5. Integration of MBRs with other technologies

Membrane bioreactors (MBRs) have recently emerged with integrated MBR systems, along with other treatment technologies. The purposes of the integrated MBR are to improve qualities of permeates, mitigate membrane fouling, and enhance the stability of the treatment process. Recent studies have provided improvements in the degradation of micropollutants using integrated

processes. There are several methods to reduce the membrane fouling of MBR such as optimization of HRT and SRT which were discussed in some review papers. These processes containing biofilm carriers, suspended/attached growth system, or cross-linked enzyme aggregates showed

Efficient Removal Approach of Micropollutants in Wastewater Using Membrane Bioreactor

http://dx.doi.org/10.5772/intechopen.75183

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The advantages and disadvantages of various integrated systems, such as advanced oxidation processes (AOPs) [79], reverse osmosis (RO-MBRs) [64], forward osmosis (FO-MBRs) [80], membrane distillation (MDBRs) [81], microbial fuel cells (MBR-MFCs) [7], anaerobic (AnMBRs) [82], biofilm (BF-MBR) [83], and granular (GMBR) membrane bioreactors [84] to demonstrate their ability to reduce membrane contamination, are given in the Table 5. Combined MBR process configurations and conventional biological therapies, as an alternative, resulted in more consistent results. As shown in the studies, the removal efficiency of each of the micropollutants is different for the different membrane technologies. The value ranges from close to zero to almost complete removal. For example, the removal efficiency of carbamazepine is less than 20% with ASP and MBR and up to 93% with MBR-NF and higher than 99% with MBR-RO, MBR-PAC, and MBR-GAC [52]. The use of combinations of different complementary technologies has produced promising results. Nonetheless, there is a lack of a holistic understanding of the nature of pollutants, their interactions, and some predictable relationships between the best available specific technologies. More practice is needed to

better removal of micropollutants, even on recalcitrant compounds such as CBZ [78].

evaluate the hybrid MBR systems proposed in the treatment of micropollutants [48].

In recent years, pharmaceutical products have been a cause for concern due to the persistence of their presence in aquatic environments. Drugs are known to be involved in a variety of aquatic environments, including domestic wastewater, hospital discharges, sewage treatment

Pharmaceutical products can preserve their original concentrations and structures, or they can be mobilized for life in water matrices and converted to other active (or inactive) compounds. The presence of micropollutants in aqueous environments is an increasing concern due to their potentially harmful effects on aquatic life. Since this situation poses a serious danger to the

As it is clear from this work, today's CAS is not sufficient for the destruction of many pharmaceutical substances in the wastewater of the AAT. For these pollutants, the use of MBR systems developed by adding membranes to CAS systems has begun to be used, and these are often more effective at removing pollutant concentrations than traditional biological treatment systems. MBR technology has become a reliable and valuable option with many advantages. However, in addition to its advantages, membrane fouling is a major obstacle to the development of these systems. To this end, it will be useful to focus on the reduction of energy demand and membrane contamination during operation, along with the development of integrated MBR systems, with future research. Further work is needed to assess which system actually makes more cost–benefit and to investigate the toxicity of micropollutants

environment, the treatment of these pollutants is very important.

and the effect of working conditions after processing.

6. Conclusions

plants, and water treatment plants.


Table 5. Advantages and disadvantages of various integrated MBRs in wastewater treatment technology [55].

processes. There are several methods to reduce the membrane fouling of MBR such as optimization of HRT and SRT which were discussed in some review papers. These processes containing biofilm carriers, suspended/attached growth system, or cross-linked enzyme aggregates showed better removal of micropollutants, even on recalcitrant compounds such as CBZ [78].

The advantages and disadvantages of various integrated systems, such as advanced oxidation processes (AOPs) [79], reverse osmosis (RO-MBRs) [64], forward osmosis (FO-MBRs) [80], membrane distillation (MDBRs) [81], microbial fuel cells (MBR-MFCs) [7], anaerobic (AnMBRs) [82], biofilm (BF-MBR) [83], and granular (GMBR) membrane bioreactors [84] to demonstrate their ability to reduce membrane contamination, are given in the Table 5. Combined MBR process configurations and conventional biological therapies, as an alternative, resulted in more consistent results. As shown in the studies, the removal efficiency of each of the micropollutants is different for the different membrane technologies. The value ranges from close to zero to almost complete removal. For example, the removal efficiency of carbamazepine is less than 20% with ASP and MBR and up to 93% with MBR-NF and higher than 99% with MBR-RO, MBR-PAC, and MBR-GAC [52]. The use of combinations of different complementary technologies has produced promising results. Nonetheless, there is a lack of a holistic understanding of the nature of pollutants, their interactions, and some predictable relationships between the best available specific technologies. More practice is needed to evaluate the hybrid MBR systems proposed in the treatment of micropollutants [48].
