallholder agro-forestry concept with integrated food, feed and fuel production

The Fuel Ethanol Process

Raw Materials for Ethanol Production

• Ethanol can be fermented from sugars

• Sugars can be produced by enzymes from starchy raw materials

• Starchy raw materials can be any cereal grains or starchy plant roots

• Examples:

• Corn, wheat, millet, sorghum, rye, barley, rice, cassava

Starch in cassava

Protein middle lamella

Outer wall(-Glucan and pentosan)

Inner cell wall (-Glucan)

Starch granules

Protein matrix

General overview of starch conversion to ethanol

3 types of enzymes required

1. Viscosity reducing enzymes– Viscozyme Cassava R

– Viscozyme cassava C

2. Alpha-Amylase– Liquozyme SC, SC DS and 4X

3. Gluco-Amylase– Spirizyme Fuel

– Spirizyme Ultra

– Spirizyme Excel

Three stages where enzymes are added

Milling /Slurry make up Cooking Fermentation

Type of enzyme added

Viscosity reducing enzyme Alpha-Amylase Gluco-Amylase

Enzyme name

1. Viscozyme cassava R2. Viscozyme cassava C

1. Liquozyme SC2. Liquozyme SCDS

1. Spirizyme fuel2. Spirizyme ultra3. Spirizyme Excel

Main Purpose

Reduce viscosity due to non starch polymers

1. Reduce viscosity due to starch polymers

2. Converts starch to dextrin

To convert dextrin to glucose

Other Benefits

1. Enable mash to be pumped2. Avoids gel formation3. Lower heating and cooling cost

1. Processes starch to be suitable for fermentation

2. Enables better mixing of enzymes3. Avoids gel formation

Enables yeast to consume the glucose and generate ethanol

Working Temp

50-55°C 84-86°C 32-35°C

Ethanol yield from starch: Cassava example

  Yields from 1 ton raw material  

 Cassava Roots Chips Starch

% Starch 25 65 85

100% theoretical      

Ethanol, litres 180 468 612

93% efficiency      

Ethanol, litres 167 435 569

Milling & Cook: Slurry formation and initial breakdown of starch

1. Grind cassava into smaller particles (flour)– Increase surface area (accessibility to the enzyme)

2. Mix flour with water to form a slurry – Form a uniform mixture– Add enzymes to reduce viscosity – Add enzymes to start transformation of flour into dextrin

3. Cook slurry at high temperature use jet or steam– Flour absorbs the hot water and becomes “mash”– Mash becomes thick (viscous) – becomes gelatinized

4. Hold at temperature – Allow time for enzymes to break starch into short chain dextrins

Initial breakdown of starch into shorter dextrin chains

Alpha-Amylase enzyme randomly cleaves large chain dextrins into a mixture of shorter chain dextrins

Alpha-amylase

Shorter dextrin chains

Large Dextrin chains

DP6DP4DP3DP2

Further breakdown of dextrins into fermentable sugars: Two main process options

• Pre-fermentation saccharification– Pre-fermentation saccharification in separate tank for a few

hours at optimal conditions

• Simultaneous saccharification and fermentation– Sugars are generated with the yeast present

– Occurs at typical fermentation conditions

Saccharification: Breakdown of dextrins into glucose

What does Gluco-Amylase do?

Gluco-Amylase breaks short chain dextrins into simple fermentable sugars that yeast can convert into ethanol

Long chain sugarsLong chain sugars(Dextrins)(Dextrins)

SimpleSimplesugarssugars

Typical cost breakdown for cassava-based ethanol production – example from Asia

How Novozymes can assist you

• Provide enzymes solutions designed for starchy raw materials – and including for cassava

• Share our vast global process experience with our customers

• Continuously develop new enzymes and process technologies

Thank Youfor your attention

Please visit our website

www.bioenergy.novozymes.com

Technical service contact: HXL@novozymes.com