Alkaline solubilization of excess mixed sludge and the recovery of released phosphorus as magnesium ammonium phosphate.

The alkaline solubilization of excess mixed sludge was investigated and subsequently the released phosphorus was recovered as magnesium ammonium phosphate (MAP). Considerable and rapid release of glycogen and protein was encountered after alkaline addition into the sludge. Only 45.

[Response of Algae to Nitrogen and Phosphorus Concentration and Quantity of Pumping Water in Pumped Storage Reservoir].

Taking a pumped storage reservoir located in southern China as the research object, the paper established a three-dimensional hydrodynamic and eutrophication model of the reservoir employing EFDC (environmental fluid dynamics code) model, calibrated and verified the model using long-term hydraulic and water quality data. Based on the model results, the effects of nitrogen and phosphorus concentrations on the algae growth were analyzed, and the response of algae to nitrogen and phosphorus concentration and quantity of pumping water was also calculated. The results showed that the nitrogen and phosphorus concentrations had little limit on algae growth rate in the reservoir.

[Status analysis of nutrients and eutrophication assessment in Shenzhen coastal waters].

Based on the field data of Shenzhen coastal water quality in 2002-2007, variation characteristics of nutrients including NH4+ -N, NO3- -N, NO2- -N, PO4(3-) -P and DIN were presented. And the correlationships between nutrients and pH, salinity were also investigated. Furthermore, eutrophication index (E), organic pollution index (A) and potential eutrophication were employed to assess the eutrophication degree of Shenzhen coastal waters.