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Other Disinfectants

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Improve control of your disinfection process

The treatment processes for drinking water have changed during the last several years as increased concerns about disinfection byproducts (DBPs) and waterborne pathogens have become more prevalent. Many treatment processes now incorporate multiple oxidants or disinfectants to address these increased concerns. Other treatment objectives for these multiple oxidants include reducing taste and odor problems and facilitating the removal of dissolved metals.

Learn more about Ozone, chlorine dioxide and UV disinfection below.

Learn how chlorine dosing effects drinking water with an understanding of the chloramination curve.

 

 

Ozone (O 3)

 


What is Ozone?

Ozone (O 3), a powerful oxidant, is being increasingly used for water disinfection, primarily preoxidation. It was first used in the Netherlands in the late 1800s to disinfect drinking water and is now used worldwide in drinking water and wastewater facilities, swimming pools, spas, and in the bottled water and beverage industries. The major reaction products are oxygen, water, and carbon dioxide. For environmental safety, unreacted or residual ozone, while unstable, should be monitored.

Learn how chlorine dosing effects drinking water with an understanding of the chloramination curve.

Why Ozone?

Ozone quickly provides microbial sterilization and disinfection, organic compound destruction, and conversion of iron or manganese salts to insoluble oxides which can be precipitated or filtered from the water. However, one of the problems with ozone is that if overfed, it converts those oxides into soluble form. This is why accurate monitoring is critical.

Chloramination testing can protect your customers from harmful carcinogenic DBPs.

 

 

Chlorine Dioxide (ClO 2)

 


What is Chlorine Dioxide?

Chlorine dioxide is a deep yellow gas that is generated directly for onsite use as a bleaching agent in industrial processes, such as the manufacture of pulp and paper. It is used increasingly for special treatment objectives in municipal water treatment. Chlorine dioxide forms chlorite, a regulated byproduct, and chlorate.

Learn how chlorine dosing effects drinking water with an understanding of the chloramination curve.

Why Chlorine Dioxide?

Unlike chlorine, chlorine dioxide does not form trihalomethanes (THMs) in reaction with certain organic compounds. Chlorine dioxide forms significantly fewer halogenated DBPs than free chlorine generates and doesn’t react with ammonia to form less active chloramines.

Chloramination testing can protect your customers from harmful carcinogenic DBPs.

 

 

UV Disinfection

 


What is UV Disinfection?

UV rays can be an effective disinfectant in the water treatment process. It has been used in the commercial space for many years in the cosmetic, beverage, pharmaceutical, and electronics industries, particularly throughout Europe.

Learn how chlorine dosing effects drinking water with an understanding of the chloramination curve.

Why UV Disinfection?

Due to safety issues around chlorination and advancements in UV technology, UV is becoming increasingly accepted and utilized for water treatment in the U.S. UV light can disinfect water contaminated by bacteria and viruses and can fight protozoans such as Giardia lamblia cysts or Cryptosporidium oocysts.

Chloramination testing can protect your customers from harmful carcinogenic DBPs.

 

 

 

Why test with other disinfectants?

 

With any disinfectant, accurate and responsive monitoring and control are critical to avoid negatively affecting the treatment process and finished water quality

With analytical testing, you can:
• Maintain the desired ozone levels
• Determine UV lamp dosage settings
• Optimize chlorine dioxide levels for treatment

 

 

 

Explore Methods and Parameters

 

Chloramination testing can protect your customers from harmful carcinogenic DBPs.

 

 

Additional Resources

 

Learn about the benefits of monitoring monochloramine and free and total ammonia to control chloramination.

Learn about the Advantages of Ozone Treatment in Drinking Water

Ozone has been used for disinfection since 1906. Once considered inefficient and costly, the technology involved in ozone generation has improved making it a great solution for controlling biologic activity in water, tastes, odor and color issues.

LEARN MORE

Use the monochloramine and free ammonia Chemkeys™ to test for parameters associated with nitrification.

Chlorine Dioxide Requires Reliable Monitoring Protocols

Disinfecting drinking water with chlorine dioxide is becoming more common as utilities seek to reduce disinfection byproduct formation in finished water, but monitoring can be tricky. Learn why in this article

LEARN MORE

Learn how to maintain a precise ratio of chlorine and ammonia using online analyzers and integrated process control.

Chlorine Dioxide Chemistry Explained

Learn about the DPD and Chlorophenol Red Methods, the two primary methods for chlorine dioxide disinfection.

LEARN MORE

 

 

Which Options are Right for You?

 

Disinfection is a multifaceted process that involves a variety of factors, and every facility and operation is different. Whatever your needs, Hach is ready to help with information, technology, and support.

Explore the various parameters and methods associated with ozone, chlorine dioxide, and UV disinfectants below.

 

 

Disinfectant
Preoxidation 1 Post-disinfection 1
Positive Negative Positive Negative
Chlorine gas 2 Strong,
inexpensive		 High DBP, safety/
security issues		 Strong,
inexpensive		 Taste and odor (T&O),
DBP, safety issues
Monochloramine Less DBP Cost, process
control		 Longer living,
less DBP		 Nitrification,
T&O
Chlorine
Dioxide		 Kills giardia,
oocyst, less DBP		 Cost, safety Long living,
active		 Chlorite/
chlorate, cost
Ozone Strong, less DBP Bromate, little
residual, cost		 NA No residual
Hydrogen
Peroxide/PAA 3		 Strong, easy to
handle		 Bromate, no
residual, cost		 NA No residual
Permanganate Strong, easy to
handle		 MnO x
(staining)		 NA MnO x
(staining)
UV Strong, no DBP Cost, no
residual		 NA No residual

 

1 - Disinfectant activity comparison is based on CT values

2 - Hypochlorite is frequently used as an alternative in order to reduce risk of gaseous chlorine leaks and simplify the application

3 - Hydrogen peroxide is often used in mixture with peroxyacetic acid (PAA) to increase stability of the oxidizer

 

Explore the different types of parameters used in ozone, chlorine dioxide, and UV disinfection monitoring.

 



Why test for Ozone?

 

Test for ozone levels being delivered by the ozone generator. Maintain ozone levels to optimize the treatment process to reduce taste and odor problems, reduce disinfection byproduct formation, provide pathogen inactivation, and to facilitate removal of iron and manganese. Determine ozone concentrations to calculate CT credits.


Why test for Chlorine Dioxide?

 

Test for chlorine dioxide levels being delivered by the chlorine dioxide generator. Maintain chlorine dioxide levels to optimize the treatment process to reduce taste and odor problems, reduce disinfection byproduct formation, provide pathogen inactivation, and to facilitate removal of iron and manganese. Determine chlorine dioxide concentration to calculate CT credits for Giardia and virus inactivation.


What are Disinfection Byproducts (DBPs)?

 

Disinfection byproducts are formed when disinfectants, like chlorine, react with bromide and/or natural organic matter present in the source water. The EPA's established Stage I Disinfection Byproduct Rule regulates:

Total Trihalomethanes (TTHM): the sum concentration of four chemicals: chloroform, bromoform, bromodichloromethane, and dibromochloromethane. The EPA regulates TTHMs at an annual average concentration of 80 parts per billion

Haloacetic Acids (HAA5): the sum concentration of five chemicals: monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid. The EPA regulates HAA5s at an annual average of 60 parts per billion.

Bromate: a chemical byproduct formed when ozone reacts with naturally occurring bromide. The EPA regulates bromate at an annual average of 10 parts per billion.

Chlorite: a byproduct formed when chlorine dioxide is used to disinfect water. The EPA regulates chlorite at a monthly average level of 1 part per million.


What is UV-254?

 

UV-254 or SAC 254 is a measure of the organic substances absorbing UV light at the 254 nm wavelength. This measurement has shown to be a good indicator of the amount of organic material present that is likely to react with chlorine to form disinfection byproducts (DBPs). The method uses no reagents and requires an instrument capable of measuring light absorbance at 254 nm. The method is best used with surface waters like large reservoirs or lakes that have a relatively stable organic level. A change in the UV-254 absorbance value can indicate changes in water quality that may impact the disinfection process. Storm events, algal blooms, or reservoir turnover would be examples of events that could impact the UV-254 value and the subsequent treatment process. The UV-254 measurement is made by following sample filtration through a 0.45 micron filter. The UV-254 value is also used in the calculation of SUVA (specific UV absorbance) which is used to determine compliance for reducing DBP precursor material under the Disinfectants and Disinfection Byproduct Rules.


Why test for Permanganate?

 

The main goal of water treatment with sodium permanganate or potassium permanganate is to provide adequate preoxidation to remove organics and/or dissolved metals, such as manganese (Mn) and iron (Fe), from the water. Natural organic matter (NOM) removal is usually the primary goal for surface water treatment to minimize formation of disinfection byproducts (DBPs). Removal of metals by oxidation is usually the primary goal for ground water treatment; however, the general practice is to sequentially remove metals by precipitation and filtration.

Operational challenges usually come to determining and maintaining the correct feed of permanganate. The balancing act is between underfeeding permanganate and therefore not achieving the goal of NOM and/or metals removal and overfeeding that may lead to an unwanted pink color in finished water. In addition, over-oxidizing of Mn leads to its dissolution and therefore defeats the purpose of the treatment (inefficient filtration). To maintain such a delicate balance, the analysis of treated water must be constantly conducted in process and therefore online instrumentation is preferred for such applications. Instrumentation should provide accurate results and be robust.

 

 

Find the right testing solution

 

Select the attributes below to find the right disinfectant product for you.

 

Compare our different products used for various applications by exploring the resources and options below.