Novel Drainage Analysis of Chemical Additives in Systems with Increasing Mill Closure, 1996 Papermakers Conference Proceedings

A growing desire for increased productivity from linerboard mills has placed a premium on the analysis of drainage performance of chemical additives. Traditionally, uses of wet-end chemical additives have served as strength, sizing, retention, and drainage aids. These additives have been very successful in virgin or recycled fiber furnish with open water systems, however, often similar results are not observed with closed water systems. We have developed a very accurate and rapid system for measuring the drainage performance of wet-end additives. The use of a Turbulent-Pulse Sheet Former (1) that has been integrated with a computer by software developed in house allows for a variety of useful drainage parameters to be measured. Handsheets that are prepared during the drainage analysis allow a correlation with strength performance to be made. Comparisons of the results using this technique on representative open and closed systems demonstrate differences in chemical additive performance. Methods for the laboratory simulation of furnish from virgin and recycle pulp with varying degrees of mill closure have been developed based upon the chemical and physical characterization profiles of many varied board mills. With these innovative drainage-testing and stock simulation methods, the analyses of chemical additives in a wide array of furnishes with varying degrees of water system closure is possible.