Abstract:

Based on the Kubelka-Munk equation and the spectrum features of the residuallignin in pulp , the theoreticalmodel describing the pulp diffuse reflection is established. According to the intemal relationship between theresiduallignin in pulp and the pulp Kappa number , the model for the on-line measurement of pulp Kappa numberis presented. Then , according to the absorbing spectrum of the residuallignin in pulp , F390 , FS60 and FS40 are usedas independent variables to build a simplified measuring model named "tri-wavelength". The simplified model issimple in structure and clear in physical description , and it can reveal the linear relationship between the Kappanumber and the independent variables. However , the proposed model omits the nonlinear relationship between theKappa number and the reflected spectrum due to the simplification and linearization in the transformation from theoreticalmodel to simplified one. In order to solve this problem , the simplified measuring model of Kappa number iscombined with the adaptive neural-fuzzy inference system (ANFIS) to build a fusion model for the on-line measurementof Kappa number. After the sample training , the proposed fusion model is of good stability and high precislon.

Key words: pulp, Kappa number, on-line measurement, mathematical model, diffuse reflection spectrum measurement, "tri -wavelength", model