A process for preparing alternative fuels so that it is acceptable for use in cement plants and other manufacturing processes is detailed. The system calculates and analyzes first and second discrete derivatives to detect and determine the incidence of change in the voice waveform that would not have been made by human articulation because natural voice signals change at a limited rate. The ratio is determined by comparing a signal generated by one sensor through which a taggant particle containing component is flowing with a signal generated by another sensor through which the mixture is flowing delayed by the time required for the component to flow from the one sensor to the another sensor.