摘要

Digital textile printing (DTP) is considered as an environmentally benign process because its wastewater production is relatively small compared with the conventional textile printing system. DTP is usually practiced at building office in an urban area rather than in a textile industrial complex, so that process development for on-site treatment of the DTP wastewater is currently needed. The aim of this study was to propose a DTP wastewater treatment system suitable for operation in building and to verify if the proposed system has a rationale. A treatment system should be compact and reliable because it should be installed near the DTP system. Thus, a hybrid system consisting of ozone, ultrafiltration (UF) and reverse osmosis (RO) was proposed for treatment of DTP wastewater. Prior to UF and RO, ozone was introduced to the DTP wastewater to reduce organic loadings to membrane filtration as well as to treat the concentrates recycled from UF and RO When ozone was injected with C.T value of 255 g.s/L, the removal efficiency of COD and color was 63 and 81%, respectively. Ozonation of the DTP wastewater led to aggregation of colloidal particles, so that the cake resistance (R(c)) calculated after ozone and UF was lower than that of the control (= without ozonation), suggesting that pre-ozonation is beneficial to not only flux enhancement but also to good permeate water quality. Further treatment of UF permeates using RO was carried out since the UF permeates was not enough for direct discharge or reuse. Final effluents through the whole process of ozonation, UF and RO met the criteria of direct discharge and reuse, suggesting that the proposed hybrid system could be used for DTP wastewater treatment satisfactorily.

  • 出版日期2009-1-15