What do you know about pellets?
Pellets are small compressed (or solidified) pieces,
in ball or cylinder form, made of different type of
materials. From the procedural/process engineering perspective, the production of pellets is
assigned to the "agglomeration" and is also called "pelleting". This requires not only a higher
"density" but also the avoidance of dust and/or improvement of the
dosing. However, here we want to talk about wood pellets:
Pellet - just natural pure wood!
The small "pellets" are made under hight pressure of natural/untreated, dried so-called "sawmill by-products", without adding chemical binding materials. Wood pellets have a diameter of 6 mm and a length of 3,15 – 40 mm. This equals a heating value of approx. 5 kWh / kg. In other words: 2 kg of pellets correspond to a heating value of 1 litre of heating oil.
Even dough pellets come seldom alone, we take a closer look at single pellets in our lab.
Pellets under the microscope !
Pellets packed in sacks, or as "loose product" are called "bulk goods", although they are mostly transported in silo trucks, from where they are blown out.
Pellet silo truck while filling a silo
The combustible "wood pellet" is "defined" in the international norm ISO 17225-2, which substitutes the German norm DIN 51731 or also called ÖNORM M 7135.
The demands of the ISO norm are put into practice in Germany by the "ENplus" and are partly even surpassed.
The certification programme from "ENplus" checks every single Station, from the production up to the delivery at the end customer, in order to allow a high and comprehensive transparency and achieve a high quality reliability.
Pellets are a "natural product"!
Wood pellets with „lower“ quality are mostly used as industrial pellets like "co-firing" pellets for power stations.