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          Marine chemical industry and salt field
          ( chinadaily.com.cn)
          Updated: 2009-12-29

          The history of extracting salt from sea water in Hebei can trace back to the Ming Dynasty. In the Qing Dynasty, the average annual output of sea salt in Hebei reached 300,000 ton. The extracted sea salt can be used not only as the flavor but also in marine chemical production. Hebei’s salt industry has made great progress in terms of its variety, quantity and quality.

          1) Salt chemical engineering

          The salt field in Hebei Province contains rich bitterns.

          Early in the Ming Dynasty, bitterns were made into brine block as tributes for the Royal Family.

          The production of halide and mirabilites began to take shape in the Qing Dynasty.

          Ever since 1958, indigenous methods have been employed in the production of halide, thenardite, sulfate of potash-magnesia, Hydrochloric Acid, magnesium chloride, Sodium- -magnesian fertilizer, crude Nitrate, cyanide, sodium hudroxide , and sodium.

          Mechanization began to change the production of sea salt in 1970.

          In 1990s, four other series products of potassium, bromine, magnesium, and Nitrate began to sell to other provinces.

          2) Salt-extraction industry

          Salt extraction is one of Hebei's traditional industries and the province enjoy natural in the industry.

          A. Flat terrain and the muddy coast are suitable for brine evaporating

          B. The climate including high evaporation capacity, small amount of precipitation, and short rainfall season is suitable for brine evaporating.


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