Most pellets are made in large production commercial pellet mills but this is starting to change as more consumers and small businesses are taking advantage of small scale pellet mills.
If you are curious about how wood pellets are made or are interested in making them yourself this article will give you a short introduction.
Pellets can be made from many biomass materials.
Pellets were made for animal feed from materials like grain and alfalfa long before manufacturers started making pellets from wood for heating fuel.
The process for making pellets from just about any organic material is basically the same as it is for pelletizing wood.
A pellet is simply a compressed form of the original material.
The material is compressed by pushing it into a funnel shaped die.
As the material goes deeper into the die it compresses as the hole diameter gets smaller.
This also generates heat that will melt binding agents in the material.
When the compressed pellet falls out the other end of the die it cools and the binding agent hardens and acts as a glue that holds the material together as a hard pellet.
The material is pushed into the die by a roller that rolls over the surface of the die.
Some materials will need more conditioning than others before being made into a pellet.
The size must be reduced so it will fit into the dies.
Most materials will need to be dried to the right moisture content which can vary depending on the material.
A binding agent may need to be added but some materials have enough natural binding agent in them.