Caustic-Chlorine (Diaphragm Cell)

Abstract

Salt is dissolved in fresh and recycled water and sent to brine treatment for calcium and magnesium removal. The brine enters the electrolytic cells for electrolysis by low voltage direct current, produced by transforming and rectifying high voltage alternating current. The chlorine from the cell is chilled and then dried by contact with 98 percent sulphuric acid. Gaseous chlorine is compressed for delivery. Weak caustic soda/brine mixture leaving the cell contains 11 percent caustic soda. This is concentrated to 50 percent and then cooled to crystallise out the salt.