Discover. Connect. Capitalize.

Speakers Bureau View

43 Profile Views - 56 Presentation Views

Woo Hyoung Lee
Member

University of Central Florida

Connect

Presentation

Evaluation of nitrification in chloraminated drinking water distribution systems
Audience: Adults
Description: Biofilm formation in drinking water distribution systems has been associated with water quality degradation and may result in non-compliance with existing regulations. United States water utilities report biofilm survival and regrowth despite disinfectant presence, and systems that use chloramines to comply with disinfection by-product regulations will release ammonia which serves as a growth substrate for ammonia-oxidizing bacteria (AOB). If unchecked, these AOB can accelerate chloramine loss, leading to disinfectant depletion. Once this occurs, utilities have very few options available to correct the situation and often switch to free chlorine for a period of time to remove the growth substrate (ammonia) and inactivate biofilm. Currently, the only method to assess effectiveness of the switch to free chlorine is to measure free chlorine concentrations in the bulk fluid, but this may be unrepresentative of the free chlorine concentration in the biofilm. Biofilm is considered more resistant than suspended cultures, and thus it is important to understand the dynamics of biofilm activity and viability related to disinfectant biofilm penetration. Previous research has shown by direct measurement that monochloramine penetrates faster and farther into biofilm compared to free chlorine which exhibits limited biofilm penetration. The current research seeks to provide a better understanding of free chlorine application to nitrifying biofilm by monitoring free chlorine penetration over an extended period of time and assessing activity and viability through the entire biofilm depth to the substratum.

Keywords: Chloramine
Disinfection
Drinking water
Nitrification
Duration: 1 hour or less
Fee: Expenses Only

© 1999-2017, State of Florida