SALT FROM SEA WATER 25 



consisting of a horizontal scraper mounted on a large caterpillar truck, has been 

 perfected. As the truck moves slowly along, the scraper takes up the salt and 

 throws it on a conveyor which empties it into the dumping cars. This mechanical 

 lifter can turn in any direction. 



When the salt is removed from the beds, it is often dark-colored due to admixed 

 iron sulfide, organic matter, etc.; occasionally it contains red, yellow, and brown 

 streaks. However, these discolorations may be removed by careful washing. 



The salt is next washed with brine, usually in large washing tanks. Revolving 

 screws in the tanks keep it in a state of constant agitation, turning it over with a 

 scouring action and drawing the salt up an incline to a point of discharge above 

 the water line which permits drainage by gravity. The loosened particles of foreign 

 materials float away with the overflowing brine. Lumps are broken up and the salt 

 is sprayed with fresh water as it passes up a conveyor and on to a huge stockpile. 



Some of the solar salt made in California is marketed in bulk without further 

 treatment. Much is dried in a kiln, then crushed, screened, and sacked. Large 

 quantities are refined by recrystallization, as will be described in the next chapter. 



REFERENCES 

 Ablan, L., Montilla, J. R., and Martin, B. M., "Salt-Making Industry of Northern Luzon," 



Phil. J. Sci., 72, 319-328 (1940). 

 Anon., "Production and Distribution of Salt in the United States by Primary Producers," 



Washington, U. S. Tariff Commission, 1935. 

 Anon., "Salt," San Francisco, Leslie Salt Co. 

 Anon., "History of Salt," Chicago, Morton Salt Co., 1949. 

 Anon., "Leslie Salt Expansion," Cliem. and Eng. News, 25, 1516 ( 1947 ) . 

 Anon., "Bay Area Salt Goes to Chlorine Plant," Chem. and Met. Eng., 53, No. 5, 198 



(1946). 

 Anon., "Salt," U. S. Bureau of Mines, Mineral Trade Notes, H, No. 2 (1940). 

 Badger, W. L., and Baker, E. M., "Inorganic Chemical Technology," 2nd ed., New York, 



McGraw-Hill Book Co., 1941. 

 Bartlett, H. W., "Salt Yielded by Sea Water Evaporation Harvested by Huge Tractor," 



Pit and Quarry, 20, No. 8, 22-26 (1930). 

 Bowles, O., "Non-metallic Minerals," Mining and Met., 25, 82-88 (1944). 

 Brighton, T. B., "Salt-Making on the Great Salt Lake," /. Chem. Education, 9, 407-415 



(1932). 

 Brighton, T. B., and Dice, C. M., "Increasing the Purity of Common Salt," Ind. Eng. 



Chem., 23, 336-339 (1931). 

 Buchen, J. C, "Evaporating Salt from World's Largest Mineral Deposit," Mining Met., 18, 



335-338 (1937). 

 Cole, L. H., "The Salt Industry of Canada," Ottawa, Canadian Dept. Mines, 1930. 

 Hamm, W. S., "Purer Salt for the Philippines," Philippine Institute of Science Spec. Bull. 



(1949). 

 Harris, F. E., "Marketing of Salt," U. S. Bureau of Mines, Information Circular, 7062 



(1939). 

 Harris, F. E., and Tucker, E. M., "Salt," U. S. Bureau of Mines, "Minerals Yearbook," 



1031-1045, 1946. 

 Harris, F. E., and Tucker, E. M., "Salt Output in 1948 Almost 16^ Million Tons," 



U. S. Bureau of Mines, Mineral Market Rept., 1739 (1949). 

 Hickok, K. E., "Non Metallic Minerals. VI. Salt," Mines Mag. (Colo. School of Mines), 



30, 642, 655, 660 (1940). 

 Hyler, J. E., "The Production of Salt," /. Chem. Education, 12, 203-207 (1935). 



