What are the key temperature phases during biomass pellet production in a Ring Die Pellet Mill?





Ring Die Pellet Mill at different phases for achieving optimal compression, density, GCV, moisture, and durability:



These parameters ensure a balance between temperature, compression, and pellet quality for producing high GCV, low moisture, and durable pellets.





Ring Die Pellet Mill at different phases for achieving optimal compression, density, GCV, moisture, and durability:


1. Temperature Phases in Pellet Formation

• First Phase (70°C):

o Purpose: At this stage, the temperature is moderate as the raw material is still in the initial stage of compression.

o Compression: Low to moderate pressure helps in forming the pellets while maintaining structural integrity.

o Moisture Content: Evaporation starts, and moisture gradually reduces to an optimal level.

o Pellet Density: The pellet density begins to increase as the material is compacted in the die holes.

o Durability: Initial binding starts to form, but the pellet is still fragile.


• Full Flange Operation (92°C):

o Purpose: This is when the pellet mill is running at full capacity, ensuring complete formation of pellets.

o Compression: High pressure ensures the pellets are fully compacted for optimal density and hardness.

o Moisture Content: The majority of moisture is driven out, achieving the desired level (typically around 8-12%).

o Pellet Density: Achieves a higher and more uniform density. Proper compression leads to the necessary mechanical strength.

o Durability: The pellets attain a firm structure, making them more resistant to handling and transportation wear.

o Gross Calorific Value (GCV): The compression at high temperature leads to lower volatile content, enhancing the GCV of the pellets.


2. Key Points to Monitor:

• Compression Pressure: Adequate pressure needs to be maintained to ensure the pellets are properly formed and dense.

• Moisture Content: Check moisture regularly to ensure it is within the optimal range for ideal pellet formation (8-12% for biomass).

• Temperature Control: Monitor the temperature as pellets exit the die. Excessively high temperatures (>100°C) may degrade the pellet quality.

• Pellet Density: Aim for high-density pellets (~650-700 kg/m³) for good mechanical durability and energy content.

• Durability Testing: Conduct water durability tests to confirm that pellets hold together well under stress.


3. Effects on Final Pellet Quality:

• Higher Temperature (>92°C): Increases pellet durability and density, ensuring high GCV.

• Too Low Temperature (<70°C): Results in lower density, poor pellet durability, and higher moisture retention.

• Durability Target: The pellets should resist disintegration for at least 2-3 minutes in water for high durability ratings.


4. Factors Affecting Pellet Quality:

• Raw Material Moisture: Should be properly controlled before feeding into the pellet mill (12-15% ideal).

• Die Hole Size: Affects pellet compression and density.

• Binder Usage: Helps in enhancing pellet durability if natural lignin content in biomass is insufficient.


The above test and results were conducted by PelletIndia.com, ensuring optimal conditions for achieving high-quality biomass pellets with perfect compression, density, GCV, moisture content, and durability during the production process in a Ring Die Pellet Mill.


These parameters ensure a balance between temperature, compression, and pellet quality for producing high GCV, low moisture, and durable pellets. If you need further technical details, feel free to reach out!