Effektoptimering av pumpsystem med massasuspensionsflöden

Abstract

An optimization of the power consumption of six pumps in the screening system of Hylte Mill's TMP plant is conducted. The calculations are done with a model for pressure drop in pipe systems, given in a calculation instruction for pipe friction losses for pulp. Used calculation model is also tested versus experimental values from the literature, in order to examine the validity. Compared to literature data, the model seems to give somewhat high pressure drop for TMP suspensions. There is a lack of experimental data for mechanical pulps and studied graphs date back to the 1970's. Measured values from the TMP plant are tested versus theoretical pressure and power of the current pumps. A good agreement between measured and theoretical values is noticed. A reduction in power consumption of 150 kW seems very realistic by minimizing the pressure reduction over the control valves and with the installation of speed controlled pumps in studied system. This corresponds to 44% of today’s power consumption. All studied pumps show clear saving potential, although the required pressure is overestimated. None of the suggested pumps is limited by the start-up resistance. An Excel based program for automatic pressure calculations in a pipe system and with graphical pressure drop representation, has been developed. A basis for further development of a program based pressure drop calculation and graphical technique is given, partly through the developed program, partly through suggestions given in the report.