The Effect of Bromide on Trihalomethane Formation

Author

James C. Bird, University of Tennessee - Knoxville

Date of Award

8-1979

Degree Type

Thesis

Degree Name

Master of Science

Major

Environmental Engineering

Major Professor

Roger A. Minear

Committee Members

Dennis W. Weeter, Ekrem V. Kalmaz

Abstract

A study was conducted to examine the effect of bromide on the formation and distribution of trihalomethanes in drinking water. Chlorination experiments were made under controlled laboratory conditions of bromide level, chlorine dose, pH, ionic strength, temperature, and organic precursor concentration. Two types of raw waters were chlorinated: pure humic acid solutions and filtered Tennessee River water. Resulting trihalomethane formations were monitored over 96 hour reaction periods.

The results indicated that bromide can be an important factor in THM formation. An increase in TTHM yield and a shift toward more brominated THMs was observed for an increase in initial bromide level. A decrease in the effect of chlorine dose on TTHM yield and distribution was noticed with an increase in initial bromide level. For a given level of bromide, a decrease in humic acid level was found to be associated with an increase in the amount of bromine THMs relative to the amount of chlorine THMs. Ionic strength was found to have no influence on TTHM yield or distribution for the levels of bromide examined. The effect of pH on TTHM yield was observed to be enhanced at higher levels of bromide. The temperature dependence on THM formation was found to be strongly influenced by the bromide level. The temperature dependence of CHC1₃ formation was found to decrease with an increase in bromide. The temperature dependence of CHC1Br₂ formation was found to be greatest at a level of bromide corresponding to its predominance in the TTHM distribution. The temperature dependence of CHC1Br₂ formation was found to be greatest at a level of bromide corresponding to its predominance in the TTHM distribution. The temperature dependence of CHBr₃ formation was found to increase with an increase in bromide level. Similar bromide and temperature effects were observed with the chlorinations of Tennessee River water. In general, a first order computer simulation of THM formation did not give a good fit.

Recommended Citation

Bird, James C., "The Effect of Bromide on Trihalomethane Formation. " Master's Thesis, University of Tennessee, 1979.
https://trace.tennessee.edu/utk_gradthes/1714