pelleted

Pelleted is an adjective used to describe material that has been formed into small, dense pieces called pellets. Pelleting is an agglomeration process that converts powders or granules into uniform units by forcing material through a mill and cutting to length. The method may involve heat, moisture, or binding agents, and the choice of equipment determines the finish and durability of the pellets.

The pelleting process can be hot or cold. Hot pelleting uses steam or heat to soften binders and improve cohesion, while cold pelleting relies on mechanical pressure and binders without added heat. Typical pellet mills use a rotating die and rollers (ring-die or flat-die designs). Properties such as moisture content, particle size, and binder type influence pellet integrity, density, and durability. Common measurements include pellet length, diameter, and pellet durability index.

Pelleted products appear in many sectors. The largest use is in animal feed, where pelleting improves flow, storage, and uniformity of nutrients. Wood, agricultural residues, and other biomass can be formed into pellets for fuel and heating. Fertilizers are sometimes pelletized to control nutrient release and ease handling. In plastics and polymers, resin powders may be pelletized to create uniform feedstock for further processing.

Advantages of pelleting include higher bulk and energy density, reduced dust and segregation, improved handling and packaging, and easier blending of multiple ingredients. Limitations include equipment cost, energy requirements, potential nutrient loss or damage from heat, and the need for careful moisture and binder management. Pellet quality is important and is monitored through standards and tests such as durability and uniformity.