| A large amount of sludge with complex component is produced in water supply plant and the urban sewage disposal plant, which should be treated and disposed to protect from secondary pollution and to ensure the treatment effect. So how to make an economical, effective use of it has recently become one of the increasingly concerning issues in environmental science. Media is the factor of the attached-growth process, which performance directly influences and restricts the efficiency of the process. Sludge media is the combination of the resource reuse of the sewage sludge and the sludge of water supply plant, solid burning technology and biofilm process. The optimal sintering process, the selecting of additive and the physical and biological properties of sludge media is studied in this paper. The research on sludge media's best prscription of aggregate and additive is conducted through the contrast and orthogonal tests. The condition of the sintering process is also determined. Sludge media consists of the sewage sludge, the sludge of water supply plant and Zhenjiang clay。Limestone, active carbon powder and braize is respectively used as the additive of sludge media. Based on the greatest difference analysis and the variance analyses of physical indexes of media, such as apparent density, it shows that limestone, active carbon powder and braize make against the expansion of the sludge media. It also shows that No.4 media at the second phase is better than others in the physical properties of apparent density. Through the analysis of the function of primary chemical contents in the sintering process, porosity formation mechanism and the experimental sintering process, we get the optimal sintering process. Then a compararative experiment of three types of media, which are media of best prescription accordingto the result of preceding experiment, ceramic granular and plastic floating packing, was taken respectively to demonstrate the superiority of sludge media on physical characteristic and biofilm attachment. The result shows that at different HRT and different temperature the removal efficiency of the CODcr and NH3-N of sludge media is better. When the inflow CODcr are 272413mg/L and the inflow NH3-N are 50.9769.30 mg/L, the efficiency is 83.78%96.70% and 54.49%98.46% respectively. Compared with other two media, the maximum of biomass attached on the sludge media is respectively 4.2 times of ceramic granular and 1.4 times of plastics floating packing. So it is feasible to be biofilm carrier for sludge made of sludge. In conclusion, No.4 media at the second phase is ideal for wastewater treatment and it consists of Zhenjiang clay (10%), sewage sludge which water content is 80% (40%) and the sludge in water supply plant (50%).
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