A method of quantitatively monitoring suspended oils in water combining the technologies of reversed-phase liquid chromatography and fiber optics is shown. A specially treated optical fiber collects and concentrates suspended oils on its surface so that optical transmission through the fiber is related to the contaminant concentration. The transmitted light from a treated optical fiber is detected by a photodiode and photocurrent is passed through an amplifier to give an electronic signal. The electronic signal is either recorded or indicated or generates a control signal whereby the light signal is translated into a value that corresponds to the concentration of oils suspended in water. To be sensed by the sensor cell, the fluid containing suspended oils is brought from a storage means to a reservoir and forced through the sensor cell by fluid pressure.
H. Stanley Silvus;Francis M. Newman;Robert K. Swanson