How to identify good wood pellets?

Whether you plan to buy wood pellets or build a wood pellet factory, it is important to know which wood pellets are good and which are harmful. Due to the development of the industry, there are more than one standard for wood pellets in the market. The standardization of wood pellets is an established and unified specification for industry products. Since the publication of the Austrian Standard (ÖNORMM1735) in 1990, some EU member states have developed their own national particle standards, such as DINplus (Germany), NF (France), Pellet Gold (Italy), etc. As the world's largest pellet market, the European Commission has established an EU solid fuel standard (CEN TC335-EN 14961) based on the Austrian standard (ÖNORMM1735).

How to identify good wood pellets?

Wood pellet machine manufacturers tell you: how to quickly check the quality of wood pellets, just follow these steps:

1. Wood pellet diameter error: ≤1MM

The most common sawdust particles are 6mm and 8mm in diameter. Generally, the smaller the diameter, the better its particle properties. However, if the diameter is less than 5mm, it will increase energy consumption and reduce capacity. In addition, due to the shape of the particles, the volume of the product is compressed, saving storage space. In addition, it is easy to transport, so the transportation cost is low. In all existing standards, it is generally accepted that the diameter error does not exceed 1 mm.

2. Particle water content: ≤10%

According to all sawdust particle standards, the required moisture content is similar and does not exceed 10%. Technically, in this process, moisture is the binder and lubricant. If the moisture content is too low, the particles cannot be fully stretched, so the particles may deform and have a lower density than normal particles. However, if the moisture content is too high, the energy consumption will increase and the volume will increase. Generally, the surface of the particles will be rough. In severe cases, the raw materials may emerge from the pellet machine mold. All grain standards indicate that the optimal moisture for wood pellets is 8%, and that for cereal biomass grains is 12%. Particle moisture can be measured with a moisture meter.

3. Particle density: ≥600 KG / M3

The density of sawdust particles is one of the most important specifications, which can usually be divided into bulk density and particle density. Bulk density is a characteristic of powdered materials (such as granules) and the formula is the number of powdered materials divided by the required volume. Bulk density affects not only combustion performance, but also transportation and storage costs.

In addition, particle density also affects its bulk density and combustion performance. The higher the density, the longer the continuous burning time.

4. Granular mechanical durability: 96.5%

Mechanical durability is also an important parameter. During transportation and storage, particles with low mechanical durability are easily damaged and increase the powder content. Of all biomass particles, wood pellets maintain the highest mechanical durability, approximately 97.8%. Compared with all biomass particle standards, its mechanical durability is always no less than 95%.

5.Low chemical element content

For all end users, the most interesting issue is emissions, including NOx, Sox, HCl, PCCD (polychlorinated dibenzodioxins) and fly ash. The content of nitrogen and sulfur in the particles determines the content of NOx and Sox. In addition, corrosion problems are determined by the chlorine content. In order to have better combustion performance, all particle standards recommend the use of a lower chemical element content.