Cause and Solution of Current Climbing in Axial Flow Pump in WWTP

When axial flow pumps are used in sludge reflux pump house of wastewater treatment plants or oxidation ditch process, the current will climb slowly after a period of operation and then the pumps can’t be used normally. The axial flow pump can be used normally in ideal fluid (clean water), but its hydraulic efficiency and shaft power are affected when used in viscous fluids (wastewater), because the impeller is sensitive to fluid viscosity and the hydraulic performance of impeller is mutable. In addition, the viscous flow has great rotation and vortex dispersion, which increases cavitation possibility and reduces pump efficiency, so that the motor load changes and the running current slowly climbs. In order to improve the cavitation resistance of the pump, under the premise of ensuring the performance parameters of the design condition, the high cavitation ratio speed model is selected by appropriately lowing the nD value to make the transformed pump run more stable, effectively extend the service life of the hydraulic components of the pump, and effectively expand the use range of the axial flow pump.