Energy, environmental and financial evaluation of progressive cavity pumps with rotors produced from different materials

Abstract

In industrial applications, pumps traditionally operate for thousands of hours at high pressures, often under severe conditions imposed by abrasive fluids or undergoing chemical attack. However, in tinting dispensers, a progressive cavity pump (PCP) rarely reaches one hundred hours of use, and alternative materials could be explored for its components. An energetic, environmental, and financial assessment was conducted on four distinct materials intended for the rotor of a PCP: chrome-coated steel, PA6, PEEK, and 6082 aluminum alloy. Equipment was built to obtain the characteristic curves of each pump, electrical energy consumption, wear of rotors and stators, and energy efficiency. The rotor machining process was instrumented to measure electrical energy and inputs. The Cleaner Production method was applied, and, finally, the rotors underwent financial evaluation. There was no significant wear on the stator-rotor pairs, the minimum lifetime was not a challenge for the integrity of any of the components, and the polymers studied were not incompatible with the working fluid. Maximum and minimum energy efficiency of the pumps occurred with aluminum alloy and PA6 rotors, respectively, showing a difference of 22.5% in electrical energy consumption. However, the PA6 rotor presented the best energy and environmental efficiency in the manufacturing process, in addition to being the only one capable of dry machining. Financially, all proposed materials registered a significant improvement, particularly highlighting the aluminum alloy and PA6 rotors, which exceeded a 90% cost reduction.