1. What is calcium hypochlorite?

The main components of bleaching powder commonly used in aquaculture are calcium chloride and calcium hypochlorite. Among them: the active ingredient of bleaching powder for disinfection effect is calcium hypochlorite [Ca(ClO)2], and calcium chloride is a chemical substance that will obviously absorb moisture. It is precisely because of the presence of calcium chloride in bleaching powder that bleaching powder The available chlorine is easily affected and decreased.

Since calcium hypochlorite is the essence of bleaching powder, calcium hypochlorite is also called bleaching powder essence in the market. Compared with bleaching powder, it is pure calcium hypochlorite essence without moisture-absorbing substances such as calcium chloride. Chlorine is about 68%, which is significantly higher than the effective chlorine content of bleaching powder that has just been produced and has not been damp. The general disinfection dosage only needs 0.1~0.2ppm.

In aquaculture and other industries that require disinfection and oxidation, all disinfectants that dissolve in water and generate hypochlorite are generally referred to as chlorine-containing disinfectants. The bactericidal ability of chlorine-containing disinfectants is closely related to the amount of effective chlorine it contains. The higher the effective chlorine, the stronger the disinfection and oxidation ability.

2. Comparison of the advantages and disadvantages of bleaching powder and calcium hypochlorite

Advantages of bleaching powder:

It is cheap and has a clear effect on general pathogenic microorganisms.

Disadvantages of bleaching powder:

Because the calcium chloride contained in bleaching powder is highly absorbent, it is easy to decompose in the presence of light, water, heat, etc., and is not resistant to storage. Especially in humid areas, the effective chlorine of bleaching powder will decrease geometrically in about a month. Even lead to the loss of the proper disinfection effect.

The principle of bleaching powder deterioration:

Calcium chloride in bleaching powder absorbs moisture, causing calcium hypochlorite in bleaching powder to generate hypochlorous acid.

3. Hypochlorous acid will decompose into hydrogen chloride and oxygen under the condition of light, thus losing available chlorine.

Advantages of calcium hypochlorite:

Calcium hypochlorite contains very little hygroscopic calcium chloride, so calcium hypochlorite is relatively stable and resistant to storage and transportation (this is very important to ensure the disinfection effect). Compared with bleaching powder, the available chlorine of calcium hypochlorite is stable and high, and has a clear effect on general pathogenic microorganisms. The amount of use in disinfection is small, which reduces the amount of labor.

Disadvantages of Calcium Hypochlorite:

Because calcium hypochlorite contains a high amount of available chlorine, it is necessary to take protective measures during operation.