Treatment performance of metal membrane microfiltration and electrodialysis integrated system for wastewater reclamation

The integrated system with microfiltration/electrodialysis was proposed for wastewater reclamation. The filterability of metal membrane, membrane fouling reduction by ozonated water and the effect of operational parameters were experimentally investigated. Backwashing by ozonated water showed stable and effective + 3– membrane fouling reduction. The removal ratio of nutrients such as NH4 -N and PO4 -P concentration was about 96 and 94%, respectively, within 30 min of operation in the system. Proposed system showed good rejections on bacteria, suspended solids as well as ionic nutrients. Suggested wastewater reclamation system showed stable water quality during operational period over 6 months. Therefore, it is expected to be an effective and useful system for the reclamation of wastewater.

Water qualities of integrated system were investigated in a long-term operation over 6 months. The variation of effluent water qualities in a long-term operation was shown in Fig. 6. Average permeation flux, effluent water quality and rejection ratios were shown in Table 5 and average rejection ratio at each unit process was revealed in Table 6. Integrated wastewater treatment system using microfiltration and electrodialysis satisfied required water quality for wastewater reclamation, also stable permeation fluxes by intermittent backwashing using ozonated water. Treatment performance of the system with microfiltration and electrodialysis was investigated. Exrperimental results are summarized as follows: Metal membrane with 0.1 mm of nominal pore size showed an effluent free of suspended solids. Fouling reduction by ozonated water showed more effective than that of air backwashing. In electrodialysis, conductivity decreased rapidly as the initial voltage increased up to 10 (V). Desalination effciency with high flow rate was greater than that in low flow rate. The removal + 3– ratio of NH4 -N and PO4 -P concentration was attained to 96 and 94%, respectively, within 30 min operation of electrodialysis. In a long-term operation of the system, the average removal ratio + 3– of NH4 -N and PO4 -P concentration showed over 94 and 90%, respectively. Suggested wastewater reclamation system showed stable water qualities during operational period over 6 months. Therefore, it is expected to be an applicable and useful system for the reclamation of wastewater.