Significance and detection of residual chlorine in water

- Jul 23, 2020-

However, in actual situations, the residual chlorine in tap water will disappear or become too high due to various conditions, causing water trouble. Because the pipe network is too long or the pollution is serious, the residual chlorine in the tap water will disappear too quickly, and it will not have the effect of antibacterial. At this time, it needs to be added artificially, and often in the process of supplementing because of the lack of necessary detection tools, Adding based on personnel experience will cause excessive residual chlorine. The direct problem of excessive residual chlorine is that the chlorine smell of the water is very large. In addition, it may also be caused by the chemical reaction of some organic substances in the water with residual chlorine to produce toxic and harmful chemicals. In industrial water treatment, excessive residual chlorine will accelerate the damage of water treatment equipment and increase production costs.


Whether in domestic life or industrial applications, as long as tap water is drawn, residual chlorine detection is necessary. Since residual chlorine is a basic tap water indicator, its detection method is relatively complete. A complete detection method is provided in GB5750-2006. At the same time, since residual chlorine detection is a basic tap water quality indicator, it has very important significance. It also provides a variety of testing tools, including instruments, kits, test strips, etc., and users can choose different products according to actual needs and measurement ranges.


Multi-parameter Meter

Free residual chlorine: also known as Cl2, HOCl, OCl-system in free chlorine aqueous solution as free residual chlorine, which is a kind of residual chlorine component with good disinfection effect in water and strong oxidation.


Compound residual chlorine: When there is ammonium (amine, ammonia) in the water, chlorine will react with ammonium to produce chloramine (monochloramine, dichloramine, trichloramine). The bactericidal effect of chloramine is far weaker than hypochlorous acid, and it has a peculiar smell.


Total residual chlorine: the general term for free residual chlorine and compound residual chlorine


Usually we call "residual chlorine" means free residual chlorine, and "total chlorine" means total residual chlorine


Residual chlorine detector: Generally, electrochemical or spectrophotometric method is used for rapid residual chlorine detection. Its accuracy is high, and it is basically similar to traditional laboratory analysis methods, but it is simpler and easier to use.

residual chlorine detector

Residual Chlorine Test Box: A product derived from the standard method. Colorimetric method is used to determine the residual chlorine in the water through the color reaction of residual chlorine in water and special chemical agents. This type of product can detect the lower limit Generally it can reach 0.05mg/L, which can meet the needs of general household and industrial users

residual chlorine test kit  

Residual chlorine test strip: Compared with the residual chlorine test box, its detection range will be larger, but the accuracy will be worse than that of the residual chlorine test box. The usage is similar to PH test paper.

Residual Chlorine Test Strips 

If users have higher requirements, you can choose a residual chlorine detector. As a consumer-level user or general industrial site user, you can also choose a low-cost residual chlorine detection box.