Removal of Major Impurties (Ca-Mg) of Brine with Chemical Treatment Process in the Salt Sector

Yıl 2018, Cilt: 2 Sayı: 2, 57 - 66, 31.12.2018

İsmail Bayram

Öz

The operation of salt minerals dates back hundreds of
years. Salt is produced from salt rich sources through salts today. The salt
(brine) obtained from existing salt sources is not in the desired purity. For
this purpose, purification of the brine should be carried out to remove
unwanted impurities. Brine (raw salt) also contains impurities that are soluble
and insoluble except NaCl. 94-96% of the brine obtained from the salt lake
contains NaCl. The remaining 4-6% are MgCl2, MgSO4, CaCl2 and other trace
amounts. All of these substances are called solubility and insoluble
impurities. These impurities are magnesium, calcium and sulfate .Calcium
accumulation causes crust formation in the circulation line, especially heat
exchangers. For this reason, heat transfer and circulation effiency decrease.
The impurities from the dissolved raw salt (Ca+2, Mg +2 etc.) should be removed
by the purification process. Settling tests were carried out in brine
purification system. As the experimental results obtained, the magnesium and
calcium from the major impurities in the brine were separately and coherently
removed. NaOH was used to precipitate the magnesium and the dynamic run-out was
determined to be optimum pH = 11. Na2CO3 was used to precipitate the calcium from
the other major impurities in the brine. As a result of dynamic experiments,
optimum precipitation pH was set at 9,5.

Anahtar Kelimeler

raw salt (brine), chemical treatment, pH adjustment

Kaynakça

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