Research on the Phosphorus Removal Mechanisms and Approaches in Various Horizontal Subsurface Flow Constructed Wetlands

Abstract:

This research studied that performances and mechanisms of phosphorus removal in three types of HSFCW: reed/gravel bed system (W1), multiple plants/gravel bed system (W2) and reed/multiple substrates bed system (W3). Spatial distribution and fractionation analysis of phosphorous in different substrates showed that the accumulated phosphorous in gravel, zeolite and steel slag were mainly in forms of Ca/Mg-P, residual-P and Fe/Al-P respectively. Biomass and phosphorus contained in plants harvested in early autumn was obviously higher than that contained in plants of late autumn, so the optimal harvest time should be late October. Among three systems, the phosphorus removal by adsorption and sedimentation of substrates accounted for 67%-76% of the total phosphorous removal and was the major channel for phosphorous removal. Removal by harvesting plants ranked second, accounting for 15%-21%. Other removal mechanisms accounted for about 10%. The research reveals that W3>W2>W1 in phosphorus removal efficiency in HSFCWs.

• Periodical: Advanced Materials Research (Volumes 573-574)
• Pages: 599-604
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.573-574.599
• Online since: October 2012
• Authors: Zhi Ru Tang, Yue Wen, Qi Zhou
• Keywords: Horizontal Subsurface Flow Constructed Wetlands (HSFCWs), Multi-Plants System, Multi-Substrates System, Phosphorus Removal, Substrate Adsorption

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