Two-wavelength nephelometry for the recognition of particulates using optical fibers

As it is able to provide two-wavelength and multiangular scattering measurements, the optical fiber nephelometer presented demonstrated an ability to measure simultaneously the concentration of a suspension and its type, whether F or C, thus removing the intrinsic ambiguity of conventional turbidimeters. The use of optical fiber technology made it possible not only to obtain a compact and versatile device for online monitoring, but also an instrument capable of performing very accurate scattering measurements as far as the angular resolution of these measurements is concerned. The effectiveness of PCA data processing was enhanced by this optimized accuracy, which enabled a discrimination between very similar type of particulates. For these reasons, the optical fiber nephelometer has the potential to discriminate also mixtures of suspensions, provided that an increased number of data is available, for example by means of multiwavelength measurements. Experimental tests are in progress in this direction.