Agri-Tech Producers, LLC

Using Torrefied Wood as a Coal Replacement, for

Superior Pellets and Cellulosic Ethanol

Production BY

Torrefaction: A Technology to Densify & Enhance Biomass

– Untreated biomass may be 50% water, it’s bulky and it’s not the most efficient or useable fuel or bio-feedstock. Torrefaction:• Drives off most of the water• Reduces the bulk• Makes a better co-fire fuel to burn with coal• Makes superior briquettes and pellets

– Torrefaction, applied at or near the point of harvest:• Reduces transportation costs of biomass,

per BTU• Produces a more valuable biomass shipment

Torrefaction: Adding Value and Reducing Transportation

Cost/BTU

• Untreated Biomass:– Bulky– Moist– Fibrous– Perishable– Waste– Expensive to

transport

• Torrefied Biomass::

– Dense, If Pelletized, Etc.

– Dry & Water Resistant– Easily Crushed– Does Not Rot– Valuable Fuel– Energy Dense

The Process of Torrefaction

• Heating (300-400º C) wood, in a low-oxygen environment, liberates water, volatile organic compounds (VOC’s), and hemicellulose (HC) from the cellulose and lignin.

• The VOC’s and HC are combusted to generate 80% of the torrefaction process heat.

• The remaining and warm lignin acts as a binder when the torrefied wood is pelletized.

• Torrefied wood can easily replace coal in combustion or be a feedstock for further pyrolysis or gasification for combined heat and power or Fischer-Tropsch liquids.

Schematic of Torrefaction Machine

Higher Heating Value of Torrefied Wood, Charcoal and Coal:Color Approximately Indicates Heating Value

8,458 8,805 9,060 9,248 9,502

11,633

13,471

12,000

-

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

Lightest Lighter Light Dark Darker Darkest Charcoal Coal

BT

U/lb

.Higher Heating Value of Torrefied Wood,

Charcoal and Coal: Color Approximately Indicates Heating

Value

Chemistry of Torrefaction

• At torrefaction temperatures, hemicellulose is the primary wood polymer that is degraded into:

– Permanent gases include H2, CH4, aromatics, CO, CO2, CxHy

– Condensable liquids include acids, ketones, furans, alcohols, terpenes, phenols, waxes, tanins, water

– Solids include char, new and existing sugar structures and new polymers and ash.

• All of the wood polymers undergo dehydration reactions that destroy –OH groups that are responsible for hydrogen bonding with water: this severely reduces the tendency of densified torrefied wood to absorb water.

Mass and Energy Balance of Torrefaction

• Published results indicate mass and energy balance of .8 and .9 respectively (for dry wood).

• This is consistent with the loss of the lower energy VOC and hemicellulose and retention of higher energy lignin and cellulose.

• Assuming – 50% MC wood, – HHV of 8700 Btu/lb for dry wood, – 1000 Btu/lb latent heat of water,– .4 Btu specific heat for wood and 1 Btu specific heat for

water, – Starting temperature of 75 F and exit temperatures of 500°

F.

• ~800 Btu used in processing, this energy is approximately equal to that of the VOC’s and hemicellulose.

• ~3575 Btu left in remaining torrefied product, which weighs ~.33 lbs, for a HHV of 10,800 Btu/lb.

Making Electricity With Torrefied Wood

• Torrefied wood is a much better fuel for co-firing with coal than untreated wood.

• Torrefied wood can be ground to a particle size, similar to that of pulverized coal, with the same or less energy use.

• Untreated wood requires many times the energy use, in grinding (by a factor of 7.5 to 15), to achieve a similar particle size.

Pelletizing & Briquetting Torrefied Wood

• At torrefaction temperatures, the lignin in wood becomes plastic and can actually become a binder of individual wood particles.

• Pellets made from torrefied wood may withstand 1.5 to 2 times the crushing force of normal wood pellets.

• Torrefied pellets show little water uptake on immersion (7-20% of mass), unlike normal pellets.

• University research in the 1930’s and 1940’s details benefits of torrefied wood pellets.

Density of Various Biomass Fuels

Fuel BTU/ lb

Density

lbs/ ft3Specific Gravity BTU/ ft3

Green Wood Chips 4,500 21.29 0.341 95,804

Wood Pellets 7,300 40.00 0.641 292,000

Torrefied Wood 11,000 12.57 0.202 138,314

Pulverized Torrefied Wood 11,000 23.69 0.380 260,545

Pelletized Torrefied Wood (sample) 11,000 28.41 0.455 312,456

Pelletized Torrefied Wood (Bergman) 8,545 46.82 0.750 400,085

Baled Corn Stover (25% MC) 6,076 9.38 0.150 56,961

Baled Switchgrass (15% MC) 6,722 7.43 0.119 49,940

Fuel Cost per MMBtu Electricity by Distance to Plant

$5.00

$7.00

$9.00

$11.00

$13.00

$15.00

$17.00

0 20 40 60 80 100

Miles

$/M

MB

tu E

Coal ($90/ton) Coal ($75/ton) Coal ($60/ton)

Green Wood Torrefied Wood

Delivered Cost per MM Btu Electricity

by Distance to Customer

ATP’s Partner: Kusters Zima Corporation101 Zima Park Drive / I-85 Business

Spartanburg, S.C. 29301Tel: (864) 576-0660

8.74 Acres (35,362 Sq. Meters)

Building Constructed in 1969

80,128 Total Manufacturing Sq. Ft. (7,444 Sq. Meters)

Kusters Zima has over 40 years experience in engineering and

manufacturing machinery for many various industries.

Complete Manufacturing

• Water & Waste Water Equipment

Grit Removal & WashingCourse & Fine Screenings

ClassifiersCSO ScreensDewatering

• Carpet & Textile EquipmentContinuous Preparation

Dye Washers & Scour RangesSteamers

Liquid DispensingWater & Dry Lint Removal Systems

• Contract SalesPiece Parts & Components

Customer Specific Design & BuildBuild to Print

• Complete Metal Fabrication including Welding, Cutting, Forming and Piping.

• Machining Capabilities that include CNC Turning and Vertical Milling Centers.

• Complete Mechanical and Electrical Engineering with the latest Software Versions of SolidWorks and AutoCad.

• Complete Mechanical and Electrical Assembly and F.A.T. for Production Machines and Prototypes.

• Installation and Start-up Supervision.

ATP Resource: Mid-South Engineering

Hot Springs, Arkansas - USA1658 Malvern AvenueHot Springs, AR 71901

PH: 501-321-2276

Complete Engineering Services

Production Process DevelopmentProcess Conceptual DesignProcess Control Drawings

Energy Conservation & Conversion Systems

Civil Engineering ServicesSite Evaluation

Grading & Drainage PlansRoad & Railway Layouts

Structural Engineering ServicesEquipment Foundations

Building Foundations and StructuresMachinery/Equipment Supports

Fall Protection Systems

Mechanical Engineering ServicesCustom Equipment Design

Process Heating & Cooling Systems DesignPiping Systems

Equipment Specifications

Electrical Engineering ServicesPower Distribution System Design

Control System DesignLighting & Grounding Systems

Communication SystemsElectrical Power System Studies

Arc Flash Studies

Project Management ServicesProject Management

Project SchedulingContract and Invoice Administration

Construction ServicesTurnkey Construction

Construction ManagementStart-up Services

Safety Coordination

Helping manufacturers of pellets, briquettes, and other biomass

products improve existing facilities or design and construct new facilities to

meet the growing demand for renewable energy products.

Cary, North Carolina - USA1149 Executive Circle, Suite A

Cary, NC 27511PH: 919-481-1084

Visit us at www.mseco.com

We have over 40 years of experience in designing structural, mechanical, and electrical systems for major industrial

facilities throughout North America and other locations around the world.

Agri-Tech Producers, LLC

Using Torrefied Wood as a Coal Replacement, for

Superior Pellets and Cellulosic Ethanol Production