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The selection of a suitable draw solution (DS) is critically important for the forward osmosis (FO)-based processes since membrane fouling and inhibition caused by DS are the key problems in anaerobic osmotic membrane bioreactor (AnOMBR) systems. This study aims to select a suitable DS for the AnOMBR system treating slaughterhouse wastewater, considering the results of FO performance and the biochemical methane potential (BMP) test. In the first step of the study, the DSs obtained from the literature review were subjected to prescreening, and 18 DSs were evaluated. Eight out of 18 DSs (4 organics and 4 inorganics) were selected using the first analytical hierarchical process (AHP). In the second stage, reverse salt flux selectivity (RSFS), water flux (Jw), and reverse salt flux (Js) values were determined to evaluate the FO performance of the 8 selected DSs by batch FO experiments. A BMP test was performed to investigate the inhibition effect of each DS on the anaerobic performance. The experimental results of batch FO and BMP studies were subjected to a second AHP analysis. The second AHP analysis showed that MgCl2was the most suitable DS. The autopsy analysis demonstrated that the primary source of fouling on the FO membrane was the accumulation of MgCl2on the membrane’s surface. Although the fouling on the FO membrane did not seriously damage the membrane structure, it caused the membrane surface to become rougher and more hydrophobic.

Less costly to AnMBR, anaerobic osmotic membrane bioreactor (AnOMBR) proceeds water and energy−efficient progresses within green and cleaner technologies. Long−term effectively operation of AnOMBR in high salinities due to salt accumulation is of the greatest priority, accompanied with a cost−performance efficient and non−inhibitory draw solution (DS) usage. Operational stability of AnOMBR in industrial wastewater treatment was studied at 30 mS/cm using the most favorable organic and inorganic DS within 29 DSs in our prior work, namely HCOONa and CaCl2. Osmotic and microbial yields during unintervented operations were lost due to severe salt stress and membrane biofouling. With a virgin membrane replacement, removal efficiencies, water and salt flux selectivity were partially restored, but the AnOMBRs turned towards collapse due to microbial activity lost. Therefore, sludge inoculation was applied and improved all AnOMBR performances to levels so close to before losses with 78 ± 3 % COD and 98.3 ± 0.6 % PO43-–P, 0.44 ± 0.2 L CH4/d excluding NH4+–N of 44 ± 10 %. It was designated that reverse salt passage for both the DS was responsible for approximately two-thirds of in-reactor salt build-up during stable AnOMBR operations. Statistical analysis results of the AnOMBR system for HCOONa and CaCl2showed that statistical significances of performances in treatments with both DSs were from moderate to strong evidence levels. Microbial diversity increased by salt accumulation, and archaeal community differentiated. HCOONa promoted hydrogenotrophic halotolerant methanogenic archaeas, but not by CaCl2. Biofilm formed predominantly by biomass, Na+/Ca2+−bound biopolimers and inorganic precipitates provided bioactively better C, N, and P exhaustions in more porous and thicker secondary membrane layer by HCOONa. Beyond a virgin membrane replacement and sludge inoculation, an AnOMBR can be efficiently operated by sludge acclimation to high salinities, finest membrane clean-up, and even fabrication of FO membrane with the integrated nano-structured novel membranes such as including silver, nanofibers, graphene oxides etc.

The study presented focuses on treatment and recycling facilities of highly polluted water-based paint wastewater from electronics industry, using coagulation-flocculation, Fenton’s oxidation and membrane processes. The treated water is sought after for recycling purposes within the painting unit and the water quality is negligible except suspended solids. The wastewater used in this study was characterized as highly polluted wastewater with high concentrations of COD (55,000–144,000 mg/l) and SS (9500–32,000 mg/l), alkaline and blackish colored. Coagulation-flocculation using alum and FeSO4was investigated. 67% of COD removal was achieved at 1000 mg/l of alum dosage whereas coagulation with FeSO4obtained 45% removal efficiency at 750 mg/l dosage. The Fenton’s oxidation process gave good results for the removals of COD and color. 81% of COD removal was achieved at a molar ratio of [H2O2]/[Fe+2] = 10 with 2 m H2O2. Waste sludge produced during the Fenton’s process was less than that of coagulation, but still required hazardous chemical sludge disposal. This study showed that the total flux decline for the FM UP005 ultrafiltration membrane was 73% and the flux decline due to membrane fouling was 9%. The use of membrane filtration causes no sludge disposal problems since the concentrate can be recycled or reused. Cost analysis involving investment, operation and maintenance, and waste sludge disposal should be made to decide the treatment and/or recycling process.

The study presented focuses on treatment and recycling facilities of highly polluted water-based paint wastewater from electronics industry, using coagulation-flocculation, Fenton’s oxidation and membrane processes. The treated water is sought after for recycling purposes within the painting unit and the water quality is negligible except suspended solids. The wastewater used in this study was characterized as highly polluted wastewater with high concentrations of COD (55,000–144,000 mg/l) and SS (9500–32,000 mg/l), alkaline and blackish colored. Coagulation-flocculation using alum and FeSO4was investigated. 67% of COD removal was achieved at 1000 mg/l of alum dosage whereas coagulation with FeSO4obtained 45% removal efficiency at 750 mg/l dosage. The Fenton’s oxidation process gave good results for the removals of COD and color. 81% of COD removal was achieved at a molar ratio of [H2O2]/[Fe+2] = 10 with 2 m H2O2. Waste sludge produced during the Fenton’s process was less than that of coagulation, but still required hazardous chemical sludge disposal. This study showed that the total flux decline for the FM UP005 ultrafiltration membrane was 73% and the flux decline due to membrane fouling was 9%. The use of membrane filtration causes no sludge disposal problems since the concentrate can be recycled or reused. Cost analysis involving investment, operation and maintenance, and waste sludge disposal should be made to decide the treatment and/or recycling process.