Use of simultaneous absorbance-transmittance and excitation-emission matrix (A-TEEM) spectroscopy to monitor source water contamination for waterworks

Abstract

Conventional oil-in-water analyzers used by waterworks have hydrocarbon detection limits at mg/L levels and do not identify the type of oil compounds. The objectives of this study were to evaluate a more sensitive optical instrument and the analysis method to (1) determine the signature excitation and emission matrixs of each type of oil (such as diesel, heavy oil, gasoline and kerosene) or their indicator organic compounds and enter them into the instrument's software library and (2) test out the effectiveness of the instrument in detecting the above-mentioned oil in local waterworks’ source and treated water. The patented simultaneous absorbance-transmittance excitation-emission matrix (A-TEEM) instrument method was used to identify and quantify low levels of organic contaminants present in a much higher background of other dissolved organic matter components in raw and treated water. Multivariate regression and machine learning techniques were applied and shown to have potential for alerting plant operators to organic contamination events. HIGHLIGHTS An A-TEEM instrument method is an efficient qualification and quantification method for the detection of oil contaminants in water.; An A-TEEM method is effective in the detection of water soluble fractions of oil contaminants in ppb level in raw and treated water matrices.; An A-TEEM method provides early warning alert for proactive prevention and corrective actions in responding to contamination events.;

Keywords

• early warning system
• fluorescence detection
• machine learning
• oil detection
• optical sensor
• water contamination