Voith High Efficiency HM Rotor Energy Data, A Repulper Rotor Design Case Study

Abstract

A recently completed demonstration project, funded partly by the Wisconsin Focus on Energy program and Wisconsin Public Service Corporation, shows the effectiveness of an energy efficient repulper rotor design compared with that of a conventional rotor. We conducted a demonstration to measure the performance and energy consumption of the energy efficient virgin pulp repulper of Wausau Paper in Rhinelander, Wisconsin. This paper describes the demonstration setting, shows the analysis, and discusses the results. Careful monitoring of the batch repulping operation gave us a very good picture of the energy savings. We monitored the energy use and impact on pulp quality under the following three conditions: 1. The existing conventional repulping blade (HOG rotor) 2. A new conventional repulping blade of the same style (spare HOG rotor) 3. A new energy efficient repulping blade (HM rotor) The HM rotor, a tall, swept-back blade design, has been engineered to provide effective turbulence of the fiber suspension and maximum rotor-fiber contact while consuming low horsepower.