Purification Effect of Ecological Floating Bed with Different Planting Density on Tailing Water

Abstract

This study aimed to determine the optimal planting density of floating bed plants for purifying wastewater treatment plant tailwater and realizing the resourceful use of wastewater. Three commonly used floating bed plants, Iris, Zelkova, and water onion, were selected, and a self-designed and assembled floating bed frame was used as the plant carrier. Simulated wastewater treatment plant tailwater was treated for 28 days, and the pH value, chemical oxygen demand (COD), NH4 + −N, TN, TP, and plant growth were continuously monitored. The results showed that the best water purification effect was achieved when the planting density was 67 plants/m 2 . Thalia dealbata and Scirpus were found to have better TN and NH4 + −N removal effects than Iris, while Iris had a superior TP removal effect compared to Thalia dealbata and Scirpus. Additionally, Thalia dealbata had a better COD removal effect than Iris and Scirpus. Therefore, the optimal planting density for constructing an ecological floating bed was determined to be 67 plants/m 2 .