APPLICATION NOTES

BIOMASS

RAW MATERIALS

MEASURED CONSTITUENT ENVIRONMENTS PROCESS

LOCATIONSTARGET MOISTURE

PERCENTAGEFINISHED

MATERIALSHog Fuel

Micro ChipsSawdustLumber

MoistureHigh Temperature

DustyBelt Conveyor

Screw Conveyor

Before dryer: < 15%*

After dryer: < 8%*

Wood PelletsPellet Fuel

WHY MEASURE PELLET MOISTURE?The moisture level in woody material in pellet production is critial to meet end-product quality and profit goals. Pellets that are too wwet can result in incomplete combustion, leading to heating instability. Additionally, stored pellets with a high moisture content can cause microbiological activity, which can lead to sponstaneous combustion in silos. Overdried pellets are also vulnerable because they become fragile, compromising integrity and finished product quality. Unmonitored drying leads to increased energy consumption.

TYPICAL PELLET PRODUCTION PROCESSRaw Material Delivery - Large batches of raw materials varying from sawdust, wood chips, hog fuel, micro chips, lumber and trees unsuitable for lumber. This feedstock may be freshly cut, partially dry, or kiln dried. Some manufacturers use sifters or separators to remove non-wood materials such as metal, plastics or rocks.

Chipper - A chipping machine breaks down large non-uniform wood pieces into smaller wood pieces.

Hammermill - Hammermills grind wood pieces into consistent small pieces. These micro chips (3mm) could have wide and inconsistent moisture content ranges.

Dryer - Large high-heat dryer drums, convection ovens, or air blowers dry the sawdust to a consistent moisture level, usually less than 15 percent.

Pellet Mill - The dried sawdust is pressed through heated pellet dies at high pressure. The naturally present lignin, a complex organic polymer, acts as a glue to hold the pellet together.

Cooling - Now hot and soft, pellets must be cooled and dried, usually with blown air. The finished materials moisture content should be no higher than eight percent.

Storage or Packaging - Cooled, dry pellets are stored in silos for bulk shipping or bagged for immediate distribution. *Typical measurements, subject to change per manufacturer’s requirement

SENSORTECH RECOMMENDATIONS

NIR-6000 Industrial-Grade Moisture Analyzer

Location Recommendation: ● After drying process● Mounted to belt or screw conveyor

Process Control: The detected moisture value can be transmitted to your PLC, then programmed to adjust the speed of the dryer conveyor.

Benefits:● Controlled drying process to meet

optimal finished pellet quality

● Lowered energy costs

● Reduced waste

● Safer silo storage

● Package weight targets met

● Improved ongoing profit margins

Sensortech Systems, Inc . sensortech.com info@sensortech.com (805) 981-3735

Wood Pellets Moisture Measurement & Control

Sensortech Systems, Inc . ® sensortech.com info@sensortech.com (805) 981-3735

SPECIFICATIONSRanges and Absolute Accuracy1:

Moisture 0 to 95% ±0.10%

Instrument Repeatability2: ±0.10

Recommended Measurement Distance:

4 -12 in (100-300 mm)

Standard Instrument Weight3: 18 lbs (9.53 kg)

Optical Sampling Size: 1.77 in (45 mm)

Operating Temperatures4:

Standard 32 to 131°F (0 to 55°C)

Air Cooling Panel 32 to 185°F (0 to 85°C)

Water Cooling Panel 32 to 185°F (0 to 85°C)

Heating Option -4 to 131°F (-20 to 105°C)

Enclosure: Cast Aluminum – Powder Coated

Power: 80/265 VAC (50/60 Hz)

Optional 24 VDC

Standard Instrument I/O:

3 self-powered isolated 4-20mA Outputs

Ethernet TCP/IP

Digital RS-485 or RS-422

1 Digital Input

1 Digital Output

Proprietary Interface Options:5

PROFIBUS

PROFINET

DeviceNet

EtherNet

Warranty: 2-year Parts and Labor

Lamp and Motor (5 years)

1 All accuracies subject to application.2 Instrument repeatability is subject to application3 Non-standard enclosures are subject to application4 Several options are available spanning and exceeding the minimum and maximum stated temperature specifications; contact Sensortech for details5 External devices communicate via Modbus/RTU Protocol

The NIR-6000 provides an on-line, real-time moisture analysis of biomass from raw materials through the pelletizing process. This ongoing monitoring enables forward thinking and determination of optimum drying process conditions, essential for biomass manufacturing. Our sensor employs near infrared reflectance (NIR) technology, which is continuous and non-contact.

SENSORTECH SYSTEMS, INC. is a full design, development and manufacturing company specializing in moisture

measurement technology. Our instruments support diverse industries throughout the world and we develop solutions for a comprehensive range of applications.

More Control with Management SoftwareThe NIR Series includes a proprietary PC-based software package that offers an accelerated view of your production process from your process computer or the optional HMI. Features include moisture display, data-logging, calibration utilities and all configuration settings.

®

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are registered trademarks of Sensortech Systems Inc.18-05-002

NIR-6000 Industrial-Grade Moisture Analyzer