This International Standard determines the fuel quality classes and specifications of graded non-woody pellets. This International Standard covers only non-woody pellets produced from the following raw material (see ISO 17225-1, Table 1:
2 Herbaceous biomass
NOTE 1 Herbaceous biomass is from plants that have a non-woody stem and which die back at the end of the growing season. It includes grains and seeds crops from food production or processing industry and their by-products such as cereals.
3 Fruit biomass
4 Aquatic biomass
5 Biomass blends and mixtures
NOTE 2 Group 5 Blend and mixtures include blends and mixtures from the main origin-based solid biofuel groups woody, herbaceous biomass, fruit biomass and aquatic biomass.
Blends are intentionally mixed biofuels, whereas mixtures are unintentionally mixed biofuels. The origin of the blend and mixture has to be described using ISO 17225-1 Table 1.
If solid biofuel blend or mixture contains chemically treated material it shall be stated.
NOTE 3 Thermally treated pellets (e.g. torrefied pellets) are not included in the scope of the International Standard. Torrefaction is a mild pre-treatment of biomass at a temperature between 200-300 C.