Notice of Retraction: Comparison Study on the Efficiency of Treating Rural Domestic Wastewater with Water Hyacinth Pond, Facultative Pond and Alga/Duckweed Pond

Abstract

Waste stabilization pond has been used to treat wastewater from 1901, and has been modified into some kinds of new type ponds, such as water hyacinth pond and duckweed pond, or combined ponds. In this paper, comparison study on treating rural domestic wastewater with water hyacinth pond, facultative pond and alga/duckweed pond was carried out and the performance differences of wastewater treatment with this three kinds of ponds were found out. The results showed that water hyacinth does not pose significant influence on the acid-base balance in the water. pH value in the water hyacinth pond is stable, varies within the range from 6.50 to 7.16, slightly acid due to the metabolism and acidification of the organic matter. While facultative pond and alga/duckweed pond have higher pH value that is bigger than 7.5, and the alga/duckweed pond has a fluctuation above 8.5 for the reason that CO2 in the water is utilized in the photosynthesis. It is concluded, compared with facultative pond and alga/duckweed pond, that the wastewater treatment efficiency of water hyacinth pond is outstanding. The water hyacinth pond has better removal efficiency for organic compounds, nitrogen, and phosphorus. The ranking of the three kinds of ponds in organic compounds removal efficiency is: water hyacinth pond >; facultative pond >; alga/duckweed pond; for nitrogen removal efficiency: hyacinth pond >; alga/duckweed pond >; facultative pond; for phosphorus removal efficiency: hyacinth pond >; alga/duckweed pond >;facultative pond.