Optospectral whiteness sensor and its use for monitoring the process of chlorine bleaching of cellulose
N. P. Belov, O. K. Pokoptseva, A. S. Sherstobitova, and A. D. Yas'kov
This paper discusses the main regularities of the influence of chlorine-containing bleaching agents on the diffuse reflection spectra of cellulose pulp. General rules are given for the use of optical technologies to monitor the consumption of such reagents in cellulose-bleaching processes. A description is given of the structural features and the most important technical-operational characteristics of an optospectral whiteness sensor intended to regulate the consumption of chlorine-containing bleaches and the production process flow. Wavelengths 457, 600, and 1000nm are used to measure the reflectance. Based on an analysis of the results of production tests, recommendations are given for optimizing the use of such a sensor to make it possible to eliminate the influence of concentration changes of the cellulose pulp and the reduction during operation of the transparency of the sensor's input window, caused by its being “overgrown” in the process flow.
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