用于城市景观水体悬浮物去除的菱形管沉淀结构模拟研究

Simulation study of rhombic pipe sedimentation structures for removal of suspended solids in urban landscape water bodies

摘要

【目的】菱形管沉淀结构已有效应用于水厂、水库的水污染治理，但其在悬浮物(SS)污染的城市景观水体原位治理中的利用效率并不明确。为探究菱形管沉淀结构在不同SS污染水体状况中的结构参数和效率的关系，【方法0除效率选择菱形管结构参数。【结果】结果显示：在SS浓度和SS粒径因素分别主导的水污染情景下，40 mm管径和2 000 mm管长的菱形管结构去除效率均最佳，平均去除率分别为87.3%和75.4%,去除效率随进水SS浓度及粒径的增大而提高；去除效率与管内速度场均匀性呈较强的正相关性，与管道堵塞呈中等负相关性。【结论】结果表明：在波动的进水水质状况下，40 mm管径和2 000 mm管长的菱形管结构对SS去除效率具有良好的稳定性，验证了菱形管沉淀结构在城市景观水体原位治理中的高效应用潜力。

Abstract

[Objective] Rhombic pipe sedimentation structures have been widely used for water pollution treatment in water plants and reservoirs. However, their utilization efficiency in the in-situ treatment of urban landscape water bodies polluted with suspended solids(SS) remains unclear. The aim is to explore the relationship between structural parameters and efficiency when rhombic pipe sedimentation structures are applied to water bodies with different levels of SS pollution. [Methods] Two structural parameters of the rhombic pipes—pipe diameter and pipe length—were selected, and 9 geometric models of rhombic pipes were established. Two inflow variables, SS concentration and SS particle size, were set to form five different wastewater scenarios. Computational Fluid Dynamics(CFD) software was used to conduct solid-liquid two-phase flow numerical simulations, and field tests were set up to calibrate the model-solving parameters. The rhombic pipe structural parameters were selected based on removal efficiency. [Results] The result showed that under water pollution scenarios dominated by SS concentration and SS particle size, the rhombic pipe structure with a 40 mm diameter and 2 000 mm length achieved the highest removal efficiency, with average removal rates of 87.3% and 75.4%, respectively. The removal efficiency increased with rising SS concentration and particle size in the influent. Additionally, removal efficiency exhibited a strong positive correlation with the uniformity of velocity field inside the pipes, and a moderate negative correlation with pipe clogging. [Conclusion] The result indicate that under fluctuating influent water quality conditions, the rhombic pipe structure with a 40 mm diameter and 2 000 mm length demonstrates strong stability in SS removal efficiency, validating its high potential for efficient application of rhombic pipe sedimentation structures in in-situ treatment of urban landscape water bodies.

关键词

数值模拟 / 城市景观水体 / 菱形管结构 / 悬浮物 / 去除效率

Key words

numerical simulation / urban landscape water bodies / rhombic pipe structure / suspended solids / removal efficiency

基金资助

国家水体污染与治理科技重大专项(2018ZX07105-002)

中央部门预算项目(WE0161A042024)

水利部重大科技项目(SKS-2022071)