Difference between residual chlorine and total residual chlorine

In the field of chemical production, water treatment and environmental protection, residual chlorine and total residual chlorine is a frequently mentioned term. These two concepts are sometimes easily confused, leading to misunderstandings. In order to help you better understand their differences and importance, this article will be from the definition, role, monitoring, calculation methods and other aspects of a detailed analysis.

Definition and difference between 1. residual chlorine and total residual chlorine

residual chlorine (Chlorine Residue, abbreviated as ClR) and total residual chlorine (Total Residue, abbreviated as TR) refer to the residues of chemicals that have not been completely removed from the water. There are significant differences in their definitions and calculation methods.

1. Residual chlorine (ClR): Residual chlorine refers to the total content of hypochlorous acid (HOCl) and its decomposition products (such as Cl, ClO, etc.) that have not been removed after treatment. Residual chlorine is usually used as an indicator of available chlorine in the water treatment process to measure the residual amount of hypochlorous acid.

2. Total Residual Chlorine (TR): Total Residual Chlorine is the sum of all chlorides in the water that have not been removed, including hypochlorous acid (HOCl), chlorate (ClOTL), chloride (ClTL) and their decomposition products. Total residual chlorine is one of the components of chemical oxygen demand (COD).

In simple terms, residual chlorine is the total amount of hypochlorous acid and its decomposition products, while total residual chlorine includes all forms of chloride. Therefore, the calculation range of the total residual is wider than that of the residual chlorine.

Analysis of the interaction between 2. residual chlorine and total residual chlorine

in practical applications, residual chlorine and total residual chlorine play different roles, as follows:

1. the role of residual chlorine:

• bactericidal effect the main function of residual chlorine is to kill bacteria, viruses and other microorganisms in the water through the strong oxidation of hypochlorous acid.
• bleaching effect: Hypochlorous acid can also be used as a bleaching agent in some cases and has the properties of bleach.
• Water treatment index: Residual chlorine is an important indicator to judge whether water reaches a certain quality standard, and is usually used for the treatment of industrial wastewater and domestic sewage.

1. Effect of total residual chlorine:

• environmental Impact Assessment total residual chlorine is an important indicator to measure the degree of chlorine pollution in water bodies, and excessive total residual chlorine may cause harm to the environment and human health.
• water quality monitoring total residual chlorine is an important indicator in water quality monitoring, which can reflect the content of chemical oxygen demand in water.

Monitoring and Calculation of 3. Residual Chlorine and Total Residual Chlorine

1. monitoring methods:

• residual chlorine (ClR): It is usually monitored by electrode methods (such as electrode sensors) or chemical methods (such as potassium iodide test paper).
• Total residual chlorine (TR): Because the total residual chlorine involves a variety of chlorides, the monitoring is relatively complex, and it is usually necessary to combine chemical analysis and electrode methods for comprehensive judgment.

1. calculation method:

• residual chlorine (ClR): The calculation formula is ClR = HOCl ClO₂ ClO₂ ClO₂ (according to specific standards).
• Total residual chlorine (TR): The calculation formula is more complex, usually need to consider a variety of chloride forms, including Cl, ClO, ClO₂, and their decomposition products.

4. Summary

residual chlorine and total residual chlorine are two closely related but easily confused concepts in water treatment and chemical production. Residual chlorine is the total content of hypochlorous acid and its decomposition products, which is mainly used to measure the bactericidal effect, while the total residual chlorine is the sum of all chlorides, which is used to evaluate the pollution degree and water quality of water bodies. Understanding their differences and functions will help to better water treatment and environmental protection.

Through the analysis of this article, we hope that readers can understand the difference between residual chlorine and total residual chlorine more clearly, so as to make accurate applications and decisions in practical work.