The effect of long-term fertilizer on total P,valid P,year-and-profile P composition,the property of P absorption and desorption of the soil,the index of P requirement of the soil,and so on,were studied,with the soil treated by CK,N,NPK,NPKM,NPKS,M in the long-term fertility-assessed experiment.

Determination of oxygen demand for high-load activated sludge process of treating city wastewater

Based on the calculation made by the model, total oxygen demand for the section from Beixinjing to estuary is calculated to be 24.

Analyze the influencing factors and calculate means of the sludge concentration identification of mixtures in aeration tanks,then deduct the theoretical calculation formula of the sludge concentration in mixtures on the relationships between oxygen tranasfer velocity and the oxygen demand in aerations.