Synthesis of smart hydrogel polymers as a new draw solution in an OMBR (Osmotic Membrane Bioreactor)

Because of water scarcity, water and wastewater treatment technologies become more important. Recently, the novel osmotic membrane bioreactor has been gained a significant attention. OMBR is a membrane bioreactor which has a forward osmosis membrane rather than MF and UF membranes that are used in the convectional membrane bioreactors. This process can be used as an auxiliary unit after MBR or as a standalone unit for the biological treatment. Comparing with the conventional MBR, this type of bioreactor has very attractive properties such as high pollutants selectivity (organic and inorganic), low energy consumption and, more importantly, low membrane fouling.One of the main challenges in OMBR is selecting a suitable draw agent which can induce a desired driving force. Different chemical solutions, such as NaCl, MgCl2, MNPs, sugars, polyelectrolytes, etc., have been introduced as the draw agents. However the use of hydrogels and smart polymers in OMBR has not been reported yet.In this work, hydrogel particles were synthesized using the radical polymerization. A variety of techniques such as SEM, FTIR, VSM, swelling ratio measurement were used to characterization the synthesized draw agents. Afterward a batch OMBR was conducted to evaluate the performance of the hydrogel polymers (SRT:14 days, HRT: 8hr). A continuous OMBR system was also studied using the hydrogel polymers as draw agent. The performance of the OMBR systems were investigated by measuring COD, BOD, MLSS, DO, conductivity and pure water flux permeation (LMH). The results approved that the introduced draw agent in this study has a great potential to be used in wastewater treatment processes.

کلیدواژه ها:

Draw solution ، FO membrane ، Hydrogel polymers ، OMBR ، Wastewater treatment