Effects of suspended particles on TP, TN, CODMn concentrations in the Three Gorges reservoir

In order to study the effects of the suspended particles on water quality in the Three Gorges reservoir, the relationship between suspended particles and nutrient pollutants, that is total phosphorus (TP), total nitrogen (TN), chemical oxygen demand (CODMn) in the Three Gorges reservoir and the two tributaries of the Yangtze river flowing into the reservoir were studied in two steps: synchronous monitoring in the field and the laboratory experiments. Adsorption equilibrium and adsorption kinetic experiments were carried out using two groups of suspended particles: particle size of 8-20 mu m and particle size of less than 8 mu m. The synchronous monitoring, results on seven cross-sections show that there is strong relationship between the suspended particle concentration and the concentrations of the following pollutants: particulate phosphorus (PP), particular nitrogen (PN), and particulate CODMn. The results from adsorption equilibrium experiments show that the experimental data can fit well in Langmuir isotherm equations. Particle concentration and particle size remarkably affected equilibrium adsorption amount. The experimental data from phosphorus adsorption kinetics provide a good fit in a second-order model.