What Are the Raw Material Preparation Steps for Wood Chip Pellet Machines?
Moisture content control is a crucial consideration in the raw material processing of electric wood pellet mills and is key to the success of homemade fuel. The optimal moisture content for wood chips should be controlled between 12% and 15%. If the moisture content is too high (above 18%), the raw material will stick together in the pressing chamber, making it difficult to form properly. Even if formed, it will easily crumble and crack, and it will increase the frictional resistance between the pressure rollers and the mold, accelerating component wear. If the moisture content is too low (below 10%), the raw material lacks viscosity, requiring greater pressure during pressing, which not only increases energy consumption but also results in rough and brittle fuel pellets. When processing raw materials with high moisture content, a hot air dryer should be used, with the drying temperature controlled between 80-100℃ to avoid high temperatures damaging the lignin in the raw material (affecting viscosity). When processing raw materials with low moisture content, a suitable amount of water can be sprayed before feeding to adjust the moisture content. The water spraying should be even to avoid localized excessive moisture content.
Strict control of raw material particle size is an important prerequisite for ensuring uniform fuel forming. The particle size of the pulverized wood chips should be controlled between 2-5mm. Uniform particle size ensures even pressure distribution during pressing, consistent fuel particle density, and higher combustion efficiency. Excessively large particles increase the crushing load, leading to accelerated wear on crushing components and potential feed blockage. Large particle size variations cause pressure fluctuations in the pressing chamber, affecting molding stability. It is recommended to equip the machine with a grading screen to screen the pulverized material, ensuring only materials meeting the particle size requirements enter the pressing stage. For hard wood chips (such as hardwood chips), secondary crushing is necessary to prevent excessive particle size from affecting the molding effect.
Impurity removal is a crucial step that cannot be ignored and directly affects equipment safety. Wood chips often contain hard impurities such as metal blocks, stones, and sand. These impurities can directly impact the pressure rollers and molds, causing mold cracking, roller deformation, and in severe cases, damage to the equipment's transmission system. Therefore, before entering the Commercial Pellet making machine, the raw material must undergo multiple screening and purification processes: first, a vibrating screen removes large particles such as stones and sand, and then a magnetic separator adsorbs metal impurities. It is recommended to add impurity removal devices to the raw material storage and transportation stages, forming a triple impurity removal process of "initial screening before storage - secondary screening after crushing - fine screening before feeding".
In addition, attention should be paid to the matching of raw material types. Different types of wood chips have different characteristics, and the pressing parameters need to be adjusted accordingly to avoid mixing raw materials with excessively different processing characteristics. For example, softwood chips (such as pine and fir) have high lignin content and good adhesion, making them easy to shape; hardwood chips (such as oak and birch) have high hardness and poor adhesion, requiring an appropriate increase in pressing pressure. If softwood and hardwood chips are mixed, the mixing ratio needs to be controlled (it is recommended that the softwood content be no less than 60%), and the equipment speed and pressure should be adjusted to ensure stable shaping.
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FAQ
1.What is the price of equipment for a flat die wood pellet mill?
It costs approximately US$1,500.00 - 25,000.00
2. If equipments have some quality problem, how would you deal with?
We will responsible for all the quality problems. Change all the parts for free.
