| dc.description.abstract | The study found that the content of SiO2 in different sewage sludge ash affects the bloating effect of aggregates in the specific sintering temperature (1,050℃～1,150℃), and the glass phase material of SiO2 further dominates the lightweight effect during the sintering process. The porosity and volume expanding rate of aggregates increase as the content of the glass phase materials in the sewage sludge ash increases under sintering in the specific temperature. However, the density and compression resistance are reduced at the same moment. In other hand, the crystal SiO2 in sewage sludge ash have negative influence on the bloating effect of aggregates. This is because sufficient Amorphous SiO2 material is needed to trap gaseous bubbles in order to enhance bloating effect. Additionally, except the phrase change of SiO2, there are several factors affecting the bloating effect of aggregates. The factors include sintering temperature, the content of crystal and amorphous phase material, and the flux. We could also reduce the sintering temperature or diminish the bloating effect of aggregates by adding crystal and glass, incinerated ash or etc to adjust the composition of the sewage sludge ash. However, sintering temperature is still the most crucial factor for controlling the bloating effect.
After the evaluation of the efficiency of turbidity removal, as for non-broken-sintered-filter by sintering time in 10min. and sintering temperature at 1,125℃, the filtration performance equal to the sand filled in the 10cm filter bed nearly. The optimum substitution ratio to sand was 25%. Sintered under the same conditions but crumbled artificially later, broken-sintered-filter improved the decreasing efficiency of turbidity removal into upwards, extending the filter run.In conclusion, the sintered filter reveals its potential to substitute the sand as the filter media of the deep bed filtration according to the properly physical and chemical characteristics, and the competence of turbidity removal. | en_US |