| Abstrakt: |
Lack of knowledge on phosphorus transport and retention in soils amended with polyaluminium chloride and anionic polyacrylamide water treatment residuals (PAC-APAM WTRs) makes it challenging to effectively utilize these materials as amendments in traditional soil-based media for stormwater bioretention systems to mitigate phosphorus pollution. This study investigated the impact of initial phosphorus concentration (C0), pH, and flow rate on phosphorus transport and retention in columns of three soil types amended with PAC-APAM WTRs under saturated hydraulic conditions. Results demonstrate that increasing C0 led to a decrease in the retardation factor (Rf) from 30.05 to 26.87, 12.64 to 9.10, and 12.27 to 6.68 in Soil 1 and PAC-APAM WTRs columns, Soil 2 and PAC-APAM WTRs columns, and Soil 3 and PAC-APAM WTRs columns, respectively. Similarly, increasing flow rate resulted in a decrease in Rf from 22.81 to 9.01, 11.14 to 4.74, and 16.13 to 7.57 in the respective columns. The adsorbed phosphorus mass per gram of media increased from 6.4 to 7.2 in Soil 1 and PAC-APAM WTRs columns and 7.6 to 9.8 in Soil 2 and PAC-APAM WTRs columns with increasing C0, but decreased from 16.3 to 8.0, 11.0 to 5.3, and 8.7 to 4.8 in the respective columns with increasing flow rate. No obvious trend was observed regarding the impact of pH on Rf and the adsorbed phosphorus mass. Future research should aim to elucidate the underlying mechanisms governing the comprehensive effects of C0, pH, and flow rate on phosphorus transport under field conditions. [ABSTRACT FROM AUTHOR] |
Full text from SpringerLink