Types of pellets (definition)

Types of pellets — is a classification of pellets (fuel granules made from biomass) depending on the source material and their physical properties. The main difference between types of pellets is their ash content, that is, the amount of ash formed during combustion. Used in work pellet boiler.

Main types of pellets:

1. Wood pellets:
   • Description: Made from wood waste such as shavings, sawdust and wood dust. They can be made from a variety of wood species including softwood and hardwood.
   • Ash content: Usually have a low ash content, as wood contains less mineral substances. The ash content of such pellets is usually 0.2–0.7% of the fuel mass.
   • Advantages: High combustion energy, less ash formation and minimal maintenance requirements for boilers and heating systems.
2. Pellets from agricultural waste:
   • Description: Made from agricultural residues such as straw, corn stalks, husks and other plant residues. These are the so-called high-ash pellets.
   • Ash content: Usually have a higher ash content compared to wood pellets, since plant residues contain more mineral substances. The ash content of such pellets can reach 1.5–3% of the fuel mass.
   • Advantages: Extensive use of local resources and reduced fuel costs, but may require more frequent heating system maintenance due to higher ash content.
3. Peat pellets:
   • Description: Made from peat waste. They are often used in regions where peat is an available fuel source. Peat is the top pellet type with high heat output.
   • Ash content: Peat pellets have a high ash content, as peat contains a significant amount of mineral substances. The ash content of such pellets can exceed 5% of the fuel mass.
   • Advantages: Well suited for areas with large peat reserves, but may require regular cleaning of the heating system and boilers.
4. Pellets from biomass extracts and waste:
   • Description: Made from various biomass wastes such as plant extracts, animal manure and other organic waste.
   • Ash content: Ash content may vary depending on the feedstock, but typically these pellets have an ash content of 1–2% of the fuel mass.
   • Advantages: Use of waste, which helps reduce overall fuel costs, but there may be issues with consistent quality and increased ash content.

Conclusion:

Pellet types are taken into account when choosing a heating system, they affect the efficiency of the heating system and the frequency of its maintenance. Wood pellets are preferred for cleaner combustion and less ash, which reduces the need for frequent maintenance. Pellets made from agricultural waste and peat may be more affordable, but may require more frequent maintenance of the heating system due to increased ash content.