Brine is the residual liquid after salt brine is repeatedly concentrated and crystallized in salt production. In addition to saturated sodium chloride, its components are mostly magnesium chloride and magnesium sulfate. It is a complex mixture with no chemical name.

This kind of brine, because it contains a lot of magnesium salts, has the ability to solidify in protein. If you use a small amount, you can order tofu. If the intake is too large, it can be fatal. For example, in Yang Bailao, you drink brine and commit suicide.

Now brine is the raw material of salt chemical industry, which can extract a variety of inorganic salts.