NEW APPROACH TO THE MEASUREMENT OF PULP CONSISTENCY.

A new technique has been developed for measuring the average consistency of paper pulp flowing through a large steel pipe. Radio waves were propagated in a 6. 23-in. -diam. pipe. The effective dielectric constant was then calculated by measuring the wavelength, frequency, and attenuation of these radio waves. Pulp consistency can be determined by using the dielectric constant in conjunction with a mixing model and the cellulose density. Tests were carried out at the Institute of Paper Chemistry using known consistencies of commercial, short-fiber, bleached kraft pulp. Good agreement was obtained between the expected and measured values of pulp consistency.