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This study was conducted to evaluate the stability and performance response under short-term hydraulic and organic shock load conditions in temporal and spatial phase separated process. The overall removals of BOD, TN, and TP declined slightly despite the hydraulic shock loading, and rapid recovery could be observed again after four cycles of 16 h. It seems that rapid recovery may be achieved by the unique characteristics of the system operated in a fed-batch manner. The effect of shock load on nitrogen removal due to increment of flow rate was higher than that of phosphorus, because of the insufficient reaction time for the nitrification and denitrification. After the organic shock, however, recovery time for phosphorus removal was needed rather than that of organics and nitrogen, because the overload to micro organisms related to the phosphorus release is attained by short-term organic shock loading.

In this study, a cost-effective and eco-friendly route for removal of phosphate in wastewater was demonstrated using an Al alloy foam filter with a mesoporous aluminum hydroxide (Al(OH3) film. The mesoporous Al(OH)3 film on which the ion exchange and adsorption of phosphate occur was generated using a simple alkali surface modification process. For higher phosphate removal by the surface-modified Al alloy foam filter, the number of filters was increased up to 20, which achieved 90% phosphate removal within a very short contact time. As a recycling process, a second alkali surface modification was applied to the used filter after phosphate adsorption. It clearly indicated that the used filter can be recycled via a second alkali surface modification due to the ion exchange mechanism. It was shown that an alkali surface-modified Al alloy foam filter is a powerful candidate for phosphate removal in water treatment facilities.

An innovative phosphorus removal filter made of silica granules was designed and evaluated for advanced wastewater treatment. The silica granules from natural mineral stones were formed into a porous body by sintering with addition of glass powder. The phosphorus was removed by the ionic exchange mechanism between OH− in Si(OH)4 and PO43− in wastewater. The silica filter was very effective in removing phosphorus in wastewater by ion exchange. We found the possibility of a phosphorus removal filter with no sludge production characteristics of flocculation treatment techniques, and it seems to be quite meaningful as a new wastewater treatment.

The objective of this research is to draw the optimal cycle length and evaluate the effect of the fraction of anoxic and anaerobic phases in a cycle maximizing the nutrients removal in a modified temporal and spatial phase separated process. A pilot-scale system operated at HRTs of 10–21 h, SRTs of 16–34 d, cycle times of 2–8 h, and mixed liquor temperature from 9 to 30 °C showed average removals of BOD, TN, and TP as high as 93, 79, and 86%, respectively. Higher nitrogen removal could be achieved for shorter cycle time, while better phosphorus removal could be accomplished for longer cycle time. Optimal cycle time for simultaneous removal of nitrogen and phosphorus conflicted with each other. The effect of ratio of cycle time to system HRT on system performance was also shown to have the same tendency as that of cycle time. Higher TN removal of phased isolation technology could be achieved relative to that of SBR as the cycle length became longer in the same HRT. As the fraction of anoxic/anaerobic phase in a cycle became larger, the removal efficiency of TN and TP simultaneously decreased because of the discharge of untreated ammonia nitrogen and released phosphorus.