Comparison of the Performance of Membranes in Treatment from Industry Tannery Wastewaters

ESTELA ROMERO DÓNDIZ; JORGE E. ALMAZÁN; VERÓNICA B. RAJAL; ELZA CASTRO VIDAURRE

Río de Janeiro

Simposio; II Simposio de Processos de Separacao com Membranas; 2013

The leather tanning industry consumes large amounts of water and produces, consequently, significant volumes of wastewater with high concentration of chemicals and organic matter. One of the main chemicals present in effluents is the vegetable tannin, which causes a severe environmental impact [1]. A possible alternative to solve this problem is the implementation of membrane technology. In recent years, processes with membranes have been increasingly used in several industrial applications and in wastewater treatment [2-4]. Commercial polymeric membranes were used, an ultrafiltration (UF) membrane OT050 (Pall Life Sciences) with a transmembrane pressure (TMP) of 5 bar and two nanofiltration (NF) membranes: MPF-36 (Koch Membrane) and DL (GE Osmonics) with a TMP of 15 bar. The morphological characterization of the membranes was performed: contact angle, thickness, porosity and scanning electron microscopy (SEM). An equipment crossflow filtration was used to test the membranes. This equipment had a stainless steel flat cell and an effective membrane area of 0.004 m2. All tests were performed with an effluent coming from the vegetable tanning step from the tanning industry. The results indicate that all membranes have a similar average of permeate flux, showing that the MPF-36 membrane has the highest flow (18.10 ± 6.10 L/m2h). Regarding observed rejection of tannins, OT50 and MPF-36 membranes have similar rejections (74% and 78% respectively), while DL membrane presented an excellent rejection of 98%. The three membranes can be feasibly to use in the treatment of wastewater from the leather industry. [1] A. Cassano, J. Adzet, R. Molinari, M.G. Buonomenna, J. Roig, E. Drioli (2003), Membrane treatment by nanofiltration of exhausted vegetable tannin liquors from the leather industry, Water Res., 37, 2426-2434. [2] C. Conidi, A. Cassano, E. Drioli, A membrane-based study for the recovery of polyphenols from bergamot juice (2011), J. Membrane Sci., 375, 182-190. [3] H.A. Mousa, Investigation of UF membranes fouling by humic acid (2007), Desalination, 217, 38-51. [4] C.J. Huang, B.M. Yang, K.S. Chen, C.C. Chang, C.M. Kao (2011), Application of membrane technology on semiconductor wastewater reclamation: A pilot-scale study, Desalination, 278, 203-210.