LIUJing,TIANYi-mei,LIUYun-hui,et al.Investigation of Chromium Release Dynamics in Water Supply Pipelines[J].China Water & Wastewater,2024,40(23):40-48.
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Investigation of Chromium Release Dynamics in Water Supply Pipelines

China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU] volume: 第40卷 Number: 第23期 Page: 40-48 Column: Date of publication: 2024-12-01
Author(s):
LIU　Jing1;  TIAN　Yi-mei1;  LIU　Yun-hui1; 2;  PENG　Zhu1;  SHEN　Hai-liang3;  JIA　Shi-chao1
（1. School of Environmental Science and Engineering， Tianjin University， Tianjin 300350， China； 2. North China Municipal Engineering Design and Research Institute Co. Ltd.， Tianjin 300110， China； 3. Computational Hydraulics International， Canada）
Keywords:
water supply pipelines;  chromium release;  steady water;  bulk water;  occluded water
Abstract:
This study focuses on the corrosion scale and water present in actual drinking water pipelines. The presence of heavy metals within the corrosion scale was investigated, the release behavior of chromium (Cr) from pipeline corrosion scale was analyzed, and the impact of varying water quality environments on Cr release at different locations within the pipeline was examined using a dynamic pipeline circulation device. Heavy metals such as chromium (Cr), arsenic (As), and lead (Pb) were detected in all layers of the pipe scale, with concentrations diminishing from the surface layer to the underlying loose porous layer. The two-constant kinetic model effectively characterized the Cr release process from the pipe scale, while the Elovich kinetic model demonstrated a secondary fitting performance. This suggested that the surface of the pipe scale exhibited a significant degree of heterogeneity, indicating that the Cr release process was relatively intricate and that the initial release rate showed a positive correlation with heavy metal concentrations within the corrosion scale. Based on the hydraulic simulation results from ANSYS, the water within the pipeline was categorized into three distinct types: bulk water, steady water, and occluded water. Under identical water quality conditions, the sequence of chromium release from highest to lowest was as follows: steady water, bulk water, and occluded water. The water quality exhibited comparable effects on Cr release at various locations within the pipeline. Conditions characterized by low pH, elevated water temperature, and high SO42- concentration facilitated the release of Cr. Furthermore, the hydrodynamic shear stress expedited the release of Cr within the pipeline.
Last Update: 2024-12-01