A Review on Disinfection and Disinfection Byproducts
Surbhi Tak, Bhanu Prakash Vellanki, Satinder Ahuja
Abstract
To ensure the microbiological safety of treated water, disinfection is a crucial step for any drinking or wastewater treatment system. There are numerous ways of disinfecting treated water, chlorination being the most widely used technique in developed as well as developing nations. Other methods (i.e., UV, ozone, etc.) are also very prevalent and are much more expedient than the former. This review gives a comparative assessment of different types of disinfection systems. UV disinfection is the most effective in terms of germicidal efficiency, and it requires fewer resources to operate and maintain such a system. To achieve chemical along with microbiological safety of treated water, it is crucial to consider the other harmful chemical byproducts that are formed during treatment. In comparison to chlorine and ozone as disinfectants, UV disinfection produced fewer byproducts. Chlorine tends to react with the natural organic matter (NOM) present in the water and, in some cases, effluent organic matter too, giving rise to a variety of disinfection byproducts (DBPs). It then becomes crucial to incorporate various identifying and coping mechanisms to deal with the problem of DBPs. Gas chromatography (GC) coupled with mass spectrometry (MS) is the most common type of instrumentation used for analysis of DBPs in water samples. The removal of DBPs is mostly found to be concentrated on their precursors, which were targeted using advanced processes like adsorption, membrane filtration and advanced oxidation, or synergy of oxidation with biofiltration.