Energy conservation in controlled pump systems

Abstract

Industrial plants frequently employ oversized pumps, so that energy consumption may be unnecessarily high. Reductions are possible by determining the avoidable pressure drop caused by excessive control valve throttling. Ways are described to identify this avoidable pressure drop, based on data extracted from the plant. Utilising the data it is possible to lower energy consumption by choosing another pump, trimming the impeller, or alternatively switching to a variable speed drive. In the process industry, where the majority of centrifugal pumps have relatively low power ratings, trimming the impeller frequently turns out to be rather economical.