Wood pellets are created by utilizing any number of wood plants regardless of type to form a solid, uniform wood based mass. The primary source of these pellets is typically sawdust from wood processing centers or specialized farmed trees, though any wood product can be used in any form. Most recycled materials, however, such as particle board, stained or painted wood or other woods contained treated resin are generally considered unsuitable, however, due to the potential for the resins and other treatments contained on the wood producing toxic fumes during the burning process, therefore only freshly processed wood is generally used for the pellet creation process.

Once the base biomass has been gathered the first stage in producing a wood pellet is to feed the biomass into a hammer mill where the mass is rapidly beaten in order to break apart existing fiber chains and create a uniform, dough-like pulp to ensure uniformity throughout each pellet produced. This pulp is then forced through set dies containing any number of small holes, typically 6mm to 8mm in diameter depending on the regulations of the region and the production requirements. This compresses the pellets into a target size and, in the process, also generates heat to aid with the pellet bonding process.

The heat generated from the extreme pressure while pressing the uniform pulp through the dies enables the natural lignin found within all wood to plastify, bonding the residual disconnected fibers with each other to allow solidification into a highly dense solid mass. This bonding process also allows wood pellets to maintain their shape in any number of conditions – even when immersed in water – without the usage of any additional bonding agent such as glue. This allows for a cleaner, more efficient burning of wood pellets as well as ensure healthier emissions wherever they’re used.

While in the past pellet production was fairly limited and unreliable throughout most places in the world due to poorer production processes and supplies this case has changed in recent years as newer production facilities open up around the world, particularly in the UK and throughout Europe. Utilizing a number of different dies in the production line a wide variety of wood biomass can be effectively used simply be adjusting the pressure as it is being forced through the die holes, allowing greater flexibility in processing meaning higher production capability to expand the wood pellet market. This has also helped drive down the costs of wood pellets substantially with European wood pellet prices coming in at lower rates than those found in the United States.

Though the wood pellet production process is fairly simple at heart new processes are being looked into daily to further improve the pellet generation line and allow for even more biomass to be converted into usable fuel. This can help to even further drive down costs associated with wood pellets and allow more usability around the world, creating an effective alternative for fossil fuels as their corresponding price increases dramatically in response to consumer demand and supply shortages.

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