Secondary Brine Purification
Mercury electrolysis or diaphragm electrolysis method were used for manufacturing caustic soda and chlorine soda in the past,however, recently it has been converted into ion exchange membrane method in Japan due to pollution control, saving the energy and keeping high quality.
If there contains much hardness in the brine, it is deposited in the membrane and causes the fall in electricity efficiency and the increase of the power consumption. This is the reason why the ion exchange membrane method requested high quality of brine.
Only Ca and Mg are noticed as the impurities in the past, however, Sr is also recognized as the impurity as pointed out by some membrane manufacturer and then requested to reduce to the same level as Ca, Mg. Our brine purification plant removes Ca , Mg and Sr to the desired level from the brine which contains small amount of alkaline-earth metal after primary purification process.
Example : 2 Tower Type of Secondary Brine Purification Plant
Example For Purification Process