Development and Application of a New Laboratory Method for Measuring Retention, 2005 Papermakers Conference

Influential factors, such as additives, process temperatures, shear forces and contact times with chemicals. A detailed laboratory analysis of all relevant parameters is indispensable in order to optimize retention and drainage and thus to improve both PM runnability and paper quality. Hitherto, these analyses have been very time-consuming and labour-intensive. In 1999, PTS launched a research project focusing on retention in the paper machine which was aimed at developing a new laboratory method for adequate simulation of the PM process conditions of drainage and retention. Among others, the project was to yield a test setup allowing a greatly accelerated determination of retention and drainage. The paper industry – i.e. the former BTG Pulp & Sensors in Säffle, Sweden, and Mütek BTG GmbH in Herrsching, Germany - supported the project by providing measuring equipment. The above companies that have merged in the meantime, used the findings of the above PTS project to design a new measuring system - the DFR 04 - which is described in detail in the second part of this paper. In addition, the presentation gives an overview of customary methods of measuring retention, dewatering and freeness and outlines the principle of consistency measurement by the Peak Method as applied in the DFR 04.