As with most industries, the development of large scale wood pellet plants currently dominates the wood pellet production market. However, there is a growing number of wood pellet making machines available for even small home owners to use to produce there own pellet fuel. However there is very little information available on which wood pellet making machine is suitable to process different biomass materials for fuel pellets.

Pellet Machine and Pellet Mills and Press

The pellet machine has been an industrial tool for over a hundred years. The first intended use of the pellet machine was to create a superior animal feed. The idea was to process the grasses, straws, vitamins and minerals into pellet form. The advantages of such were that it would be much cheaper to transport the feed, much easier to get the animals to take the required mineral and vitamins and eat the correct amount of food to achieve the best cost to profit ratio. Pellet machines were very successful in the animal feed industry and today, pelleted animal feed in the market leader as a way to control feed to stock animals.

However, the type and design of pellet machine used form making animal feed, is not the same type of pellet machine that can be used for making a wood pellet. Wood as a raw material is very different to straws and grasses. Wood has a much higher density and stronger fibres. These differences mean wood performs very differently in the pellet machine. To compress a material into a pellet requires sufficient temperature and pressure to melt the materials natural lignin. Due to the increased density of wood, means that wood has to reach a higher temperature than grasses and straws to form a pellet. Also, due to the increased density of the wood, more power is needed to compress the wood through the die template in the pellet machine. This generally means the pellet machine needs to be geared down to provide more torque. There are various other changes in design of the pellet machine to compress wood into pellet form.

Wood Pellet Fuel and Pellet Fuel Grades
 

Not all wood pellets are the same, depending on the type of wood residue used to produce the pellets the ash content of the pellets can change. For example, to produce a pellet with as little ash as possible, practically all bark must be removed from the pellets. In many cases though, this is not practical, and also bark contains a lot of energy. However the pellets produced will have a higher ash content, and this may limit the number of pellet stoves and boilers the pellets can be burnt in successfully. Generally pellet stoves and boiler which have a drop down design will not be able to burn the pellets. Therefore it is much better form consumers to avoid this design of pellet burner.

Wood Pellet Manufacturing and Details

When making a wood pellet, before placing the material into the machine, it is very important to monitor the moisture content and make sure it is dry enough but still have enough moisture to melt the natural lignin to help bind the wood pellet together.