Comparison of Membrane Module Performance in Flat-sheet Membrane Bioreactor for Treating Spiramycin Wastewater

The performance of two flat-sheet membrane modules in a submerged membrane bioreactor(MBR)for spiramycin wastewater treatment was compared through a 120 d experiment.During 0-80 d,both the flux and specific flux of the membraneⅡ(MemⅡ) were higher than those of the membraneⅠ(MemⅠ),but the reverse was true during 81-120 d due to the irreversible fouling of MemⅡ.The average removal rates of COD,protein and carbohydrate by MemⅠwere 30.50%,14.03% and 39.51% respectively,and by MemⅡ were 29.81%,11.12% and 37.36% respectively.There was no significant difference between MemⅠ and MemⅡ(p=0.05) on removal of organic matters.The apparent molecular weight(AMW) distribution and turbidity of the two membranes permeates did not show a significant difference either.Composition analysis of the membrane chemical cleaning solutions indicated that these two membranes were mainly fouled by organic components.Based on the techno-economic analysis,MemⅠ is more suitable for treating spiramycin wastewater.