Development of centrifugal slurry pumps in tailings disposal and comparison with positive displacement pumps

Abstract

This paper covers FLSmidth KREBS® pump development, over the past 10 years, of an extensive range of highpressure centrifugal slurry pumps for multistage applications. The primary objective has been to produce safe, economical, energy efficient and maintenance friendly centrifugal slurry pumps to fulfil the expanding requirements of the mineral processing industries in the long distance transportation of tailings and mineral slurries. Two ranges of pumps have been developed, a double cased pump (based on the KREBS rubber lined slurryMAX™ XD pump) and an unlined white iron cased pump (based on the millMAX™ pump). The logic behind the development of the two pump ranges will be explained in depth covering the design and first article production, getting it right. The methodology of the hydraulic and structural criteria requirements that are considered during the pumps’ design are integrated with the use of computational fluid dynamics and finite element analysis to ensure that the pumps perform safely, reliably and with maximum efficiency. Application of the pumps to projected operating data is explained taking into consideration specific needs for flange and foundation loads, maintenance and condition monitoring. Consideration of slurry rheology and its implication on pumping performance is discussed. Cost comparison between actual field data and the theoretical positive displacement (PD) costs, as presented at the 21st International Seminar on Paste and Thickened Tailings, will be analysed in the Appendix.