Wood pellets are a common biomass fuel with the advantages of green, renewable, and environmental protection. Therefore, more and more people pay attention to them. The process of making wood pellets mainly includes raw material processing, crushing, drying, pressing, cooling, and screening. Waiting for multiple steps, we will introduce the manufacturing process of wood pellets in detail below.
Wood pellet manufacturing process
Raw material handling
The selection of raw materials has an important impact on the pelleting effect and quality. Generally speaking, the raw materials of wood pellets mainly include sawdust, wood, waste wood and crop straw, etc. Different raw materials need to be treated differently. For example, wood chips need to be removed impurities, Screening, drying and other treatments, wood blocks need to be crushed and peeled, waste wood needs to be crushed and impurities removed, and crop straw needs to be crushed and dried.
Broken
After the raw material is processed, it needs to be crushed, and the raw material is crushed into granules to facilitate the subsequent drying and pressing. The crushing process needs to be carried out by using equipment such as a sawdust crusher.
Dry
The crushed raw materials need to be dried to control their moisture content below 10%. By reducing the moisture content, the quality and calorific value of the particles can be improved. Drying methods include natural drying, solar drying, mechanical drying, etc.
Suppress
The dried raw materials need to be pressed and made into wood pellets. The pressing process needs to be carried out by using equipment such as a wood pellet machine. The function of the wood pellet machine is to press the raw materials through the die holes to form cylindrical wood particles.
Cool down
The compressed wood pellets need to be cooled to reduce the loss and fragmentation of the pellets. The cooling method is usually to cool the wood pellets through a cooler. The function of the cooler is to cool the wood pellets through the cooling tube to reduce the particle size. temperature.
To sieve
After cooling treatment, screening is required to separate the wood particles that do not meet the requirements. The screening method is generally through a vibrating screen.
Package
The sieved wood pellets need to be packaged to facilitate storage and transportation. Usually, there are two types of packaging for wood pellets: bagged and bulk. Bagged wood pellets are packed into bags, and the weight of each bag is generally 15-25 kg. In bulk, wood pellets are directly loaded into vehicles or storage containers, and appropriate containers need to be selected for storage and transportation.
The manufacturing process of wood pellets includes multiple steps such as raw material processing, crushing, drying, pressing, cooling, screening and packaging. In each step, attention needs to be paid to controlling the moisture content of raw materials, selecting appropriate equipment, controlling pressing pressure and Screening accuracy and other factors are required to ensure the production of high-quality wood pellets. At the same time, it is necessary to pay attention to the hygiene and safety of the production environment to avoid contamination and damage to the pellets.