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Brief introduction of sea salt, lake salt and well salt

Salt can be divided into sea salt, lake salt and well salt according to different raw materials.

1 ? sea salt

The sodium in the ocean comes from the rain on the earth's surface, and the water flow is doped with the original mineral composition of the earth's crust. After hundreds of millions of years of accumulation, rivers and volcanic eruptions rich in various minerals on land and seabed have increased the salinity of seawater and formed today's oceans.

In addition to water molecules, more than 80 elements such as Na+, Cl-, SO42-, Mg2+, Ca2+, K+, HCO3-(CO32-), H3BO3, Br-, Sr2+ and F- constitute the main chemical components of modern seawater. The pH value of seawater is around 8.2, and there is a very close proportional relationship between the main components.

The production of sea salt is mainly the beach drying method. Taking natural seawater as raw material, the original salt was obtained through soaking, bittern making, crystallization and scraping.

2 ? salt lake

The chemical composition of salt lake is the main salt deposition from the lake evolution to the salt-forming stage. In the process of salt lake evolution, the lake water at different stages has different compositions. There are about 40 chemical components in salt lake brine, among which Na+, Mg2+, K+, Ga2+, Cl-, SO42-, CO32- and HCO3- are the main components. However, the concentrations of some rare elements, such as B, Li, Br, Rb, Sr, Cs, U and Th, are several tens or even hundreds times higher than those of seawater.

Because of the existence of solid and liquid in salt lake, the primary salt of lake salt is developed by mining method; The salt is recovered by beach drying.

3 ? Jingyan salt

Well salt comes from underground salt mines and underground brine and is formed by sedimentation and deep diagenesis. After being buried deep underground, ancient sedimentary water exchanged with underground minerals, which made the contents of elements such as Na, Cl, Ga, Mg, Br, I and B in groundwater higher than those in seawater, and even contained harmful elements such as Ba and Pb. Because of long-term biodegradation and volcanic eruption, underground sediments contain harmful substances such as hydrogen sulfide and sulfur-containing protein. Therefore, underground salt mines and underground brine need to be purified before edible salt can be produced.

Brine salt making process mainly includes brine purification, brine evaporation, salt separation, drying and packaging.