Applicability of an integrated moving sponge biocarrier-osmotic membrane bioreactor MD system for saline wastewater treatment using highly salt-tolerant microorganisms

Abstract

Osmotic membrane bioreactors (OsMBRs) are a recent breakthrough technology designed to treat wastewater. Nevertheless, their application in high-salinity wastewater treatment is not widespread because of the effects of saline conditions on microbial community activity. In response, this study developed an integrated sponge biocarrier-OsMBR system using highly salttolerant microorganisms for treating saline wastewater. Results showed that the sponge biocarrier-OsMBR obtained an average water flux of 2 L/m 2 h during a 92-day operation when 1 M MgCl 2 was used as the draw solution. The efficiency in removing dissolved organic compounds from the proposed system was more than 99%, and nutrient rejection was close to 100%, indicating excellent performance in simultaneous nitrification and denitrification processes in the biofilm layer on the carriers. Moreover, salt-tolerant microorganisms in the sponge biocarrier-OsMBR system worked efficiently in salt concentrations of 2.4%. A polytetrafluoroethylene MD membrane (pores = 0.45 μm) served to regenerate the diluted draw solution in the closed-loop system and produce high-quality water. The moving sponge biocarrier-OsMBR/MD hybrid system demonstrated its potential to treat salinity wastewater treatment, with 100% nutrient removal and 99.9% conductivity rejection.

Mesophilic microfiltration–anaerobic osmotic membrane bioreactor–membrane distillation hybrid system for phosphorus recovery

“…The FO module was vertically immersed in the bioreactor tank with the active layer of the membrane facing the feed solution. The bioreactor continuously used a magnetic stirrer to mix the solution of bioreactor and to generate sufficient force for reducing membrane fouling . Furthermore, the bioreactor was operated using synthetic wastewater supplied from a feed tank placed on a digital scale (BW12KH, Shimadzu, Japan).…”

“…The bioreactor continuously used a magnetic stirrer to mix the solution of bioreactor and to generate sufficient force for reducing membrane fouling. 26,27 Furthermore, the bioreactor was operated using synthetic wastewater supplied from a feed tank placed on a digital scale (BW12KH, Shimadzu, Japan). The synthetic wastewater was prepared using 3.64 g L −1 C 6 H 12 O 6 ·H 2 O, 0.191 g L −1 NH 4 Cl and 0.088 g L −1 KH 2 PO 4 with COD of 3500 mg L −1 , NH 4 + of 64 mg L −1 and PO 4 3− of 61 mg L −1 to provide sufficient carbon, nitrogen and P sources.…”

Membrane processes

“…In another study, the OMBR‐MD system utilized fixed‐film bio‐carrier to support salt‐tolerant microorganisms to treat high salinity wastewater (Nguyen et al., 2018). The system treated wastewater with 2.4% salinity and removed 100% of nutrients and 99% of salinity.…”

Analysis of the biodegradation performance and biofouling in a halophilic MBBR-MBR to improve the treatment of disinfected saline wastewater

“…The typical bioreactors for MBR integration include MBBR (moving bed biofilm reactors), BCOR (biological contact oxidation reactor), UASB (up-flow anaerobic sludge blanket), SBR (sequencing batch reactor), MFC (microbial fuel cells), chemostat and bio-carriers. Since MBBR has unique advantages of fast start-up, large biomass, direct dosing and space saving, MBBR-MBR has been used in this work for saline wastewater treatment, where the key strategy involves the integration of another bioreactor and the use of highly salt-tolerant microorganisms ( Nguyen et al., 2018 ). The NaClO-containing wastewater, as introduced above, is an emerging wastewater from disinfection against the coronaviruses.…”