| Sludge and fly ash are common solid wastes. To find a way to dispose of them is becoming a central issue, which is related to the ecosystem security and human sustainable development. In this thesis, novel filter media-sludge fly-ash ceramic particles (SFCP) were developed by employing dewatered sludge, fly ash, and clay. SFCP were used in an upflow lab-scale A/O Biological aerated filter (BAF) and anaerobic filter (AF), respectively, to mainly investigate their feasibility, applicability, potential advantage and substitutability for wastewater treatment. According to the results, novel media could achieve a "win-win" goal by treating wastes with wastes and obtain the significant environmental, social and economic benefits.Compared with commercial ceramic particles (CCP), higher total porosity, larger total surface area, lower bulk and apparent density for SFCP were found. SEM showed that rougher surface of SFCP distributed with large pores was represented clearly, which were more beneficial to the immobilization of microorganisms if they were utilized as filter media. In addition, the tests of heavy metal content in lixivium of SFCP indicated that no heavy metal contents in lixivium were higher than thresholds determined by GB 5085.3-2007. Thus, this novel media had a stable performance, which would not cause secondary pollution and was safe for wastewater treatment.SFCP were employed in an upflow lab-scale A/O BAF to determine the best parameters for synthetic wastewater treatment. The optimum operation conditions were obtained as HRT of 2.0 h, A/L of 15:1 and 200% recirculation. Under the optimal conditions,90% CODcr, more than 98% NH4+-N and approximately 70% TN were removed. The functional zones of the reactor affected the removal of CODcr, NH4+-N and TN significantly, which resulted in some different but regular variation.Two lab-scale upflow AF packed with SFCP and CCP were employed to investigate the potential advantage and substitutability of the former for wastewater treatment. The results were listed as follows:SFCP reactor had an advantage over CCP reactor in terms of TN removal at the optimum C/N ratio of 4.03 when different volumetric loading rates were applied.During the restart period, nitrate was removed completely at the C/N ratio of 3.5; SFCP represented a relatively weak performance in nitrate removal compared with CCP, but this difference would disappear gradually with the increase of the C/N ratios. At lower C/N ratios, nitrite accumulation (NA) was obvious and was affected greatly by HRT; while the process of dissimilatory nitrate reduction to ammonia (DNRA) had some negative influence on nitrate removal only when the C/N ratio was very low. Lower NA was observed in the SFCP column, especially when the C/N ratio was more than 3.5. NA disappeared when the C/N ratio was more than 5.0, corresponding to the maximum TN removal; TN could not be removed completely due to the process of DNRA; Orthophosphate uptake also took place in the restart performance; P removal increased with the increase of the C/N ratios, especially when the C/N ratio was beyond 3.5; The maximum value (about 55%) was achieved at the C/N ratio of 5.0, which agreed well with the TN removal. SFCP reactor indicated a better performance in TN and P removal compared with CCP reactor. In addition, the microorganism group presented layered characteristics with the column height, and the zonation of P removal was clearer than that of TN removal. Biofilm was mainly distributed at the height of 25 cm from the column bottom, which suggested that bacteria structure during the restart period did not change obviously compared with that during the start-up period.When the C/N ratio of 2.60 was applied, a linear correlation between HRT and nitrite accumulation ratio was observed, which was more obvious in the CCP column; Due to incomplete nitrate conversion, the linear correlation between HRT and TN removal was relatively weak. Under different HRT, SFCP reactor kept a stronger inhibition of NA.When no external nitrogen resource was spiked, the structure of bacteria group was varied. P-uptake bacteria were replaced by heterotrophic anaerobe; the profile was like "U". The process of DNRA became stronger and stronger with the increase of the C/N ratios; when the C/N ratio was more than 30, a line correlation between C/N and DNRA was found.During the start-up and restart period of AF, SFCP represented a higher performance in TN and P removal. Therefore, it could be concluded that SFCP had a potential advantage and substitutability for CCP, which was a very promising filter media.
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