Batik effluent reclamation through a task-orientated coupling process of nanofiltration membranes

AbstractBatik industries generate large amounts of effluents with high chromaticity, chemical oxygen demand (COD), turbidity, and salinity. The present study aims to recycle batik effluent using nanofiltration (NF) membranes. The effects of various operating conditions on the performances of three NF membranes (NF6, NF2A, and NF3A) were examined in terms of the removal rate of salt, COD, and chromaticity, together with permeate flux. Membrane fouling and cleaning strategies were also investigated. Results showed that the NF3A membrane outperformed the other membranes under the following optimal operating conditions: operating pressure, 1 MPa; operating temperature, 20°C; and cross-flow velocity, 5 m/s. A pilot-scale test was conducted by screening a NF membrane combination, including one NF membrane with high permeate fluxes and a poor water quality and another NF membrane placed on the opposite side, to satisfy reuse requirements and to reduce investment costs. Compared with NF3A membranes alone, the com...