Abstract
Abstract
This study deals with the effect of some operational parameters on the removal efficiency and behavior of duckweed based wastewater stabilization ponds. The results of the study showed that; covering the oxidation ponds with duckweed improve their ability to treat higher organic and nitrogenous loads. In addition, there is a relationship among the hydraulic detention time and each of the removalefficiency of organic and nutrients. Decreasing the hydraulic detention time decreases the removal efficiency of organic.On the other hand, the results of research also showedthat; increasing nitrogen and phosphor load leads to decrease removal efficiency of nitrate, nitrite, and phosphate, and increases removal efficiency of ammonia. Temperatures have also impact on the organic and nutrients removal and the concentration of dissolved oxygen in effluent. Highest removal and dissolved oxygen concentrations were recorded at the temperature of (26°C), and these values decrease with increasing or decreasing the temperatures.
Keywords: Duckweed; Stabilization ponds; Nutrient removal; HDT;Temperature
