How Are Fuel Pellets Made with an electric wood pellet maker?

Jan 09, 2026

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The core objectives of raw material processing are "uniformity, dryness, and freedom from impurities." Only by meeting these three requirements can a small biomass pellet making machine efficiently produce high-quality pellet fuel. First, there's the issue of raw material type and impurity removal. Different raw materials require different processing approaches: wood chips and sawdust have fewer impurities and only need to be screened and magnetically separated to remove metallic impurities; agricultural raw materials such as straw and peanut shells have high fiber content and need to be crushed and then pulverized to 2-3mm to prevent fiber entanglement in the equipment; mixed raw materials (such as wood chips + straw) need to be mixed in a specific ratio to ensure sufficient lignin content and improve binding effect. Regardless of the raw material, hard impurities must be thoroughly removed. A three-stage impurity removal system of "manual sorting + vibrating screen + magnetic separator" can be built to reduce the risk of equipment wear.

Second, particle size control is crucial, as it affects pressing efficiency. Different types of electric wood pellet mills have slightly different particle size requirements: small flat die wood pellet making machines are suitable for 2-5mm particle sizes, while ring die wood pellet making machines, due to their higher pressing efficiency, require particle sizes controlled at 2-3mm. Particle size control is achieved through a combination of a crusher and a grading screen. The screen aperture of the crusher can be adjusted as needed. The crushed raw material is then screened by the grading screen, and particles exceeding the size limit are returned to the crusher for secondary crushing. It is important to note that excessively fine particles increase the specific surface area of the raw material, leading to faster moisture absorption and increased energy consumption; excessively coarse particles prevent sufficient compression within the die holes, resulting in low particle density and looseness.

Moisture content adjustment is crucial for pellet formation, with an optimal range of 12%-15%. Different raw materials have different initial moisture contents, requiring different treatment methods: fresh raw materials (such as freshly harvested straw) can have a moisture content exceeding 40%, requiring continuous drying in a dryer at a temperature controlled between 80-100℃ to prevent carbonization; dried raw materials (such as long-stored sawdust) may have a moisture content below 10%, requiring even water spraying with a spray bottle while stirring to ensure uniform moisture distribution. The adjusted moisture content needs to be verified using a simple moisture meter or by visually judging it using the "clumps together when squeezed, crumbles easily when released" method, avoiding inaccuracies due to experience-based judgment.

Practical techniques for raw material handling: Conduct small-scale trials before mass production, adjusting the pulverizing screen aperture and drying parameters according to the raw material characteristics; process different batches of raw materials separately to avoid uneven moisture content and particle size after mixing; complete processing of the treated raw materials within 24 hours to prevent secondary moisture absorption. Proper raw material handling can increase the forming rate of the biofuel sawdust pellet machine to over 95% and extend the equipment's lifespan.