TY - JOUR
T1 - A numerical study on influent flow rate variations in a secondary settling tank
AU - Su, Junwei
AU - Wang, Le
AU - Zhang, Yumin
AU - Gu, Zhaolin
N1 - Publisher Copyright:
© 2019 by the authors.
PY - 2019/12/1
Y1 - 2019/12/1
N2 - The secondary settling tank is an essential unit for the biochemical treatment of domestic sewage, and its operational effect influences the quality of euent. Under the influence of the confluence of rainwater and sewage, wastewater use habits, etc., the inflow of the secondary sedimentation tank changes over time. In this paper, OpenFOAM, an open-source computational fluid dynamics package, was used to study the dynamic behaviors of solid-liquid two-phase flow in the tank under influent flow rate variations. A coupled method including a mixture model, drift equation and a dynamic boundary method is proposed. Numerical investigations were carried out for a 2D axisymmetric sedimentation tank using 12 cases. With increasing influent flow rate, sludge accumulates continuously in the bottom left side of the tank, sludge hopper, and inlet; the sludge blanket thickness near the right end of the tank increases continuously; and the sludge concentration in the tank approximately linearly increases with time, with a low slope. The developed framework is generic and is, therefore, expected to be applicable for modelling sludge sedimentation processes.
AB - The secondary settling tank is an essential unit for the biochemical treatment of domestic sewage, and its operational effect influences the quality of euent. Under the influence of the confluence of rainwater and sewage, wastewater use habits, etc., the inflow of the secondary sedimentation tank changes over time. In this paper, OpenFOAM, an open-source computational fluid dynamics package, was used to study the dynamic behaviors of solid-liquid two-phase flow in the tank under influent flow rate variations. A coupled method including a mixture model, drift equation and a dynamic boundary method is proposed. Numerical investigations were carried out for a 2D axisymmetric sedimentation tank using 12 cases. With increasing influent flow rate, sludge accumulates continuously in the bottom left side of the tank, sludge hopper, and inlet; the sludge blanket thickness near the right end of the tank increases continuously; and the sludge concentration in the tank approximately linearly increases with time, with a low slope. The developed framework is generic and is, therefore, expected to be applicable for modelling sludge sedimentation processes.
KW - Computational fluid dynamics
KW - Numerical simulation
KW - Secondary settling tank
KW - Solid-liquid two-phase flow
UR - https://www.scopus.com/pages/publications/85079680627
U2 - 10.3390/PR7120884
DO - 10.3390/PR7120884
M3 - 文章
AN - SCOPUS:85079680627
SN - 2227-9717
VL - 7
JO - Processes
JF - Processes
IS - 12
M1 - 884
ER -