The kinetics of color destruction by oxidants

Abstract

The Long Beach Water Department (LBWD) treatment plant presently employs conventional methods to treat groundwater sources which exhibit a characteristic color caused by naturally occurring organic matter. The incorporation of ozone into the treatment process train was investigated to enhance color removal. The effective dose and contact time required to meet the secondary color standard was found to be a function of initial color content of the water. UV absorbance was found to be a good surrogate parameter for color. Correlations using raw and ozonated water data exhibited a coefficient of determination (r²) of 0.81 and 0.70, respectively. The determination of a reaction kinetic model to describe color disappearance with ozone contact time was inconclusive. The ozone contact system was found to be mass transfer limited at ozone doses greater than 5.0 mg/l.