Removal of low-concentration phosphorus by efficient phosphorus removal composite-based ecological floating beds

In order to strengthen the effect of ecological floating beds on the removal of low-concentration phosphorus (P) in water, the efficient P removal composite (EPRC), which is a high-efficiency P removal material developed in the current work as the substrate for the Ipomoea aquatica floating beds, was introduced into the solar chamber. The EPRC dosage (2g/L) and the optimal number of Ipomoea aquatica plants (6 plants/10 L) suitable for the floating beds were determined experimentally. Results revealed that EPRC and Ipomoea aquatica composite floating beds had the best P removal effect among the three floating beds. Moreover, the root growth ratio of Ipomoea aquatica in the composite floating bed and the plant-only floating bed was 1.90 and 1.25, respectively. The stem growth ratio of Ipomoea aquatica in the composite floating bed and plant-only floating beds was 1.54 and 1.21, respectively. The leaching experiments showed that the leaching of heavy metals from the EPRC was negligible.