Chlorination of Water

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Chlorination of Water


the treatment of water with chlorine and its compounds. The most widespread means of water disinfection, chlorination is based on the ability of free chlorine and its compounds to inhibit the enzyme systems of microorganisms that catalyze oxidation-reduction processes. Chlorine, chlorine dioxide, chloramines, and chlorinated lime are used to disinfect drinking water. The amount to be added is established by sample water chlorination: it is determined by the chlorine absorptivity of the water, that is, the amount needed to combine with the organic compounds that predominate in the water. An excess amount of chlorine (residual chlorine) is introduced in order to destroy microorganisms that find their way into the water after chlorination. The content of residual free chlorine 30 minutes after chlorination should be no less than 0.3 mg/liter. In some cases, water is chlorinated twice, before purification (preliminary chlorination) and after purification (final chlorination). Should substances exist in water that may give it an unpleasant odor or aftertaste after chlorination, the water is treated with ammonia or ammonium salts before chlorination.

Chlorination is used to disinfect drinking water under field conditions; the most reliable method in this case is superchlorination, which provides an excess of active chlorine no less than 10 mg/liter upon exposure of at least 30 minutes. Superchlorination is also used to disinfect water in centralized water-supply systems when there are epidemiological indications. Superchlorination is followed by dechlorination, that is, the removal of excess chlorine by physical or chemical methods.

Chlorination is also used to disinfect waste waters and the water in swimming pools, to bleach various materials, and to remove iron from industrial wastes.


Rukovodstvo po gigiene vodosnabzheniia. Edited by S. N. Cherkinskii. Moscow, 1975.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
About instances of naegleria, she said proper chlorination of water at its sources of distribution at the sites of end users was prerequisite.
All these deaths were preventable only if chlorination of water was carried out in Karachi and other parts of the province.
The focal group for Naegleria Prevention has been notified to remain functional till October 31 this year and shall formulate its prevention based strategy on daily basis with due attention to ensure chlorination of water supplied to the citizens in accordance to the WHO standards.
Al-Mushaki pointed out that the participants in the campaign They will take part in awareness lectures epidemic and first aid methods, while in mosques there are lectures, awareness seminars, pamphlets and posters for the epidemic, as well as chlorination of water reservoirs of mosques.
CLEAN WATER: Commissioner Malakand division Riaz Khan Mehsud on Thursday directed the KP Food Safety and Halal Food Authority for chlorination of water in schools and residential areas to ensure disease-free environment there.
She said that Naegleria can only be prevented through chlorination of water and other measures for leak proof supply of water.
Earlier, a meeting was held under chair of Sindh Minister for Health Dr Azra Pechuho on safe drinking water and chlorination of water in Karachi and Hyderabad.
He explained that chlorination of water is considered to be the only cure against the spread of the deadly Naegleria Fowlerdisease and other waterborne diseases.
PESHAWAR -- The Higher Education Department Khyber Pakhtunkhwa, has directed regarding cleaning and chlorination of water facilities in government run colleges and varsities across the province.
He said WASA Managing Director Syed Zahid Aziz had directed staff to carry out flushing and chlorination of water lines on an emergency basis and if complaint was received from any area under such scenario chlorine quantity should be increased there and cleaning process should be continued till the clearnance of water sample.
For his part, South Darfur Humanitarian Aid Commissioner Jamal Youssef said they equipped more than 23 cars to participate in the cleaning campaign, with national and foreign organizations, while the security services supported the chlorination of water sources by dozens of cars.