Recovery of clindamycin from fermentation wastewater with nanofiltration membranes

Experiments were carried out on clindamycinʹs separation and recovery from clindamycin fermentation wastewater with nanofiltration (NF) membranes. Four types of flat-sheet NF membranes, DLNF-1, NTR-7250, XCNF-1 and MPF-44, were tested under different dynamic operating conditions. It was found that the operating pressure and solute concentration had great influence on membrane performance while flow rates (or velocities) had little influence on membrane performance. Experiments on SO42- rejection were conducted with such four flat-sheet NF membranes because SO42- had bad influence on microbes in biochemical process following the NF process. The results indicated that DLNF-1 and MPF-44 membranes had higher SO42- rejection among four membranes. Two spiral membranes, MPS-44 (1.4 m^2) and DLNF2-30 (0.24 m^2), were adopted in a concentrating process for clindamycinʹs separation and recovery from clindamycin fermentation wastewater under laboratory conditions. After being operated for 60 h, clindamycin wastewater was concentrated from 266 to 26 L, and the clindamycin was concentrated from 220 to 1940 mg/L, which met the demand of reuse. This research may widen the application of NF membranes in disposal of pharmaceutical wastewater.