FAQ of Pellet

1. The bending of pellet or it has many cracks at one side
This phenomenon happens when the pellets leaves the ring die. During the production, the cutter’s position is far away form the surface of ring die and the knife edge is blunt, the pellets which squeezed from the ring die hole is broken with hit or tearing but not cutting. At this time, part of the pellets is bending to one side, and the other side has many cracks. When the cracked pellets enter into the cooling machine or transmitted, they are easy to break from the cracked points which lead to much powdery material.

2. Length of horizontal crack is beyond the whole pellet
Similar with the situation 1, the cracks emerges at the transaction of pellet, but the pellets are merely not bending. When the fluffy feed materials with high fiber contents make pellets, it maybe happens. This is because the feedstock has fibers which are longer than the diameter of holes when they are compressed into the ring die. When the pellets are squeezed out from the ring die, the expansive action of fibers makes the pellet crack at the transaction of pellets which make the feed pellets looks like fir skin.

3. The vertical crack of pellet
There are some fluffy and elasticity materials in the formula of feed, this kind of materials are easy to expand after absorbing water content when they pass through the conditioner. After the compression of ring die, the pellet spring open with the vertical crack under the forth of water or the material own elasticity.

4. The pellets has radial type cracks form one point
This type of outer surface of pellet means that the pellet contains the materials with big particle. It is difficult for the materials with big particle to steam. They are difficult to absorb water content and the heat value in the steam which are not easy to soften like other fine material. While for the cooling process, it leads to different shrink and produce radial type cracks which increase the pulverization rate due to the different soften degree.

5. Irregularity of pellet surface
This situation happens when the feedstock has uncrushed material or the crushed materials with big particles during the pelletizing process. The materials are not fully softened and the pellets are hard and big. When they pass through the ring die hole of pellet mill equipment, they can not combine well with other material which makes the pellet sags and crests. Another situation is that the material has steam bubble after streaming, and the steam bubble produces air bubble in the feed pellet during the compression. At the time of discharging form the ring die of pellets, the outer surface of pellets are irregular due to the broken bubble caused by the changed pressure. Any kinds of feed with fiber contents are easy to emerge this kind of situation.

6. Whiskers shape pellet
When the pellet are making, too much steam can be storage in the fiber content or the powdery materials if it has been added too much steam. Therefore, instant changed pressure makes the pellet blow out which bulge out the fiber content or materials at the surface when the pellet compressed out form the ring die. It formed the prickly whisker, especially for the high starch, high fiber content feed materials are produced. The more the steam is, the more serious the situation is.

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How to Make Wood Pellets with Sawdust
Wood pellet as a kind of new green energy has been widely applied in Europe, South American and other countries around the world. As people become more and more concerned about the carbon emission and air pollution, wood pellet are popular for room heating and for commercial use in power station.

How to make wood pellets
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Development prospect of biomass pellet mill
Prospect of application of biomass pellet mill
Development prospects of biomass pellet mill