Perlite in the natural state is a volcanic thick rock. With respect to chemistry, it is an aluminium silicate with other aggregated oxides (sodium, potassium, etc.). Originally, the ore is characterized by the presence of some H2O particles (water). The ore is dig out from the quarries, grounded and taken to a precise level of thinness. It is then pre-dried and expanded in expansion kilns. It is the presence of water that, thanks to the thermal shock (process with temperatures higher than 800°C), makes particles expand their volume twenty as much their initial volume. Perlite so expanded is very light and particles are empty spheres floating if put into water. The process of expansion gives it a high capacity of thermal insulation. These are the reasons why expanded perlite is used for cryogenic insulation, for construction and for hydroponic cultivations. In order to use expanded perlite as a filter aid, it is necessary to cool, grind, classify and pack it right after its egress from the kiln. The finished product can be packed in paper bags later pressed and palletized or in big bags. The product can also be stored in tanks (bulk movement).
PALUMBO TRADING markets the whole range of perlite-based filter aids and fillers produced by Dicalite Europe nv.