Is it feasible to make salt from seawater to purify as follows?

Seawater is first introduced into the salt pans, and then dried in the sun to evaporate the water, and after the water in the salt pans evaporates at night, only coarse salt remains.

Coarse salt contains insoluble impurities such as sediment and soluble impurities such as magnesium chloride, coarse salt is removed by precipitation filtration, then water is removed by evaporation, soluble impurities are removed by chemical reaction, and finally pH is adjusted with hydrochloric acid.

The method of extracting edible salt from seawater is as follows:

Raising and lowering the temperature will cause the salt to crystallize, and impurities will also come out together. Dried salt: Table salt can be extracted from seawater. The extraction method is to introduce seawater into the salt pan on the beach, use sunlight and wind to gradually evaporate the water, slowly concentrate, so that the salt is crystallized and precipitated, and the remaining salt brine contains potassium chloride, magnesium chloride, and a small amount of sodium chloride.

They can be separated by the difference in solubility of the three substances. Analysis of the solubility of the three substances shows that at room temperature (20), the solubility (g) of magnesium chloride is greater than that of potassium chloride and sodium chloride. Therefore, adding the right amount of water to the mixture at room temperature dissolves most of the magnesium chloride in the water, allowing the magnesium chloride to be separated and removed.

Then, according to the characteristics that the solubility of potassium chloride below 27 is less than that of sodium chloride, an appropriate amount of water is added to the remaining mixture for the second time, and sodium chloride can be dissolved in water, so as to obtain crude potassium chloride. Crude potassium chloride is further crystallized and recrystallized to obtain refined potassium chloride.

Where the hell does the salt in the sea come from?

Because water on Earth is always in constant motion and circulation, 125 million tons of water evaporate from the surface of the ocean every year. This amount of water then turns into rain and falls to every corner of the earth, and this water flows and washes over the rocks and soil, carrying the water-soluble salts in the rocks and soil to the rivers and finally into the sea.

In this way, the ocean receives a steady stream of salts from the land, and in the process of evaporation of the seawater, these salts cannot evaporate with the water vapor into the air, but can only remain in the sea. Hundreds of millions of years have passed, and the salt in the ocean has accumulated more and more, and the sea has become salty.

1. Fill the sea water with large tea.

bucket, let it settle.

2. Then boil a bucket of boiling water outside. Note: The water for boiling water here is fresh water, you don't need much, 1 3 is fine. Once boiling, place a towel on top (for straining).

3. Then, put in the seawater.

4. Then heat. When the water hits the potatoes and they are about to dry out, pour them into a bucket and filter them once.

5. Heating and boiling, evaporating water, using constant boiling. This method is somewhat dangerous and will scorch your salt if asynchronous attention. The advantage is that it is the fastest method.

6. The brine after evaporating most of the water is still a little dirty, and the purification is completed.

The method of extracting salt from seawater is mainly to use seawater to dry salt, and the material separation method it uses is the crystallization method.

The solubility of table salt is less affected by temperature changes, and sodium chloride can be obtained by the method of steaming hood Hu hair crystallization. The use of seawater to dry salt macrobars is the method of evaporation crystallization to obtain salt crystals.

1. Solar evaporation method (also known as salt field method): solar evaporation method is a very ancient salt production method, and it is also a common method that is still used today. This method involves building many ponds on the shore that resemble rice paddies to dry salt.

The process of salt production includes the steps of tide acceptance, brine making, crystallization, salt mining, storage and transportation. Nati is the accumulation of seawater with high salt content in the repaired salt pans. Brine production is to gradually increase the concentration of seawater, when the water evaporates into the salt pan, the brine at this time is the brine, commonly known as "bubble flooding" mother liquor.

This brine is transferred in time to the next pool, the crystallization pool. The brine continues to be steamed in the crystallization pool, and the salt will gradually be deposited at the bottom of the pool, forming crystals, and it can be collected to a certain extent. Salt production in salt pans is greatly affected by the environment, and factors such as the salinity of seawater, geographical location, rainfall, evaporation, etc., will directly affect the salt production.

This approach is also relatively large in terms of land and human resources and needs to be improved.

2. Frozen salt production is a technology used in high-latitude countries to produce sea salt, such as Russia, Sweden and other countries, which are mostly used to produce salt. The principle of this method is that when the sea water is cooled to the freezing point of the sea water, the sea freezes. The ice formed by the sea has very little salt in it, and is basically pure water.

Removing the water is equivalent to the evaporation of the water in the salt drying method, and the remaining concentrated brine can be used to make salt.

3. Electrodialysis is a new salt production method produced with the development of crude seawater desalination industry. It makes full use of a large amount of "mother liquor" with high salt content produced by seawater desalination as raw materials to produce salt from Wang Qin. Compared with the salt field method, the electrodialysis method saves a lot of land, and is not affected by the season, with less investment and manpower.

Japan is currently the only country in the world that has completely replaced the salt pan method by electrodialysis. The process flow of electrodialysis salt production is: seawater filtration, electrodialysis to concentrate saline water, salt water evaporation crystallization, drying and packaging of finished products.

The evaporated brine can be used to produce other products. It is believed that with the progress of science and technology, human beings will adopt newer and higher technologies to make salt, and the salt industry will continue to step up to a new level.