Residual Sulfite

Sulfite occurs naturally in numerous minerals, and these dissolved minerals contribute to the mineral content of drinking water.

What is Sulfite?

Sulfite can be found in most natural water sources and is one of the major dissolved components of rain.  High concentrations of Sulfite in the water we drink can have a laxative effect when combined with calcium and magnesium, the two most common constituents of hardness.  It can also cause water to have a bitter taste.

Sulfite is widely used for the dechlorination of wastewater in many treatment facilities. Dechlorination minimizes the effect of potentially toxic disinfection by-products by removing the free or total combined chlorine residual remaining after chlorination, which can prove toxic to fish in the receiving stream.

Sulfite monitoring

With residual chlorine discharge limits often very close to zero, monitoring residual values to comply with regulations has become very difficult and controlling residuals at values between zero and 10 or 20 parts-per-billion is often not achievable. To meet stringent discharge limits, the Sulfite or bisulfite used for dechlorination is added in slight excess, providing a small Sulfite residual to ensure complete dechlorination.

ATi’s Sulphite monitoring solutions provide accurate and reliable tools for maintaining a small Sulfite residual, while reducing excess chemical consumption due to overfeed. 

Contact us

Our team of experts are on hand to deal with any queries regarding our products or services.

Get in touch

A team of experts, ready to help

A global company with a caring culture. We have a team of experts on hand to help with any product or support query you may have. Contact us and experience ATi’s exemplary customer support.

Get in touch


Catch up on the latest from ATi

Case Study icon
Case Study
Continuous water quality monitoring of Ammonia

On-line monitoring of ammonia in water is of increasing importance due to the increased emphasis on nutrient reduction…

Case Study icon
Case Study
Disinfection monitoring & control for food & drink

Accurately controlling a dose of sterilant to clean pipework in the food and drink industry is vital to the taste, quality…

News icon
Badger Meter, ATi, s::can & Coftec announce partnership

Badger Meter and Coftec are pleased to announce the signature of a new partnership, bringing together leading…