Análise do comportamento hidrodinâmico de um módulo de membranas de ultrafiltração aplicado ao tratamento de efluentes em meio anaeróbio

Abstract

Anaerobic membrane bioreactors (AnMBR) have been evolving as a promising technology for wastewater treatment compared to conventional anaerobic treatment systems and even membranes associated with aerobic bioreactors (MBR). Although the technology is well established, anaerobic membrane bioreactors processes run up against challenges inherent in all membrane processes, which are flow restriction pheno mena. It is essential for the bioreactor’s operational autonomy for the optimization of biogas production that the membranes are not a limiting factor to the process. In this scenario, this work was developed to obtain and analyze experimental data of hollow fiber polymeric ultrafiltration membranes filtrating an anaerobic effluent. Experimental data refers to permeate fluxes (JP) and the corresponding resistances to filtration (R), for TSS concentrations of 0.806, 5.0, 10.0, 20.0 and 40.0 40,0 g∙L-1 and constant transmembrane pressures (TMP) of 140, 260 and 380 mbar. The main results show that, for the same concentration, TMP of 140 mbar reached permeate volumes very close to the highest TMP, with less energy demand for pumping equipment. In general, from the time 40 min, the regularization of JP occurs in average values ranging from 3.0 0 L∙m- ²∙h-1 for the highest TSS concentration and 6.0 0 L∙m- ²∙h-1 for the others. However, the average values of JP do not decrease as TSS concentration increases, suggesting the interference of another factors in the filtration process, such as particle size distribution. Different from JP, total resistance (RT) increased throughout the tests, with maximum values between 1,9∙1013 m-1 for the lowest TSS concentration and 3,5∙1013 m-1 for the highest one, at 240 min, suggesting the existence of a relation between TSS concentration and RT. The results have shown that the membrane application is not a limiting technology to these reactors, since they can operate even with significant increases in drag of solids.