How It Works

Theory of Chlorination and Operation

Sodium hypochlorite, “NaOCl” (also known as “hypo”, “bleach”, or “liquid chlorine”), is a powerful oxidant that is used world-wide for the chlorination of water for disinfection

Sodium Hypochlorite

How on-site sodium hypochlorite is produced?

Salt is composed of sodium and chloride. When in solution and electricity DC is passed through special electrodes, the chlorides will disassociate to form chlorine. The process is basically as follows:

  • Electrolysis occurs in a cell when a DC current is passed through a saline water solution or brine.
  • At the anode: Oxidation of chloride ions produce chlorine (Cl2).
  • At the cathode: Reduction of water produce sodium hydroxide (NaOH) and hydrogen (H2).

Liberated chlorine reacts with the sodium hydroxide to generate sodium hypochlorite (NaOCl).

The overall reaction is as follows:

2NaCl (salt) + H2O (water) NaOCl (hypo) + NaCl (salt) + H2 (hydrogen)

Captura de pantalla 2023-03-21 a la(s) 15.41.45

Dosing of chlorine into the water

One liter of 0.6% (6000 ppm) sodium hypochlorite solution mixed into 6000 liters of water will produce a 1ppm concentration. Likewise, to produce a 2 ppm concentration, add 2 liters of 0.6% sodium hypochlorite solution to 6000 liters of water.

Gals. Liters. Liters. Gals. Grams of Cl₂ Liters. Gals. Grams of Cl₂ Liters. Gals. Grams of Cl₂
1000 3800 1.3 0.3 7.6 1.9 0.5 11.4 2.5 0.7 15.1
5000 19000 6.3 1.7 37.9 9.5 2.5 56.8 12.6 3.3 75.7
6000 23000 7.6 2.0 45.4 11.4 3.0 68.1 15.1 4.0 90.9
7000 26000 8.8 2.3 53.0 13.2 3.5 79.5 17.7 4.7 106.0
8000 30000 10.1 2.7 60.6 15.1 4.0 90.9 20.2 5.3 121.1
9000 34000 11.4 3.0 68.1 17.0 4.5 102.2 22.7 6.0 136.3
10000 38000 12.6 3.3 75.7 18.9 5.0 113.6 25.2 6.7 151.4

Advantages of Electrochlorination:

Raw material:

locally available (water + salt + electricity).


generated at the point of use and application.

On demand:

only when required.

No bulk storage:

because is generated on demand.

Safe for the operator:

low concentration.

Safe for environment:

chlorine desomposes back into common salt.

Generate Sustainable Projects

Frequently Asked Questions

The disinfectant produced will contain 7 grams of available equivalent chlorine per liter of solution. The concentration is 7000 parts per million or 7000 ml per lit

The electrodes are warranted for five years, but with proper care will last well beyond that time. The power supply is warranted for one year after installation, but will last as long as the electrodes.

Mineral deposits accumulate on the surface of the electrodes during normal operation. The rate of accumulation depends on the quality of the water used to produce the sodium hypochlorite. To remove the mineral deposits the electrode needs to be submerged in a weak acid solution or white vinegar.

That depends on the amount of organic contaminants in the water. Typically you will want to dose enough disinfectant to neutralize all the organic material in the water and leave a residual of <0.5PPM of chlorine. A dose of 2 PPM is commonly used.

The chlorine available for disinfection contained in gas chlorine, calcium hypochlorite and sodium hypochlorite is exactly the same and do the same work.

It is not even required operator’s literacy or skills to properly operate the units. It is extremely easy to use and maintain.