Author(s): D X Ye; H Li; X D Lai

Linked Author(s):

Keywords: CFD simulation; Degas process; Medium consistency pump; Gas-liquid two-phase flow; RNG k-ε turbulence model

Abstract: The principal of this work is to simulate the degas process and study experimental performance of medium consistency pump. Based on the actual running performance of the MC pulp pumps, the gas-liquid two-phase flow in the pulp pump was numerically simulated, adopting the Eulerian gas-liquid two-phase flow model and the RNG k-ε turbulence model. The gas-liquid separation and the gas exhausting process were verified based on the gas-liquid distribution inside the turbulence generator and the pump impeller. The impacts of the standpipe liquid level and the vacuum degree of the vacuum pump to the gas discharging effects were studied. The optimal standpipe liquid level, 5.5 m, the critical standpipe liquid level, 3.8 m, and the critical degree of the vacuum pump, 0.2 atm, were defined and obtained from the simulation. Two methods were presented both enhance the gas discharging effect and decrease the flow loss from the suction hole of the MC pulp pump. A sonar flowmeter and monitoring system is used to experimental set up, and the performance characteristics of MC pump in different conditions were studied. The dimensionless analysis is applied to pulp pumping. The experimental results show that with vacuum degree increasing pump head increased and gas fraction decreased at pump outlet, and the maximum flow rate increases.

DOI: https://doi.org/10.1088/1755-1315/163/1/012007

Year: 2017