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This study investigated the characteristics of SSA in Taiwan area. The potential applications of SSA reuse were also evaluated. Four major characteristics of SSA, including chemical compositions, pozzolanic properties, physical properties, and surface properties were analyzed. Experimental results found that SSA was a complex mixture of burnt residues of sludge biomass and minerals. The major chemical compositions of SSA were silicon oxide, aluminium oxide, and iron oxide. The most predominant silicon oxide occupied 41.3 to 56.1% of overall SSA weight and approximately 60% weight of silicon oxide in SSA was amorphous type. Due to the effect of amorphous silicon oxide, the SSA exerted pozzolanic activity. The strength activity index (SAI) value of SSA was between 53.6 and 74.3%. The SSA particles were also the agglomeration of finer grains between 0.1 and 1μm of size. Therefore the SSA was porous with irregular particles with significant pore surface area. Additionally, the SSA exerted negative surface charge and cation-exchange capacity in neutral aqueous phase. Based on the SSA characteristics found in this study, four potential applications of SSA reuse were evaluated. These technologies included reusing as fine aggregate, reusing as pozzolanic material, melting or vitrification treatment, and reusing as adsorbent. In addition, the advantages and disadvantages of the above potential applications of SSA were discussed.

The potential advantages of the UV/H2O2 process treating petrochemical wastewater as the tertiary treatment or the direct pre-treatment were demonstrated. While the high alkalinity of wastewater was not reduced, the UV/H2O2 process as the tertiary treatment could not obtain removal efficiency of wastewater. If the system pH adjusts to 3, this process will polish the effluent of the current biological process to meet the National Effluent Standards of 1998. The results of the direct pre-treatment with the UV/H2O2 process revealed that the recalcitrant compounds presented in raw wastewater would be destroyed to small molecules and might reduce some degree of activity inhibition to bioculture. In the detoxified investigation of spiking aromatic compounds, this process could obtain a good removal efficiency, including a lot of COD removal and the complete detoxification.

Inoculation of pure microbial culture to biodegrade recalcitrant organic compounds has had increased interest in the field of biological treatment of polluted waters or wastewater effluents. The removal of benzo(a)pyrene by the free cells of Phanerochaete chrysosporium strains, including ATCC 24725, ATCC 32639, and ATCC 34541, in a shaking vessel with a nitrogen-limited incubation medium was observed. This study also investigated the removal efficiencies of naphthalene, fluoranthene, and benzo(a)pyrene by immobilized white-rot fungus in a shaking flask and an aeration batch bioreactor. The biocarrier used in this investigation was a mixed gel composed of alginate and powdered activated carbon (PAC). The results showed that these polycyclic aromatic hydrocarbons (PAHs) were removed with an increased rate during the stationary growth phase, and strain ATCC 24725 exhibited the best PAH removal efficiency. No PAH residuals could be detected by HPLC from the immobilized-cell cultures in the shaking flask or aeration bioreactor during the incubation. However, a likely metabolite of PAH was identified in the chromatogram. The alginate-PAC biocarriers presented availability accessible pore volume for the colonization of fungus mycelia, moreover, the PAC fraction of the biocarrier obviously affected adsorptive capacities of PAHs.

The textile industry, which produces toxic and low biodegradable wastewater, is a major industry of Taiwan. Thus, this study compared the performance of the membrane bioreactor (MBR) and sequencing batch reactor (SBR) process for treating real textile dyeing wastewater. The microbial diversity of the MBR process was also identified by a combined culturing method and molecular biotechnology. The results show that the removal efficiencies for color, COD, BOD, and SS with the MBR process were 54, 79, 99, and 100%, respectively, all higher than the corresponding parameters for the SBR process: 51, 70, 96, and 60%. All the above four parameters for the MBR effluent meet the criteria of the Taiwan EPA, while on the other hand for the SBR process, only color and COD meet the Taiwan EPA effluent criteria. Furthermore, the genus Microbacterium, especially the Microbacterium aurum, was the most predominant population, contributing 70.6% of the total isolates, and might be responsible for the degradation of the dyeing wastewater. Another two textile dyeing degradation bacteria, Paenibacillus azoreducens and Bacillus sp., as predominant bacteria in MBR sludge, were also observed.

The potential advantages of the UV/H 2 O 2 process treating petrochemical wastewater as the tertiary treatment or the direct pre-treatment were demonstrated. While the high alkalinity of wastewater was not reduced, the UV/H 2 O 2 process as the tertiary treatment could not obtain removal efficiency of wastewater. If the system pH adjusts to 3, this process will polish the effluent of the current biological process to meet the National Effluent Standards of 1998. The results of the direct pre-treatment with the UV/H 2 O 2 process revealed that the recalcitrant compounds presented in raw wastewater would be destroyed to small molecules and might reduce some degree of activity inhibition to bioculture. In the detoxified investigation of spiking aromatic compounds, this process could obtain a good removal efficiency, including a lot of COD removal and the complete detoxification.