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Pellet Machine for Wood Chips Not Sawdust – Industrial Engineering Guide

Product Definition

A pellet machine for wood chips not sawdust is an industrial biomass densification system designed to process chipped wood materials through controlled crushing, drying, and high-pressure pelletizing, converting irregular chips into standardized fuel pellets without relying on fine sawdust feedstock.

Technical Parameters and Specifications

Unlike sawdust, wood chips have larger particle size, lower bulk uniformity, and higher moisture variation. A pellet machine for wood chips not sawdust must be integrated with proper pre-processing equipment to ensure stable pellet quality.

Typical industrial configuration:

Production capacity: 1–5 tons/hour per line
Main motor power: 110–315 kW
Die type: Ring die (heavy-duty)
Pellet diameter: 6–10 mm
Raw chip size before crushing: 10–30 mm
Final particle size before pelletizing: ≤4 mm
Moisture before pelletizing: 10%–15%
Final pellet density: 1.1–1.3 t/m³
Bulk density: 650–750 kg/m³
Energy consumption: 80–110 kWh per ton
Compression ratio: 1:6 to 1:8
Die material: Alloy steel, hardness HRC 52–58

Because chips are not uniform like sawdust, crushing precision and moisture control directly affect pellet strength and equipment load.

Structure and Material Composition

A pellet machine for wood chips not sawdust consists of the following assemblies:

Feeding and Metering System
– Variable frequency feeder
– Anti-bridging hopper
– Magnetic separator

Crushing Integration Interface
– Connection to hammer mill discharge
– Buffer bin for material stabilization

Pelletizing Chamber
– Reinforced ring die
– Two or three heavy-duty rollers
– Adjustable roller clearance

Drive and Transmission
– High-efficiency motor (IE3 or IE4 grade)
– Hardened gear transmission
– Safety shear coupling

Lubrication and Cooling
– Automatic lubrication unit
– Bearing temperature sensors
– Forced ventilation cooling

Frame and Base
– Welded carbon steel structure
– Anti-vibration base frame

The reinforced structure ensures stable torque output when processing crushed wood chips instead of fine sawdust.

Manufacturing Process (Engineering Workflow)

Step 1: Raw Wood Chipping
Equipment: Drum chipper
Target size: 10–30 mm chips

Step 2: Fine Crushing
Equipment: Hammer mill
Target size: ≤4 mm
Uniform particle size is critical before feeding into the pellet machine for wood chips not sawdust.

Step 3: Drying
Equipment: Rotary drum dryer
Moisture target: 10%–15%
Excess moisture reduces pellet durability and increases steam formation inside the die.

Step 4: Pelletizing
Equipment: Pellet machine for wood chips not sawdust
Key process controls:
– Stable feed rate
– Die temperature 75–95°C
– Consistent compression pressure

Step 5: Cooling
Equipment: Counter-flow cooler
Objective: Reduce pellet temperature to ambient and stabilize structure.

Step 6: Screening and Packaging
Equipment: Vibrating screen + automatic bagging system

Continuous industrial lines typically operate 16–22 hours per day.

Industry Comparison

Feedstock Type | Pre-Crushing Required | Moisture Sensitivity | Pellet Quality Stability | Energy Demand
Sawdust | No | Medium | High | Medium
Wood Chips | Yes | High | High (after crushing) | Medium–High
Wood Shavings | Partial | Medium | Medium | Medium
Forest Residues | Yes | High | Variable | High

Compared to sawdust systems, a pellet machine for wood chips not sawdust requires additional crushing and stricter process management but allows broader raw material sourcing.

Application Scenarios

Distributors
– Supply pellet fuel to commercial heating markets
– Export pellet production systems to forestry regions

EPC Contractors
– Biomass combined heat and power plants
– Industrial steam boiler fuel preparation lines

Engineering Firms
– Wood processing plant waste recycling
– Forestry residue utilization projects

Using wood chips directly expands sourcing flexibility in sawmills and forest operations.

Core Pain Points and Engineering Solutions

Problem 1: Inconsistent Pellet Density
Cause: Uneven particle size after crushing
Solution: Install high-efficiency hammer mill with proper screen selection.

Problem 2: High Die Wear
Cause: Residual bark and impurities
Solution: Integrate pre-screening and magnetic separation.

Problem 3: High Energy Consumption
Cause: Over-dried or oversized particles
Solution: Maintain moisture at 12–14% and uniform ≤4 mm size.

Problem 4: Low Production Stability
Cause: Feed rate fluctuation
Solution: Use variable frequency feeder and buffer silo.

Problem 5: Pellet Cracking
Cause: Improper cooling process
Solution: Controlled counter-flow cooling with stable airflow.

Risk Warnings and Avoidance Strategies

Risk 1: Skipping Fine Crushing
Directly pelletizing large chips can cause die blockage and overload.

Risk 2: Excess Moisture Variability
Chip storage outdoors may lead to inconsistent moisture levels.

Risk 3: Underestimating Motor Power
Wood chips create higher torque fluctuation than sawdust.

Risk 4: Ignoring Bark Content
High bark ratio increases ash and affects combustion performance.

Procurement Selection Guide

1. Analyze raw wood chip source (species, bark ratio, moisture).
2. Confirm required hourly output capacity.
3. Ensure crushing system can achieve ≤4 mm uniform particles.
4. Verify die compression ratio suitable for wood material.
5. Evaluate motor power with 10–20% safety margin.
6. Assess automation level for moisture and feeding control.
7. Review spare parts availability and die lifespan.
8. Request material testing before final purchase.

Engineering Case Study

Project: Southeast Asia Biomass Fuel Facility
Raw Material: Mixed hardwood chips from sawmill
Capacity: 3 tons/hour

Line Configuration:
Drum chipper → Hammer mill → Rotary dryer → Pellet machine for wood chips not sawdust → Cooler → Screening → Packing

Operating Data:
Final particle size: 3–4 mm
Moisture before pelletizing: 13%
Average output: 2.8–3.1 t/h
Pellet density: 1.2 t/m³
Energy consumption: Approx. 95 kWh per ton

Application: Export-grade wood pellets for industrial boiler clients.
Outcome: Achieved stable production using wood chips as primary feedstock, eliminating dependence on fine sawdust supply.

FAQ

1. Can wood chips be pelletized directly?
   No, fine crushing is required before pelletizing.
2. What is the ideal particle size?
   Generally ≤4 mm.
3. Is ring die recommended?
   Yes, for industrial-scale production.
4. Does bark affect pellet quality?
   Yes, it increases ash content.
5. What moisture is optimal?
   Typically 10–15%, ideally 12–14%.
6. Is additional drying always needed?
   If moisture exceeds 15%, drying is necessary.
7. How does energy consumption compare to sawdust?
   Slightly higher due to crushing requirement.
8. What pellet diameter is standard?
   6–8 mm for fuel markets.
9. Is automatic lubrication important?
   Yes, for continuous industrial operation.
10. Can mixed wood species be processed?
    Yes, with proper blending and moisture control.

Call to Action

For detailed technical specifications, material testing support, layout drawings, or a formal quotation for a pellet machine for wood chips not sawdust, contact our engineering team. We provide capacity planning, process optimization, and commissioning assistance for industrial biomass projects.

E-E-A-T Author Qualification

This document is prepared by a biomass equipment engineer with over 12 years of experience in industrial pellet plant design, focusing on wood residue processing, system integration, and EPC implementation. Data and parameters are based on operational benchmarks from commercial biomass facilities.