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How to Make Wood Pellets

Shah Newaz Alam
The rising cost of wood and carbon based fuels has paved the way for the alternative measure of making low cost fuels, an utmost necessity. Wood pellets can prove to be the solution. The entire heating process becomes even more cost-effective if these pellets can be prepared at home.
Besides being cost-effective, another positive attribute of wood pellets is that they are carbon neutral. The trees from which they are made, absorb the same amount of carbon dioxide as the pellets emit upon burning. Let us see the procedure of making this excellent form of alternative fuels.

Important Requirements for making Wood Pellets

Raw material

Potential materials are not a matter of concern. Any type of wood, both soft and hard, can give excellent results. Remember while selecting the raw material that it needs to be reducible to its granular form.

Equipment

Here is how wood pellets can be made at a household level with a simple small scale mill. Heavy machinery like hammer mills, dryers, pelletizers, coolers, baggers, and boilers are not needed at all. However, if the size of the particles being used as raw material are large, then a small hammer mill to crush the material may be needed.

Steps for making Wood Pellets

Step 1

The dried saw dust, wood shavings, and pieces, need to be gathered first. Any particle that is more than ΒΌ inch in length must be reduced to grains.
This can be done by hammering the particles manually, but for better results it is always preferable to use a hammer mill. The final raw material that will be going through the remainder of the process, should be uniform and in a granular form.

Step 2

The next step is to remove any moisture that may be present in the raw material. The reduced particles are then dried in a dryer at the temperature of 600 degree Fahrenheit. The heating process should be done at a very high pressure.
Wood contains lignin, a natural substance that acts as glue. Since saw dust obtained from wood is used as a raw material, a binding agent to hold the pellets together is not needed.
However, if the amount of lignin in the wood is not sufficient to bind the material, then some external adhesives like cooking oil, vegetable oil, clay, starch, or wax can be mixed with the saw dust, during the heating process.

Step 3

The moisture free substance that is obtained from the drier is then put into the pelletizer which consists of a die and an array of rollers. The rollers force the substance to pass through the die, which gives the pellets a tubular shape. This process is also carried out at a high pressure, to allow the adhesive to just bind the material and not soften it.

Step 4

The pellets obtained from the pelletizer are then cooled down. This is done by putting them in a pelletizer at a temperature of around 5 degree Fahrenheit. Only the hardened and complete ones should be put into the cooler. There should not be any loose dust particles or broken ones.

Step 5

The completely hardened pellets obtained from the cooler are then stored in the containers at a very high pressure. The wood pellets obtained from the cooler contain about 5 to 15% moisture. For better results, the pressure, temperature, and time duration of cooling should be maintained such that the pellets contain only 15% moisture.
The given simple process allows us to get a clean, renewable, and cost-effective form of energy. Wood pellets can be manufactured not only from the wood wastes, but from straw, cardboard, grass, and other plant material. A simple pelletizer, in your possession can save you a load of money from buying fuels.