To make high quality wood pellets, it must be noted, is a process that does not require just the purchase of one pellet machine, rather it requires a complete wood pelletization system.
0-1 Ton Wood Pellet Plant Design
In the system of wood pellets production, feedstock control is extremely important in ensuring that the production operation is successful. The feedstock control process comprises of two stages.
In this stage of production, consistency of the wood being used must be maintained. This means that all the wood that will be used must be of the same species, type and must have grown in the same are, it also means that all he wood must have been subjected to similar production processes previously, just to name afew things that must be similar. To ensure consistency, one might apply one of the following methods: the initial purchasing control may be applied and/ or blending the feedstock that is received in the same manner. This could be as simple as mixing the feedstock received constantly on a pad with a receiving front end loader.
Producers that have a wide range of wood being received could decide to sore the different woods in separate bins. After separatestorage they will then calculate the appropriate percentage of the wood to blend and mix before reaching the process of drying the final grind.
In the second phase, the process involves maintaining he moisture at the correct levels of 10% +/- 1 %. Many producers have had a hug problem controlling this moisture because they either could notaccept it is the required degree or did not know how to maintain it.
From the second phase, it is gathered that when the waste wood is received, its initial moisture is what sets off he system requirements.
Feedstock that is too dry- when the wood waste received is too dry, it must have water added to it before the final grinding process. This ensures that the water will effectively wet the wood. By adding water, the lignin gets to absorb enough water \before the wood gets to the pellet machine. For the lignin to absorb enough water, it will take a while as they are hydrophobic and once they lose water, getting it back into them can be somewhat difficult.
Pre dried feedstock- Most planer shavings are received with the correct amount of moisture because moisture control was done to ensure that the function of the planners is effective. Since they have the correct range of moisture range because of the nature that they are received, before pelleting, they go directly to thehammermill for the final grind.
Greenwood (wood waste that has not been dried)- First is to hog the wood waste so it can be the appropriate size for dryer in feed. To minimize the costs of drying, drying is done using a rotary drum dryer where a small portion of the wood being dried will be used for fuel.
In the stock bin mounted above the final grind is where the moisture word is normally received above he final grind hammermill. To remove metals that still remain in the flow, the hammermill should have a magnetic protection.