Black lime can easily be bought in the market. The price of the product will depend on the region, the manufacturer and some features, for example, the bag of construction ineffective lime (about 40 kg) will cost you about 200-400 rubles. Formally negative lime is known as calcium oxide (CAO).
This is a caustic alkaline substance, which is carried out by heating limestone in special industrial furnaces (they are designed for this purpose). Apply the resulting substance for different purposes, and many companies produce and sell it with bags, sometimes with certain chemical impurities, so that the product is better consistent with a specific task of using.
People have learned to produce earnest lime for a very long time (about thousands of years ago), and chemists even believe that the formation of this substance can be one of the oldest chemical reactions known to a person. Now the negative lime is used in many industrial processes, some of which are characteristic of our century, but some have been developed hundreds of years ago.
In construction, the product is used with different purposes, for example, lime cement was previously produced from it, although now they are almost not done (it absorbs a lot of moisture, which leads to the fungus). But most building materials still do not do without this powder (plastering materials, bricks, paints, etc.P.)
With the help of negative lime, wastewater is neutralized, trees are whitened, plants are treated from pests.
In industry, unheated lime is most often used by those who produce food (it is part of the products as an emulsifier).
Production and quality of negative lime
Limestone is thrown into the furnace, which heats it to a very high temperature. High temperature makes carbon dioxide get out of stone, and the remaining passes after cooling is chopped into powder and packaged for sale.
Many things can be influenced by the quality of the negative lime, some of which are independent of the manufacturer. So, the plant can control such a factor as the temperature of the furnace (it also affects the quality of the substance), but cannot control natural impurities in stone. Since limestone is natural products, it is enough to isolate these impurities. Therefore, companies that take care of the quality of the goods sold are usually tested on a regular basis, which is the only key to high quality. The quality of the powder also depends on the workers at the factory, so they make sure that the stoves are heated and cooled by limestone with the corresponding speed.
With an open lime, you need to handle carefully. If it is incorrectly stored, then it will “absorb” carbon dioxide from the air, and will return to its original form. This is the reason why the negative lime is quickly used, especially after a mixture with water.
Lime is extremely caustic, so it can burn the skin.