MAGNESIUM, BROMINE, AND OTHER PRODUCTS FROM SEA WATER 39 



about the utilization of waste products in many industries of this country. Among 

 the by-products which have been prepared from the sea-salt bitterns, are mag- 

 nesium sulfate, magnesium chloride, magnesia, milk of magnesia, magnesium 

 carbonate, potassium chloride, bath salts, low-grade salt, magnesium oxychloride 

 cements, and artificial stone. Metallic magnesium has been prepared on a small 



(,Courtesy Food Machinery and Chemical Corp.) 



Fig. 4-1. The Newark, California, plant of the Westvaco Chemical Div., Food Ma- 

 chinery and Chemical Corp. Here bromine, gypsum and magnesia are produced from 

 the bittern (mother liquor) which remains after the crystallization of solar sea salt. 



scale during experimental work on the utilization of bittern, but its production 

 was not commercially successful for economic reasons. 



Since 1930 the bitterns from the solar salt operations of the Leslie Salt Com- 

 pany of California have been utilized chiefly for the manufacture of bromine, 

 magnesia, and gypsum. Although the process, as now used by the Westvaco 

 Chemical Co., is relatively simple chemically, it is a chemical engineering opera- 

 tion of the first magnitude. 



Raw bittern is pumped from the storage pond to a mixing trough where sul- 

 furic acid is added to lower the pH to about 4. The treated bittern is pumped 

 to a measuring weir on the top of the bromine plant. At this point an anti-foam- 

 ing agent and a httle water are added. The bittern then enters the top of a 

 stoneware tower and is distributed over the cross section of the tower. Chlorine 

 and steam are passed upward through the tower which set free bromine which 

 passes out the top. The bromine is recovered and purified by distilling. As the bit- 



