Study on performance characteristic of medium consistency pump

Abstract

The aim of this work is to study the operation and performance characteristics of medium consistency pump in different conditions, and a sonar flowmeter and monitoring system are used in the experimental set up. The head, efficiency, gas fraction, and max flow rate were studied under different pulp concentrations 7.52%, 9.3%, and 12.1%; at speeds 960, 1140, and 1500 r/min; and degas vacuum degree. The dimensionless analysis is applied to pulp pumping. The experimental results show that pump head and efficiency decrease with the increase in the pulp concentration at constant flow rate. Vacuum degree has significant effect on pump performance. Medium consistency pump can pump pulp concentration at 7.52% without vacuum, but pump head and efficiency decrease obviously with the increase in the flow rate. With increase in vacuum degree, pump head increases and gas fraction decreases at pump outlet. Head increases with the increase in rotation speed. The higher rotation speed leads to the lower vacuum degree, which indicates that enhancing speed improves gas–liquid separation. With the increase in concentration of the gas fraction, the degas vacuum degree increases. The max flow rate decreases with the increase in concentration and increases with the increase in rotation speed.