1-7-1- Baked perlite and its characteristics
If a perlite rock has a temperature equal to 700 C to 1200 C, precisely near to 850 C due to temperature increase, resulted pressures from water evaporation in that and because vitrite is soft in this temperature and it has a paste manner so abrupt release of vapor and volatile gases are threatened in the material and it is easily provided and it has created very fine pores in perlite rock in perlite rock.
In other words, perlite grains are just like flourished grains and combined water is lost and they create some vitric bulbs that have considerable physical characteristics. During softness by creation of these fine pores, vitric body is with low specific weight into very light white material and much volume.
These minerals result in much decrease in conductibility of sound and perlite temperature.
Increase degree is a volume with type and chemical composition of first rock of perlite physical characteristics of perlite is as follows:
Fracture index: 1.5
Free moisture: 0.5
2-7-1 –Hydrophobic perlite
A perlite that one layer from hydrophobic or cellulose materials are stick to its surface without any damage to that and or we should decrease its physical quality and it is named in terms of hydrophobic perlite which is in type of baked perlite. Construction of these types of perlite is limited to a check and Slovakia. From types of baked perlite we can name.
A – Shell products
B- Graded products from 0.5 to 4 mm.
C – Some products with low volume weigh and maximum 0.25
Most important type of hydrophobic perlite , common in European countries , separating hydrocarbons from polluted waters : Its other usage is in agriculture and foods industry Baked perlite is neutral from hydrophobicity and it is not necessary for health it is as a result of drinking which are gained from treatment and it is health and consumable .