Vacuum salt is manufactured by recrystallization of purified brine.
Today, we no longer use natural saline springs for this, but apply the process of pouring water into solid salt deposits. A hole is drilled into the deposit between several hundred to thousand metres deep. Fresh water is poured through it, dissolving the salt in a controlled process, and more water is pumped in to bring the saturated solution to the surface.
On the surface, the crude brine is carefully purified and freed of undesirable minerals. This is important in order to ensure the residue-fee solubility of salt products. The purified brine is boiled in crystallisers, and the resulting salt mass is then centrifuged, dried and processed into ready products. These are suitable, among others, for use as food-grade salt, in electrolysis plants or as regeneration salts for water-softening purposes.
Evaporated salt is - as well as rock salt - graded into the required size of grain through
sieving, or pressed into tablets, compact salt or lickstones. Additional substances such as iodine,
fluoride, nitrite or folic acid are added to it, according to requirements and intended use.
Preservatives make the salt easier to pour and ensure even application.
