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A side-stream cross-flow anaerobic self-forming dynamic membrane bioreactor (AnSFDMBR) connected with an up-flow anaerobic sludge blanket (UASB) reactor was used to replace the UASB and middle settling tank in sulfate reduction, autotrophic denitrification, and nitrification integrated (SANI) process. To reduce the water and energy consumption for AnSFDMBR backwashing, the optimum condition of trans-membrane pressure (TMP)-based backwashing were investigated under sequential batch operations. Based on the optimum condition, a lab-scale AnSFDMBR was operated continuously for 243 days without a drop in flux, with good effluent quality. In the sequential batch operation study, AnSFDMBR showed no significant accumulation of total extracellular polymeric substances (EPSs) during 40 days of operation without backwashing. Polysaccharides slightly accumulated in the dynamic layer regardless of the final TMP and operation duration, indicating that TMP-based backwashing is suitable for the studied AnSFDMBR system. In long-term operation with TMP-based backwashing, total EPSs in dynamic layer to sludge ratio dramatically dropped during the fouling phase. According to the evaluation of total organic sulfur (TOS) in dynamic layer and mesh EPSs, it was found that TOS, mainly poly-sulfur generated in UASB reactor, played a critical role in fouling in saline wastewater treatment. TOS deposited on the mesh over 40% by weight of the total EPS in the fouling phase clearly led to system fouling. Additional sequential batch operations with different seawater percentages (%V/V) (control, 10%, 20%, 30% and 50%) demonstrated that the TOS accumulation on the mesh increased with time and salinity which also aligned with the long-term operation. © 2023 Elsevier B.V.

In the current study, MFCs treating saline wastewater with the different conductivities of 5.0 ± 0.2, 7.7 ± 0.6, 10.5 ± 0.9, 13.0 ± 1.0, 15.3 ± 1.0, and 16.0 ± 0.1 mS/cm were investigated. Increasing salinity drives a considerable shift of microbial communities, and it also affects metabolic pathways in MFCs. Overwhelming acetate oxidizing electron transfer with moderate conductivities between 7.7 and 13.0 mS/cm led to high energy outputs. Power generation at the low conductivities of less than 7.7 mS/cm was restricted by the competition between fermentative bacteria (e.g., Lactobacillus) and exoelectrogens (e.g., Pseudomonas and Shewanella) for substrate utilization. Increasing salinity beyond 13 mS/cm suppressed the fermentation of glucose to butyrate. It also induced sulfidogenesis; sulfide oxidizing bacteria Desulfovibrio (5.2%), Desulfuromonas (3.7%) and exoelectrogen Pseudomonas (1.1%) formed a sulfur-driven current production, thereby resulting in low energy outputs. The present study revealed the effects of ionic conductivity on electrical energy production and provided insights into the dynamics of the MFCs substrate utilization. © 2021 Elsevier B.V.

In the current study, MFCs treating saline wastewater with the different conductivities of 5.0 ± 0.2, 7.7 ± 0.6, 10.5 ± 0.9, 13.0 ± 1.0, 15.3 ± 1.0, and 16.0 ± 0.1 mS/cm were investigated. Increasing salinity drives a considerable shift of microbial communities, and it also affects metabolic pathways in MFCs. Overwhelming acetate oxidizing electron transfer with moderate conductivities between 7.7 and 13.0 mS/cm led to high energy outputs. Power generation at the low conductivities of less than 7.7 mS/cm was restricted by the competition between fermentative bacteria (e.g., Lactobacillus) and exoelectrogens (e.g., Pseudomonas and Shewanella) for substrate utilization. Increasing salinity beyond 13 mS/cm suppressed the fermentation of glucose to butyrate. It also induced sulfidogenesis; sulfide oxidizing bacteria Desulfovibrio (5.2%), Desulfuromonas (3.7%) and exoelectrogen Pseudomonas (1.1%) formed a sulfur-driven current production, thereby resulting in low energy outputs. The present study revealed the effects of ionic conductivity on electrical energy production and provided insights into the dynamics of the MFCs substrate utilization. © 2021 Elsevier B.V.

In the current study, MFCs treating saline wastewater with the different conductivities of 5.0 ± 0.2, 7.7 ± 0.6, 10.5 ± 0.9, 13.0 ± 1.0, 15.3 ± 1.0, and 16.0 ± 0.1 mS/cm were investigated. Increasing salinity drives a considerable shift of microbial communities, and it also affects metabolic pathways in MFCs. Overwhelming acetate oxidizing electron transfer with moderate conductivities between 7.7 and 13.0 mS/cm led to high energy outputs. Power generation at the low conductivities of less than 7.7 mS/cm was restricted by the competition between fermentative bacteria (e.g., Lactobacillus) and exoelectrogens (e.g., Pseudomonas and Shewanella) for substrate utilization. Increasing salinity beyond 13 mS/cm suppressed the fermentation of glucose to butyrate. It also induced sulfidogenesis; sulfide oxidizing bacteria Desulfovibrio (5.2%), Desulfuromonas (3.7%) and exoelectrogen Pseudomonas (1.1%) formed a sulfur-driven current production, thereby resulting in low energy outputs. The present study revealed the effects of ionic conductivity on electrical energy production and provided insights into the dynamics of the MFCs substrate utilization. © 2021 Elsevier B.V.

Enhanced pollutants removal from saline wastewater was investigated in simultaneous anammox and denitrification (SAD) process with glycine betaine (GB) addition. Long-term operation indicated the optimal GB dose was around 0.4 mM, which enhanced both anammox and denitrifying activity by 30% and 45%, respectively. The total nitrogen and organic removal rates were 0.38 ± 0.2 kgN/m3/d and 0.34 ± 0.3 kgCOD/m3/d, respectively, which increased by 34.5% and 20.5%. Independent of GB dose, denitrifying activity was promoted, but anammox activity was drastically deteriorated after excessive GB addition. The optimal GB dose predicated by both Gaussian and Modified-Boltzmann models were 0.42–0.45 mM. Besides, the bacterial activity recovery after excessive GB addition could be analyzed by the Modified-Boltzmann model. With 1.5 mM GB, granular floatation occurred since numerous gas bubbles were inside the granules. In general, exogenous GB addition can mitigate salinity inhibition and promote pollutants removal from saline wastewater. © 2020 Elsevier Ltd

Enhanced pollutants removal from saline wastewater was investigated in simultaneous anammox and denitrification (SAD) process with glycine betaine (GB) addition. Long-term operation indicated the optimal GB dose was around 0.4 mM, which enhanced both anammox and denitrifying activity by 30% and 45%, respectively. The total nitrogen and organic removal rates were 0.38 ± 0.2 kgN/m3/d and 0.34 ± 0.3 kgCOD/m3/d, respectively, which increased by 34.5% and 20.5%. Independent of GB dose, denitrifying activity was promoted, but anammox activity was drastically deteriorated after excessive GB addition. The optimal GB dose predicated by both Gaussian and Modified-Boltzmann models were 0.42–0.45 mM. Besides, the bacterial activity recovery after excessive GB addition could be analyzed by the Modified-Boltzmann model. With 1.5 mM GB, granular floatation occurred since numerous gas bubbles were inside the granules. In general, exogenous GB addition can mitigate salinity inhibition and promote pollutants removal from saline wastewater. © 2020 Elsevier Ltd

Enhanced pollutants removal from saline wastewater was investigated in simultaneous anammox and denitrification (SAD) process with glycine betaine (GB) addition. Long-term operation indicated the optimal GB dose was around 0.4 mM, which enhanced both anammox and denitrifying activity by 30% and 45%, respectively. The total nitrogen and organic removal rates were 0.38 ± 0.2 kgN/m3/d and 0.34 ± 0.3 kgCOD/m3/d, respectively, which increased by 34.5% and 20.5%. Independent of GB dose, denitrifying activity was promoted, but anammox activity was drastically deteriorated after excessive GB addition. The optimal GB dose predicated by both Gaussian and Modified-Boltzmann models were 0.42–0.45 mM. Besides, the bacterial activity recovery after excessive GB addition could be analyzed by the Modified-Boltzmann model. With 1.5 mM GB, granular floatation occurred since numerous gas bubbles were inside the granules. In general, exogenous GB addition can mitigate salinity inhibition and promote pollutants removal from saline wastewater. © 2020 Elsevier Ltd

This study investigated the polyphosphates accumulation rate in a novel sulfur transformation-centric enhanced biological phosphorus removal (SEBPR) process. The SEBPR system was continuously operated over 120 days in a sequencing batch reactor (SBR) that alternated between the anaerobic mode and the anoxic mode of operation (temperature: 30 °C and salinity: 6000 mg/L Cl−). In addition to the SBR, batch experiments were carried out to test the effect of two different sulfate concentrations on the system performance and sulfur-phosphorus transformations. The key intercellular polymers of polyphosphates and polysulfur (poly-S) were identified by employing advanced microscopes. Metagenomic analysis was performed to characterize the diversity of microbes and their functions enriched in the SEBPR system. Finally, several molecular techniques including flow cytometry cell sorting and 16S DNA high-throughput sequencing were applied to identify the phosphorus-accumulating organisms (PAOs). The amounts of P release and P uptake in the SEBPR increased gradually to nearly 18 ± 6.4 mg P/L and 26.5 ± 6.7 mg P/L respectively, yielding a net P removal efficiency of 84 ± 25%. Batch tests indicated no polyhydroxyalkanate (PHA) synthesis, but P uptake was observed and it was correlated with the intracellular poly-S consumption, suggesting that the poly-S could act as an intracellular energy source for P uptake and polyphosphates formation. Moreover, CLSM and TEM micrographs clearly showed the presence of intercellular polyphosphates and poly-S respectively. Metagenomic analysis revealed that Proteobacteria (36.5%), Bacteroidetes (23.3%), Thermotogae (7.1%), Chloroflexi (4.5%) and Firmicutes (2.3%) were the dominant phyla in Bacteria. The conventional PAO of Candidatus Accumulibacter was found at a low abundance of 0.32% only; and an uncultured genus close to Rhodobacteraceae at the family level is speculated to be the putative sulfur PAO (SPAO). Finally, this research suggests that p

This study investigated the polyphosphates accumulation rate in a novel sulfur transformation-centric enhanced biological phosphorus removal (SEBPR) process. The SEBPR system was continuously operated over 120 days in a sequencing batch reactor (SBR) that alternated between the anaerobic mode and the anoxic mode of operation (temperature: 30 °C and salinity: 6000 mg/L Cl−). In addition to the SBR, batch experiments were carried out to test the effect of two different sulfate concentrations on the system performance and sulfur-phosphorus transformations. The key intercellular polymers of polyphosphates and polysulfur (poly-S) were identified by employing advanced microscopes. Metagenomic analysis was performed to characterize the diversity of microbes and their functions enriched in the SEBPR system. Finally, several molecular techniques including flow cytometry cell sorting and 16S DNA high-throughput sequencing were applied to identify the phosphorus-accumulating organisms (PAOs). The amounts of P release and P uptake in the SEBPR increased gradually to nearly 18 ± 6.4 mg P/L and 26.5 ± 6.7 mg P/L respectively, yielding a net P removal efficiency of 84 ± 25%. Batch tests indicated no polyhydroxyalkanate (PHA) synthesis, but P uptake was observed and it was correlated with the intracellular poly-S consumption, suggesting that the poly-S could act as an intracellular energy source for P uptake and polyphosphates formation. Moreover, CLSM and TEM micrographs clearly showed the presence of intercellular polyphosphates and poly-S respectively. Metagenomic analysis revealed that Proteobacteria (36.5%), Bacteroidetes (23.3%), Thermotogae (7.1%), Chloroflexi (4.5%) and Firmicutes (2.3%) were the dominant phyla in Bacteria. The conventional PAO of Candidatus Accumulibacter was found at a low abundance of 0.32% only; and an uncultured genus close to Rhodobacteraceae at the family level is speculated to be the putative sulfur PAO (SPAO). Finally, this research suggests that p

This study investigated the polyphosphates accumulation rate in a novel sulfur transformation-centric enhanced biological phosphorus removal (SEBPR) process. The SEBPR system was continuously operated over 120 days in a sequencing batch reactor (SBR) that alternated between the anaerobic mode and the anoxic mode of operation (temperature: 30 °C and salinity: 6000 mg/L Cl−). In addition to the SBR, batch experiments were carried out to test the effect of two different sulfate concentrations on the system performance and sulfur-phosphorus transformations. The key intercellular polymers of polyphosphates and polysulfur (poly-S) were identified by employing advanced microscopes. Metagenomic analysis was performed to characterize the diversity of microbes and their functions enriched in the SEBPR system. Finally, several molecular techniques including flow cytometry cell sorting and 16S DNA high-throughput sequencing were applied to identify the phosphorus-accumulating organisms (PAOs). The amounts of P release and P uptake in the SEBPR increased gradually to nearly 18 ± 6.4 mg P/L and 26.5 ± 6.7 mg P/L respectively, yielding a net P removal efficiency of 84 ± 25%. Batch tests indicated no polyhydroxyalkanate (PHA) synthesis, but P uptake was observed and it was correlated with the intracellular poly-S consumption, suggesting that the poly-S could act as an intracellular energy source for P uptake and polyphosphates formation. Moreover, CLSM and TEM micrographs clearly showed the presence of intercellular polyphosphates and poly-S respectively. Metagenomic analysis revealed that Proteobacteria (36.5%), Bacteroidetes (23.3%), Thermotogae (7.1%), Chloroflexi (4.5%) and Firmicutes (2.3%) were the dominant phyla in Bacteria. The conventional PAO of Candidatus Accumulibacter was found at a low abundance of 0.32% only; and an uncultured genus close to Rhodobacteraceae at the family level is speculated to be the putative sulfur PAO (SPAO). Finally, this research suggests that p

Saline wastewater is known to affect the performance of phosphate-accumulating organisms (PAOs) in enhanced biological phosphorus removal (EBPR) process. However, studies comparing the effect of salinity on different PAO clades are lacking. In this study, 'Candidatus Accumulibacter phosphatis' Clade I and II (hereafter referred to as PAOI and PAOII) were highly enriched (~90% in relative abundance as determined by quantitative FISH) in the form of granules in two sequencing batch reactors. Anaerobic and aerobic batch experiments were conducted to evaluate the effect of salinity on the kinetics and stoichiometry of PAOI and PAOII. PAOI and PAOII communities showed different priority in using polyphosphate (poly-P) and glycogen to generate ATP in the anaerobic phase when exposed to salt, with PAOI depending more on intracellular poly-P degradation (e.g., the proportion of calculated ATP derived from poly-P increased by 5-6% at 0.256 mol/L NaCl or KCl) while PAOII on glycolysis of intracellularly stored glycogen (e.g., the proportion of calculated ATP derived from glycogen increased by 29-30% at 0.256 mol/L NaCl or KCl). In the aerobic phase, the loss of phosphate uptake capability was more pronounced in PAOII due to the higher energy cost to synthesize their larger glycogen pool compared to PAOI. For both PAOI and PAOII, aerobic conversion rates were more sensitive to salt than anaerobic conversion rates. Potassium (K+) and sodium (Na+) ions exhibited different effect regardless of the enriched PAO culture, suggesting that the composition of salt is an important factor to consider when studying the effect of salt on EBPR performance., BT/Environmental Biotechnology

Increasing amounts of saline (waste)water with high concentrations of organic pollutants are generated globally. In the anaerobic (waste)water treatment domain, high salt concentrations are repeatedly reported to inhibit methanogenic activity and strategies to overcome this toxicity are needed. Current research focuses on the use of potential osmolyte precursor compounds for osmotic stress alleviation in granular anaerobic sludges upon exposure to hypersalinity shocks. Glutamic acid, aspartic acid, lysine, potassium, gelatine, and tryptone were tested for their potential to alleviate osmotic stress in laboratory grown and full – scale granular sludge. The laboratory grown granular sludge was adapted to 5 (R5) and 20 (R20) g Na+/L. Full-scale granular sludge was obtained from internal circulation reactors treating tannery (waste)water with influent conductivity of 29.2 (Do) and 14.1 (Li) mS/cm. In batch experiments which focused on specific methanogenic activity (SMA), R5 granular sludge was exposed to a hypersalinity shock of 20 g Na+/L. The granular sludge of Do and Li was exposed to a hypersalinity shock of 10 g Na+/L with sodium acetate as the sole carbon source. The effects on R20 granular sludge were studied at the salinity level to which the sludge was already adapted, namely 20 g Na+/L. Dosing of glutamic acid, aspartic acid, gelatine, and tryptone resulted in increased SMA compared to only acetate fed batches. In batches with added glutamic acid, the SMA increased by 115% (Li), 35% (Do) and 9% (R20). With added aspartic acid, SMA increased by 72% (Li), 26% (Do), 12% (R5) and 7% (R20). The addition of tryptone resulted in SMA increases of 36% (R5), 17% (R20), 179% (Li), and 48% (Do), whereas added gelatine increased the SMA by 30% (R5), 14% (R20), 23% (Li), and 13% (Do). The addition of lysine, meanwhile, gave negative effects on SMA of all tested granular sludges. Potassium at sea water Na/K ratio (27.8 w/w) had a slight positive effect on SMA of Do (7.3%) a

Saline wastewater is known to affect the performance of phosphate-accumulating organisms (PAOs) in enhanced biological phosphorus removal (EBPR) process. However, studies comparing the effect of salinity on different PAO clades are lacking. In this study, 'Candidatus Accumulibacter phosphatis' Clade I and II (hereafter referred to as PAOI and PAOII) were highly enriched (~90% in relative abundance as determined by quantitative FISH) in the form of granules in two sequencing batch reactors. Anaerobic and aerobic batch experiments were conducted to evaluate the effect of salinity on the kinetics and stoichiometry of PAOI and PAOII. PAOI and PAOII communities showed different priority in using polyphosphate (poly-P) and glycogen to generate ATP in the anaerobic phase when exposed to salt, with PAOI depending more on intracellular poly-P degradation (e.g., the proportion of calculated ATP derived from poly-P increased by 5-6% at 0.256 mol/L NaCl or KCl) while PAOII on glycolysis of intracellularly stored glycogen (e.g., the proportion of calculated ATP derived from glycogen increased by 29-30% at 0.256 mol/L NaCl or KCl). In the aerobic phase, the loss of phosphate uptake capability was more pronounced in PAOII due to the higher energy cost to synthesize their larger glycogen pool compared to PAOI. For both PAOI and PAOII, aerobic conversion rates were more sensitive to salt than anaerobic conversion rates. Potassium (K+) and sodium (Na+) ions exhibited different effect regardless of the enriched PAO culture, suggesting that the composition of salt is an important factor to consider when studying the effect of salt on EBPR performance., BT/Environmental Biotechnology

汚水処理方法は、短い水理学的滞留時間（ＨＲＴ）で汚水に含まれる有機物質および窒素を処理するために使用され、余剰汚泥を最低に抑制し、高流束運転状態で「精密ろ過」膜モジュールを維持する。膜モジュールを有する曝気ゾーンが提供される。汚水流入水が受容され、曝気ゾーンで活性汚泥を用いて処理される。酸素超過は、曝気ゾーンへ供給される酸素の流率を制限することによって維持される。汚水流入水は、曝気ゾーンで活性汚泥と混合され、第１の混合液を形成する。第１の混合液は、２つの部分で処理される。第１の混合液の第１の部分は、膜を通してろ過され、処理水として透過液を形成する。第２の部分は、曝気ゾーンから嫌気性ゾーンへ送られ、第２の混合液を形成する。第２の混合液の等しい容量は、好気性ゾーンへ再循環される。A sewage treatment method is used in order to process the organic substance and nitrogen which are contained in sewage by short hydraulic holding time (HRT), it inhibits excess sludge to the minimum, and maintains "microfiltration" membrane module by high flux operational status. The aeration zone which has a membrane module is provided. Sewage influent is received and it is processed in an aeration zone using activated sludge. An excess of oxygen is maintained by restricting the fluxion of the oxygen supplied to an aeration zone. It is mixed with activated sludge in an aeration zone, and sewage influent forms first mixed liquor. First mixed liquor is processed in two portions. The first portion of first mixed liquor is filtered through a film, and forms permeate liquid as treated water. A second portion is sent to an anaerobic zone from an aeration zone, and forms second mixed liquor. The equal capacity of second mixed liquor is recycled to an aerobic zone.

本发明提供了一种污水处理工艺、污水处理设备以及利用膜组件和膜生物反应器的工艺。在所述污水处理工艺中，污水进水首先进入安装有“大孔径”滤膜的膜组件（503）的曝气区（502）中。在曝气池中形成活性污泥，并通过控制所述曝气区（502）的氧气输送速率以维持充足的氧气。污水进水与活性污泥混合成为第一混合液。部分第一混合液经过膜过滤后形成透过液并作为出水排出反应器外，残留部分继续作为未过滤的活性污泥悬浮于曝气区（502）中。第一混合液的第二部分则被运移至厌氧区（515）中，形成第二混合液。第二混合液将会再回流至曝气区（502）中。Provided are a wastewater treatment process, a wastewater treatment apparatus, a process using a membrane module and a membrane bioreactor. In the wastewater treatment process, a wastewater influent is supplied to an aeration zone (502) having a membrane module (503) comprising a "macrofiltration" membrane. Activated sludge is established in the aeration zone (502) and an oxygen surplus is maintained by controlling a rate of oxygen supplied to the aeration zone (502). The wastewater influent is mixed with the activated sludge to form a first mixed liquid. A portion of the first mixed liquid is filtered through the membrane to form a permeate as an effluent, and leaving the residual part as unfiltered activated sludge suspending in the aeration zone (502). A second portion of the first mixed liquid is transferred to an anaerobic zone (515) to form a second mixed liquid. The second mixed liquid is recycled to the aerobic zone (502).

Enhanced biological phosphorus removal (EBPR) is a biological process for efficient phosphate removal from wastewaters through intracellular storage of polyphosphate by polyphosphate-accumulating organisms (PAO) and subsequent removal of PAO from the system through wastage of sludge. In comparison to physical and chemical phosphorus removal processes, the biological process has several advantages such as high removal efficiency, low cost, and no chemical sludge production, but disturbances and prolonged periods of insufficient phosphate removal are still observed in conventional treatment systems and the applicability of the process for the treatment of saline waters remains unclear. In this PhD project two different aspects of the enhanced biological phosphorus removal were studied. In the first part of the research, potential existence of functional diversity among PAO clades and its influence on process performance was investigated, whereas in the second part of the study, salinity effects were assessed on the metabolism of polyphosphate-accumulating organisms (PAO) and glycogen-accumulating organisms (GAO). Functional diversity among PAO clades (Chapter 2 to 5) Although genetic diversity among PAO clades has been observed in past studies, PAO were often considered to behave functionally the same. Several recent studies suggested that PAO clades may be functionally different and that some PAO clades can perform better phosphate removal than other clades. Considering the significant role of the EBPR process in nutrient removal and recovery processes and the potential effect of PAO clades prevalence on the process performance, there was a need to investigate the potential existence of functional differences among PAO clades. The objective of this part of the study was to assess the existence of functional differences among PAO clades regarding the anaerobic metabolism in relation to their storage polymers and regarding the denitrification pathways. In Chapter 2, it, Biotechnology, Applied Sciences

Enhanced biological phosphorus removal (EBPR) is a biological process for efficient phosphate removal from wastewaters through intracellular storage of polyphosphate by polyphosphate-accumulating organisms (PAO) and subsequent removal of PAO from the system through wastage of sludge. In comparison to physical and chemical phosphorus removal processes, the biological process has several advantages such as high removal efficiency, low cost, and no chemical sludge production, but disturbances and prolonged periods of insufficient phosphate removal are still observed in conventional treatment systems and the applicability of the process for the treatment of saline waters remains unclear. In this PhD project two different aspects of the enhanced biological phosphorus removal were studied. In the first part of the research, potential existence of functional diversity among PAO clades and its influence on process performance was investigated, whereas in the second part of the study, salinity effects were assessed on the metabolism of polyphosphate-accumulating organisms (PAO) and glycogen-accumulating organisms (GAO). Functional diversity among PAO clades (Chapter 2 to 5) Although genetic diversity among PAO clades has been observed in past studies, PAO were often considered to behave functionally the same. Several recent studies suggested that PAO clades may be functionally different and that some PAO clades can perform better phosphate removal than other clades. Considering the significant role of the EBPR process in nutrient removal and recovery processes and the potential effect of PAO clades prevalence on the process performance, there was a need to investigate the potential existence of functional differences among PAO clades. The objective of this part of the study was to assess the existence of functional differences among PAO clades regarding the anaerobic metabolism in relation to their storage polymers and regarding the denitrification pathways. In Chapter 2, it, Biotechnology, Applied Sciences

Conventional membrane bioreactor (MBR) systems have increasingly been studied in recent decades. However, their applications have been limited due to their drawbacks such as low flux, membrane fouling, and high operating cost. In this study, a compact macro-filtration MBR (MfMBR) process was developed by using a large pore size membrane to mitigate the membrane fouling problem. A pilot trial of MfMBR process was set up and operated to treat 10 m 3/day of saline wastewater within 4 h. The system was operated under an average permeate flux of 13.1 m3/(m2·day) for 74 days. The average total suspended solids, total chemical oxygen demand, biological oxygen demand, total Kjeldahl nitrogen, and total nitrogen removal efficiencies achieved were 94.3, 83.1, 98.0, 93.1, and 63.3%, respectively, during steady-state operation. The confocal laser scanning microscopy image indicated that the backwash could effectively remove the bio-cake and dead bacteria. Thus, the results showed that the MfMBR process, which is essentially a primary wastewater treatment process, had the potential to yield the same high quality effluent standards as the secondary treatment process; thereby suggesting that it could be used as an option when the economic budget and/or land space is limited. © IWA Publishing 2014.

Conventional membrane bioreactor (MBR) systems have increasingly been studied in recent decades. However, their applications have been limited due to their drawbacks such as low flux, membrane fouling, and high operating cost. In this study, a compact macro-filtration MBR (MfMBR) process was developed by using a large pore size membrane to mitigate the membrane fouling problem. A pilot trial of MfMBR process was set up and operated to treat 10 m 3/day of saline wastewater within 4 h. The system was operated under an average permeate flux of 13.1 m3/(m2·day) for 74 days. The average total suspended solids, total chemical oxygen demand, biological oxygen demand, total Kjeldahl nitrogen, and total nitrogen removal efficiencies achieved were 94.3, 83.1, 98.0, 93.1, and 63.3%, respectively, during steady-state operation. The confocal laser scanning microscopy image indicated that the backwash could effectively remove the bio-cake and dead bacteria. Thus, the results showed that the MfMBR process, which is essentially a primary wastewater treatment process, had the potential to yield the same high quality effluent standards as the secondary treatment process; thereby suggesting that it could be used as an option when the economic budget and/or land space is limited. © IWA Publishing 2014.

Conventional membrane bioreactor (MBR) systems have increasingly been studied in recent decades. However, their applications have been limited due to their drawbacks such as low flux, membrane fouling, and high operating cost. In this study, a compact macro-filtration MBR (MfMBR) process was developed by using a large pore size membrane to mitigate the membrane fouling problem. A pilot trial of MfMBR process was set up and operated to treat 10 m 3/day of saline wastewater within 4 h. The system was operated under an average permeate flux of 13.1 m3/(m2·day) for 74 days. The average total suspended solids, total chemical oxygen demand, biological oxygen demand, total Kjeldahl nitrogen, and total nitrogen removal efficiencies achieved were 94.3, 83.1, 98.0, 93.1, and 63.3%, respectively, during steady-state operation. The confocal laser scanning microscopy image indicated that the backwash could effectively remove the bio-cake and dead bacteria. Thus, the results showed that the MfMBR process, which is essentially a primary wastewater treatment process, had the potential to yield the same high quality effluent standards as the secondary treatment process; thereby suggesting that it could be used as an option when the economic budget and/or land space is limited. © IWA Publishing 2014.

This study reports on anaerobic sludge granulation in a laboratory-scale sulfate-reducing up-flow sludge bed (SRUSB) in a novel sulfate reduction, autotrophic denitrification and nitrification integrated (SANI (R)) process for treatment of saline sewage. Granulation occurred in 30 d and reached full development in 90 d. The sulfate-reducing granules grew up to around 1 mm after 90 d with 21 mL/g SVI5 (sludge volume index measured after 5 min) and the biomass concentration reached 29 g/L after 4 months' operation. The reactor removed 89% chemical oxygen demand (COD) and reduced 75% sulfate within 1 h of hydraulic retention time, under a COD loading rate of up to 6.4 kg COD/(m(3).d).

This study reports on anaerobic sludge granulation in a laboratory-scale sulfate-reducing up-flow sludge bed (SRUSB) in a novel sulfate reduction, autotrophic denitrification and nitrification integrated (SANI (R)) process for treatment of saline sewage. Granulation occurred in 30 d and reached full development in 90 d. The sulfate-reducing granules grew up to around 1 mm after 90 d with 21 mL/g SVI5 (sludge volume index measured after 5 min) and the biomass concentration reached 29 g/L after 4 months' operation. The reactor removed 89% chemical oxygen demand (COD) and reduced 75% sulfate within 1 h of hydraulic retention time, under a COD loading rate of up to 6.4 kg COD/(m(3).d).

This study reports on anaerobic sludge granulation in a laboratory-scale sulfate-reducing up-flow sludge bed (SRUSB) in a novel sulfate reduction, autotrophic denitrification and nitrification integrated (SANI (R)) process for treatment of saline sewage. Granulation occurred in 30 d and reached full development in 90 d. The sulfate-reducing granules grew up to around 1 mm after 90 d with 21 mL/g SVI5 (sludge volume index measured after 5 min) and the biomass concentration reached 29 g/L after 4 months' operation. The reactor removed 89% chemical oxygen demand (COD) and reduced 75% sulfate within 1 h of hydraulic retention time, under a COD loading rate of up to 6.4 kg COD/(m(3).d).

Due to the deficiency of fresh water resources, many coastal cities around the world may adopt the practice of using seawater for toilet flushing, which leads to saline wastewaters rich in bromide ions During chlorination for inactivating pathogens in saline wastewater effluents, chlorine can react with bromide and organic matter in the effluents to form halogenated disinfection byproducts Because of the toxicity of residual chlorine to aquatic species, chlorinated saline sewage effluents are required to be dechlorinated before being discharged into coastal marine water In this work, by using a powerful precursor ion scan method with ultra performance liquid chromatography/electrospray ionization triple quadrupole mass spectrometry, the effect of dechlorination time on the speciation and concentrations of halogenated disinfection byproducts in chlorinated secondary saline wastewater effluents was assessed

Due to the deficiency of fresh water resources, many coastal cities around the world may adopt the practice of using seawater for toilet flushing, which leads to saline wastewaters rich in bromide ions During chlorination for inactivating pathogens in saline wastewater effluents, chlorine can react with bromide and organic matter in the effluents to form halogenated disinfection byproducts Because of the toxicity of residual chlorine to aquatic species, chlorinated saline sewage effluents are required to be dechlorinated before being discharged into coastal marine water In this work, by using a powerful precursor ion scan method with ultra performance liquid chromatography/electrospray ionization triple quadrupole mass spectrometry, the effect of dechlorination time on the speciation and concentrations of halogenated disinfection byproducts in chlorinated secondary saline wastewater effluents was assessed

Due to the deficiency of fresh water resources, many coastal cities around the world may adopt the practice of using seawater for toilet flushing, which leads to saline wastewaters rich in bromide ions During chlorination for inactivating pathogens in saline wastewater effluents, chlorine can react with bromide and organic matter in the effluents to form halogenated disinfection byproducts Because of the toxicity of residual chlorine to aquatic species, chlorinated saline sewage effluents are required to be dechlorinated before being discharged into coastal marine water In this work, by using a powerful precursor ion scan method with ultra performance liquid chromatography/electrospray ionization triple quadrupole mass spectrometry, the effect of dechlorination time on the speciation and concentrations of halogenated disinfection byproducts in chlorinated secondary saline wastewater effluents was assessed

This research effort focused on evaluating the toxicity of the saline waste water generated from washing of Indiana Department of Transportation (INDOT) deicing trucks and to study the feasibility of discharging it into wastewater treatment plants. Performance of activated sludge treating wastewater under varying levels of salt concentration was studied by measuring the Chemical Oxygen Demand (COD), activated sludge oxygen uptake rate (OUR) and Turbidity. For the COD tests, wastewater was tested with salt concentrations ranging from 0 mg/L – 1500 mg/L. Within this range there is no impact of salt on COD stabilization, suggesting that the microorganisms are not adversely impacted by salinity in this range. Turbidity tests were conducted for salt concentrations of 0 - 10,000 mg/L. Below a concentration of 3000 mg/ L salt did not have any significant impact on the turbidity. Concentrations above 3000 mg/L aided in flocculation of particles and resulted in faster settling of colloidal solids and reduction in turbidity. Another component of the study was to examine the fate and chemistry of ferric ferro/ferri cyanide, an anti-caking complex that is added to deicing salt. Although, the complex form of cyanide is harmless, in the presence of sunlight it can dissociate to form free cyanide that is highly toxic. Deicing salts collected from INDOT’s West Lafayette and Lafayette Facilities were tested for total and amenable cyanide levels. Lafayette road salt had high levels of cyanide that could lead to violation of pretreatment standards on cyanide, if this salt wash water is discharged to wastewater treatment plant. Respirometry was used for the impact assessment of variable salt concentrations on the biological performance of a low strength activated sludge samples for a POTW using a static liquid – gas flow (GFS) respirometer with salt concentrations varying from 0 – 10% . Generally, positive effect in oxygen uptake rate (OUR) was noticed on low salt concentrations up to

This research effort focused on evaluating the toxicity of the saline waste water generated from washing of Indiana Department of Transportation (INDOT) deicing trucks and to study the feasibility of discharging it into wastewater treatment plants. Performance of activated sludge treating wastewater under varying levels of salt concentration was studied by measuring the Chemical Oxygen Demand (COD), activated sludge oxygen uptake rate (OUR) and Turbidity. For the COD tests, wastewater was tested with salt concentrations ranging from 0 mg/L – 1500 mg/L. Within this range there is no impact of salt on COD stabilization, suggesting that the microorganisms are not adversely impacted by salinity in this range. Turbidity tests were conducted for salt concentrations of 0 - 10,000 mg/L. Below a concentration of 3000 mg/ L salt did not have any significant impact on the turbidity. Concentrations above 3000 mg/L aided in flocculation of particles and resulted in faster settling of colloidal solids and reduction in turbidity. Another component of the study was to examine the fate and chemistry of ferric ferro/ferri cyanide, an anti-caking complex that is added to deicing salt. Although, the complex form of cyanide is harmless, in the presence of sunlight it can dissociate to form free cyanide that is highly toxic. Deicing salts collected from INDOT’s West Lafayette and Lafayette Facilities were tested for total and amenable cyanide levels. Lafayette road salt had high levels of cyanide that could lead to violation of pretreatment standards on cyanide, if this salt wash water is discharged to wastewater treatment plant. Respirometry was used for the impact assessment of variable salt concentrations on the biological performance of a low strength activated sludge samples for a POTW using a static liquid – gas flow (GFS) respirometer with salt concentrations varying from 0 – 10% . Generally, positive effect in oxygen uptake rate (OUR) was noticed on low salt concentrations up to

Amin M.M., Khiadani (Hajian) M.H., Fatehizadeh A., Taheri E. (2014). Validation of linear and non-linear kinetic modeling of saline wastewater treatment by sequencing batch reactor with adapted and non-adapted consortiums. Desalination, 344, 228-235. Available here