No matter you are going to buy wood pellets for your pellet stoves or you are determined to buy a pellet mill to make wood pellets by yourself, it’s essentially important for you to know how to tell a good quality wood pellet from a bad one. With professional tools such as moisture meter, you may easily figure out the key factors that affect wood pellet mill quality. However, what if you don’t have these tools? I will show you 5 easy ways to judge whether a wood pellet is good or bad. With these steps, you don’t have to read hundreds of pages of wood pellet standard documents, you don’t have to use any special, professional equipment.
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Step 1: 1. Look
First impression matters, this is also true regarding wood pellets quality. You can judge quality of wood pellets by its appearance. Good wood pellets have something looks the same in common:
- Uniform length: As a matter of fact, for a single wood pellet, there is little difference between a 30mm wood pellet or a 35mm wood pellet. However, talking about bulk wood pellets or bagged wood pellets, the length difference matters a lot. Uniform length reflects consistent and stable pellet mill performance. According to ENplus standard, the optimum length should be from 30mm to 40mm. If the length is very different, it probably caused by wrong setting of cutting knife of pellet mill. Another important specification is the diameter. There are mostly 6mm and 8mm pellets in the current market. Since pellet mill dies are designed with 6mm and 8mm hole, you don’t need to worry about this as the diameter are always the same no matter how the quality is.
- Less fines: Chances are you may exam pellets in a bag or in a pile. Then you carefully take out all pellets from the bag, or take a look at the bottom of the bag, you will likely see fines. Even the best quality pellets have fines. It’s inevitable. These finds are actually very tiny pieces of woody material. They are produced by pellets transportation. According to the standards, wood pellets contain fines less than 1% is acceptable. Too much fines is caused by weak compression ratio of pellet mill dies.
Step 2: 2. Feel
A good wood pellets surface shall be smooth and shining and has no cracks when you touch and feel it. If the pellet is not smooth and have high find content, you should check the compression ratio for pellet mill die. If you see cracks all over the body, then it is because the raw material has less water or the material is not well conditioned.
Step 3: 3. Smell
This method seems too easy to be convinced, right? But it makes sense. A quality wood pellet should smell as fresh wood flavor. That’s the smell of its raw material – pure sawdust or other wood material. But, if the pellets smell is strange, one of the most possible reasons is that raw material is not pure, or binder is used in production. A binder is sometimes used as glue in wood pellets production to make raw material stickier. You can read this article for more binder information.
Step 4: 4. Sink
Here is the method. Prepare one cup with water, firstly, put one wood pellet into the cup. The bottom line is that this pellet will sink. It is a common sense that objects with density higher than water will sink. DO NOT buy any wood pellets that can float. But there is an exception: some feed pellets produced for feeding animals needs float, such as fish feed pellet. Secondly, wait for a while, good quality wood pellets will dissolve and expand in a very short time, on the contrary, poor quality will be slower and harder as the raw material is not pure and too much binder inside.
Step 5: 5. Burn
This is an ultimate method for testing wood pellets because combustion is the final destination of a wood pellet. You can light a wood pellet with match. Good quality wood pellets are burnt easily as it contains pure sawdust. When the pellets start burning, watch the color of the flame, if you see flame in light yellow or brown color, congratulations, they are good ones. However, if the flame’s color is dark or strange, then it must either contain binders or raw material that is not pure. After burning, check the ash left, the better quality wood pellet is, the less ash content it left.
Step 6: Bonus Tip:
If you want to make your own wood pellets, then you need a machine called pellet mill. But quality of pellet mills is also different. Before buying a pellet mill, talk with the salesman about their pellet quality guarantee. If they know what good pellets standards are, then their pellet mills can work well, then this pellet mill supplier can be trusted.