China's sea salt production, the general use of solarization method, also known as the "beach sunshine method", is the use of coastal mudflats, damming salt fields, through the tide of water, attract seawater into the pool, through the sunshine evaporation into the brine, when the brine concentration of evaporation to reach the Boomerang 25 degrees, the precipitation of sodium chloride, that is, for the original salt. Sun-drying method of producing raw salt has the advantages of saving energy and lower cost, but affected by geography and climate, it is not possible to build salt fields on all coastal beaches and sun-drying salt in all seasons. Dry air, long sunshine, evaporation, salt production is high, and vice versa, production: low. In the northern salt fields of China, only from March to November is the season for sun-drying salt.

Sun-drying method of producing raw salt, the process is generally divided into four major processes: natatorium, halogenation, crystallization, salt collection.

1. Nachao

It is actually the raw material extraction process for the production of raw salt. Seawater is the raw material for salt production, in order to ensure the normal production, we must do everything possible to ensure the supply of raw materials. At present, there are two types of tidal wave, one is natural tidal wave, and the other is dynamic tidal wave. Natural tide is in the high tide to let the sea water along the tide ditch natural flow of people; dynamic tide generally use axial flow pumps will be introduced into the sea water, which is characterized by the natural conditions are not limited.

2. halogen

Halogen production is carried out in a wide area of the evaporation pond, according to the daily evaporation of appropriate control of the depth of the evaporation pond to go, so that the concentration of brine gradually increased, and finally concentrated into saturated halogen.

3. Crystallization

Sea water in the continuous evaporation and concentration process, the concentration of various salts continues to increase, when the concentration of salts to reach saturation, will be precipitated in the form of crystals, in the supersaturated solution, and constantly maintain the degree of supersaturation, the crystals will be able to continue to grow.

4. Salt collection

is the growth of salt, the use of artificial or mechanical salt collection pile.

(B) well mine salt production

well mine salt production is mainly divided into two parts of the extraction of brine and salt production. Different types of ore using different methods of extraction of brine. Extraction of natural brine methods are lifting and salvage method, gas lift method, oil extraction brine, deep well brine pumps, self-injection brine extraction methods. In the rock salt mining area, most of the water-soluble mining method is adopted by drilling, some use single well convection method, and some use double-well hydraulic fracturing method.

1. Convection method

This method is one of the more commonly used methods for mining rock salt deposits at home and abroad at present, with a higher degree of mechanization and lower cost. It makes use of the rock salt ore has dissolved in water characteristics of mining, the specific method is: hit a well to the salt layer, under two layers of casing, outer casing with oil liters of cement to fix the well, from one of the layer of pipe injection of water, dissolve the salt layer, by another pipe to the brine pumped up.

2. Fracking method

This method is to drill two drilling wells on the ground, put down the casing, seal the well pipe with the well wall, and press the high-pressure water from one of the wells to form a channel in the salt layer, dissolve the salt layer, form the saturated brine, and then press it out of the ground from the other well and deliver it to the production. Salt production is carried out in the plant, the brine purified from the brine storage tank is fed into the tank and heated by steam to evaporate the water. After evaporation, the brine becomes half-salt and half-water salt slurry, which is then dewatered by centrifuge and fed into boiling bed drying for finished salt; if the brine contains more manganese nitrate, it can be raised by freezing mother liquor or thermal method; Jiangxi Salt Mine introduces the salt-nitrate co-production process of Swiss Sulzer, which is a leading representative. If the brine contains more gypsum, gypsum is proposed to ensure the quality of salt.

(C) the production of lake salt

Lake salt is divided into primary salt and, regeneration salt, mainly using the extraction method or beach sunshine method. Extraction, some of the lake after a long period of evaporation, sodium chloride precipitation at the bottom of the lake, do not need to be processed can be taken directly. Such as the salt lake in the qaidam basin, after tens of millions of years of change; the formation of a dry lake, its salt on the surface. Various places are now producing with salt mining machine or salt mining ship, and its process flow is roughly as follows: stripping the coverings - salt mining - pipeline transportation (or automobile transportation) - washing, dehydration a Belt machine conveying a finished salt people pile. As for the beach sunshine method is similar to the sea salt production process.