Method of quantifying performance chemicals in pulp and paper

摘要

A method is provided for quantifying the amounts of performance chemicals selected from the group consisting of wet strength agents, starches and retention agents, hydrophobic agents and debonding agents, reacted or retained with the cellulose fibers in fluff pulp or paper. The method comprises (I) developing a calibration model by (I.a) registering absorption, reflectance or emission spectral raw data of reference samples of paper or pulp containing known amounts of the performance chemicals to develop a learning set; (I.b) processing the spectral raw data from the registered spectra to reduce noise and adjust for drift and diffuse light scatter; (I.c) performing a data analysis on the learning set in which the processed spectral data of the reference samples are transferred into latent variables based on principal component analysis, and applying chemometric techniques on the latent variables in order to find the mathematical expression of the calibration model; and (II) registering absorption, reflectance or emission spectral raw data of a sample of fluff paper or pulp containing unknown amounts of chemicals, processing the spectral raw data as according to (I.b); transferring the processed spectral data into latent variables as according to (I.c), and applying the developed calibration model on the latent variables in order to determine the unknown amounts of the reacted or retained performance chemicals.