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The first application of a novel electro-Fenton (EF) for coking wastewater (CW) treatment at the original pH (6.80) by using tripolyphosphate (TPP) ligand was proposed. Total organic carbon (TOC) decay of CW followed a pseudo-first kinetic rate constant with an apparent rate constant (kapp) of 1.07 × 10−2 min−1 for the EF in the presence of TPP (EF/TPP), which was 2.10 times higher than that of conventional EF (kapp = 5.10 × 10−3 min−1) working at pH 3. The high efficiency of EF/TPP at neutral pH was mainly attributed to the newly formed Fe-O-P coordination in the iron-ligand compound (Fe2+-TPP) supported by UV-absorption spectra results, activating oxygen to produce •OH and hence enhancing the oxidation capacity. Key operating parameters of CW mineralization by EF/TPP including Fe2+ concentration and pH value were systematically investigated. Excitation-emission matrix (EEM) spectra technique was used to assess the variance of dissolved organic matters during the EF/TPP process. Results showed an 81% mineralization of CW after 3 h electrolysis coupled with a low energy consumption (0.129 kWh g−1 TOC) which were obtained by the EF/TPP process. Microtox toxicity demonstrated that TPP could reduce the toxicity of raw CW and importantly, it showed that EF/TPP was effective for detoxification. Mechanism study via simulated matrix with similar components as CW revealed that •OH produced both from Fenton and Fe2+-TPP activation together with the generated active chlorine was responsible for CW mineralization. In summary, the TPP-assisted EF process was presented as a promising technique for extending coking wastewater treatment at near-neutral pH with a high mineralization. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Ultrasonication was successfully used to prepare the composite PVDF/GO membranes. • Largely enhanced hydrophilicity was achieved for the composite membranes. • The composite membrane exhibited excellent adsorption ability toward MB. • The composite membrane showed good regeneration ability and adsorption stability. Abstract In this work, ultrasonication-assisted deposition technology was used to prepare the composite poly(vinylidene fluoride) (PVDF)/graphene oxide (GO) membrane with regarding to organic dyes removal. The electrospun PVDF fibrous membrane, which was first obtained through electrospinning technology, was immersed into the GO aqueous solution, and then the mixture was ultrasonically treated at power of 100 W for different time. Microstructure characterizations and hydrophilicity measurements confirmed that many GO platelets were incorporated into the PVDF membrane. The adsorption ability toward methylene blue (MB) by the composite PVDF/GO membrane was then systematically investigated. The results showed that the ultrasonication time and the concentration of GO in the aqueous solution determined the content of GO in the composite membrane, which also determined the adsorption capacity of the composite membrane. Studies on adsorption kinetics and adsorption isotherms showed that the adsorption behavior of the composite PVDF/GO membrane could be well described by the pseudo second-order model, and the maximum adsorption capacity of MB was 621.1 mg g−1. Furthermore, the composite PVDF/GO membrane exhibited excellent regeneration ability. This work demonstrates that the composite PVDF/GO membrane may be a promising adsorbent to remove organic dyes from wastewater. [ABSTRACT FROM AUTHOR]

Bacteria can coordinate and synchronize activities through a cell density-dependent regulatory mechanism called quorum sensing (QS). Bacteria can measure their population by the synthesis, secretion, and perception of QS signal molecules to regulate specific gene expression when the population reaches a critical threshold. QS participates in various microbial processes such as marine organism bioluminescence, bacterial biofilm formation, and virulence factor expression. The use of QS systems mediated by N-acyl-homoserine lactones and autoinducer-2 has been recently recognized as a promising regulatory approach in environmental science and technology that can intrinsically promote the profound comprehension of wastewater treatment from a microbiology perspective. This article reviewed the study of QS in several environmental systems in wastewater treatment, including systems of aerobic granular sludge, biological nitrogen removal, and bioaugmentation, while several future prospects and suggestions are proposed on the basis of current studies. [ABSTRACT FROM AUTHOR]

An aerobic denitrification system, initially bioaugmented with Pseudomonas strain T13, was established to treat coal-based ethylene glycol industry wastewater, which contained 3219 ± 86 mg/L total nitrogen (TN) and 1978 ± 14 mg/L NO -N. In the current study, a stable denitrification efficiency of 53.7 ± 4.7% and nitrite removal efficiency of 40.1 ± 2.7% were achieved at different diluted influent concentrations. Toxicity evaluation showed that a lower toxicity of effluent was achieved when industry wastewater was treated by stuffing biofilm communities compared to suspended communities. Relatively high TN removal (~50%) and chemical oxygen demand removal percentages (>65%) were obtained when the influent concentration was controlled at below 50% of the raw industry wastewater. However, a further increased concentration led to a 20-30% decrease in nitrate and nitrite removal. Microbial network evaluation showed that a reduction in Pseudomonas abundance was induced during the succession of the microbial community. The napA gene analysis indicated that the decrease in nitrate and nitrite removal happened when abundance of Pseudomonas was reduced to less than 10% of the overall stuffing biofilm communities. Meanwhile, other denitrifying bacteria, such as Paracoccus, Brevundimonas, and Brucella, were subsequently enriched through symbiosis in the whole microbial network. [ABSTRACT FROM AUTHOR]

The coupling process of O 3 /H 2 O 2 -biological aerated filter (BAF) was used to treat biologically treated effluents from traditional Chinese medicine wastewater. Under optimum conditions ( i.e. 20 min of O 3 /H 2 O 2 oxidation, a O 3 dosage (50 mg/L), a 27.5% H 2 O 2 dosage (85 mg/L), pH (7–9), a gas to liquid ratio (3), hydraulic retention of BAF 3 h, temperature (17–26 ℃)), the removal efficiencies for COD and color were 84.6–85.4% and 80.5–83.3%, respectively. The operational cost of the coupling process would be around 0.2198 $/m 3 , the operational cost of the O 3 /H 2 O 2 oxidation stage were 0.2039 $/m 3 and 0.7619 $/kg COD removed, respectively. Moreover based on the experiment conditions and equipment, the COD values at different BAF height was expressed as a function of influent COD concentration, ln C C i = − 1.40 Q C i 0.26 H . The equation may be used to predict the COD removal efficiency at different influent COD values for refinement design of BAF. Finally under optimum conditions, ozone consumption in the O 3 /H 2 O 2 oxidation was 0.20 kg O 3 /kg COD removed, the O 3 /H 2 O 2 oxidation enhanced the wastewater biodegradability from 0.11 to about 0.56, and the inhibitory effect of the O 3 /H 2 O 2 oxidation on microbial growth during subsequent biodegradation accounted for only 8%. [ABSTRACT FROM AUTHOR]

An economical method was proposed to develop an efficient alumina-supported manganese (Mn) and copper (Cu) oxides (Mn-Cu-O/Al2O3) catalyst with a high surface area, 184.06 cm2g−1. The catalyst was utilized for degradation refinery wastewater by heterogeneous catalytic ozonation. The effects of various operating variables including pH, ozone and catalyst dosages, and temperature were systematically investigated in detail to obtain the optimized conditions for accelerated degradation of refinery wastewater. The optimum values were as follows: ozone dose 50.0 mg L−1, catalyst dose 3.0 g L−1, initial pH = 6.8, T = 17 °C. Refinery wastewater samples were analyzed by chemical oxygen demand (COD) and the results indicated that kinetics of COD followed a pseudo–first-order degradation. Moreover, hydroxyl radical mechanism rather than absorption was proposed, indicating that the surface hydroxyl groups were the active sites that played a significant role in catalytic ozonation. [ABSTRACT FROM PUBLISHER]

This work focused on wastewater reclamation of secondary treated ethylene chemical plant effluent, which contained high conductivity and high organic concentration. To reduce the cost and improve operation stability, a biological aerated filter-ultrafiltration-reverse osmosis (BAF-UF-RO) process was proposed. The feasibility and effectiveness of BAF loaded with a novel non-sintered fly-ash ceramsite (NSFC) as a pretreatment method of a dual membrane system were investigated in detail. The results showed that the CODCr, turbidity, NH3-N and the silt density index (SDI) in the effluent from the BAF were reduced to 24.2 mg/L, 12.17 NTU, 0.42 mg/L and 7.52, respectively, and most of the organic compounds were biodegraded. The BAF-UF-RO process was stable with a recovery rate of 75%, and the desalination rate was up to about 97.5%. Compared with the UF-RO process, the operating pressure and backwash frequency decreased from 1.12–1.26 Mpa and 3 times/d to 0.94–0.98 Mpa and 2 times/d, respectively. After continuous operation for four months, there appeared to be no need for chemical cleaning of the RO membrane. Moreover, the analysis results of X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy proved that there was only slight membrane fouling, which was mainly colloidal blocking caused by refractory organic compound. [ABSTRACT FROM PUBLISHER]

In the present study, microcalorimetry was used to monitor the non-growth metabolism of Nitrosomonas europaea ( N. europaea) cells, which could biodegrade the micropollutant (triclosan). The presence of triclosan promote non-growth metabolism and extend the life of N. europaea cells. However, at high concentration of triclosan (4 mg L), the acute toxicity was induced in cells. The addition of allylthiourea inhibited the non-growth metabolism of N. europaea, suggesting that ammonia monooxygenase is responsible for the biodegradation of triclosan. Scanning electron microscopy result showed the cell membrane damage induced by triclosan. It is concluded that triclosan would bind to ammonia monooxygenase on the cell membrane and cause acute toxicity. Triclosan (<1.0 mg L) is favor for the non-growth metabolism, while high concentration (4.0 mg L) is toxic to N. europaea cells. [ABSTRACT FROM AUTHOR]

Indole and phenol often coexist in the coking wastewater, while the effects of phenol on microbial communities of indole metabolism were less explored. In this study, the microbial interactions within activated sludge microbial communities stimulated by indole (group A) or by indole and phenol (group B) were systematically investigated in sequencing batch reactors (SBRs). The results showed that the removal of indole was increased by adding phenol. By using high-throughput sequencing technology, it was found that α-diversity was reduced in both groups. According to the relative abundance analysis, the indole-degrading genus Comamonas was the core genus in both groups (33.94% and 61.40%). But another indole-degrading genus Pseudomonas was only enriched in group A with 12.22% relative abundance. Meanwhile, common aromatic degrading genus Dyella and Thermomonas were enriched only in group B. It was found that the relative abundance of cytochrome P450 and styrene degradation enzymes were increased in group B by PICRUSt analysis. Based on the phylogenetic molecular ecological networks (pMENs), module hub OTU_1149 (Burkholderia) was only detected in group B, and the positive interactions between the key functional genus Burkholderia and other bacteria were increased. This study provides new insights into our understanding of indole metabolism communities stimulated by phenol, which would provide useful information for practical coking wastewater treatment. • We explored the response of microbial communities under indole and phenol stress. • The removal of indole was increased by adding phenol. • Indole-degrading genus Comamonas was the core genus in both groups. • The phenol-stimulated activated sludge could produce more key enzymes. • Phenol had an active effect on the increase of positive interactions in the network. [ABSTRACT FROM AUTHOR]

The influences of different fixed ways of polyurethane on the purification performance of wastewater treatment in biological contact oxidation were discussed, the polyurethane was put into biological contact oxidation by up-floating, sinking and general up-floating general sinking respectively, the relationship between microbial community structure and purification performance was analyzed. The results showed that polyurethane fixed by general up-floating general sinking could most efficiently remove pollutants, the purification rate of COD and NH4+ -N were 90% and 94% ; the attached microbial populations were with the largest number, the highest diversity, the strongest activity and the most reasonable function in this way. Therefore, the purification performance was affected by the fixed way of polyurethane in biological contact oxidation and the general up-floating general sinking was the most effective fixed way. [ABSTRACT FROM AUTHOR]

The Fe/C micro-electrolysis and Fenton combined process was used to solve the high yield organic CLT acid wastewater in our country. The influence factors of pH, reaction time, ratio of iron and coke, H2O2 dosage and reaction time of H2O2 were investigated. The results show that when the influent COD is 28.1 g/L to 34.5 g/L, pH is 2.5, ratio of iron and coke is 2:1 and the reaction time is 60 min, the removal rate of COD by ferric-carbon micro-electrolysis is above 30%. For treatment with the Fenton when the H2O2 (30%) dosage is 0.15 mol/L, the reaction time is 60 min and the temperature is 20 to 30°C, the removal rate of COD reaches more than 43%, B/C ratio of wastewater increases from 0.08 to 0.43. [ABSTRACT FROM AUTHOR]

To reveal the relationship between microorganism and pollutants' degradation in the stability system of the municipal wastewater treatment plant, the dynamic monitoring of microbial community structure and metabolic activity of the stable operation biological system in biological wastewater treatment plant was carried out using the denaturing gradient gel electrophoresis (PCR - DGGE) and Biology Technology. The results showed that the average removal efficiency of effluent Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and TN was more than 84.4%, 84.7% and 59.8%, respectively. The microbial community structure was stable in the different sites of biological system in the same season, and the ecological niche of predominant functional species including Bacillus , Pseudomonas, Aeromonas was stable. As the temperature increased in spring, the quantity and diversity of population increased significantly. Meanwhile, metabolic activity strengthened in biological system, which could improve the removal rates of pollutants. It is feasible to use the two methods to monitor the changes of microbial community structure of biological system in a wastewater treatment plant at low temperature. [ABSTRACT FROM AUTHOR]

To further promote the water pollution control of Northeast China, to ensure the water environmental safety of Songhua river and Liaohe river, and to accelerate the harmonious development of economy, society and environment in Northeast China, the performances of 32 typical municipal wastewater treatment plants (MWWTPs) located in 13 key cities of Liaoning, Jilin and Heilongjiang were investigated and analyzed. General problems generated in the operation and management of these MWWTPs were found out, and the corresponding strategies for their stable performances were proposed. These provide guidance from the perspective of water pollution control for the sustainable development and benign circulation of the economy in Northeast China. [ABSTRACT FROM AUTHOR]

In order to analyze the urban wastewater treatment efficiency in northeast China more effectively, this paper uses correlation analysis to determine the efficiency of various relevant factors, combined with second-order quadratic approximation of the investment and operation cost function to fit the actual data, based on which the efficiency of wastewater treatment is analyzed with corresponding indexes. The result shows that the analysis of urban wastewater treatment efficiency in northeast China should be concentrated on designed capacity, actual processing capacity, effluent COD concentration and sludge treatment volume. All the indices above have a positive relation with investment and operation cost, and the margin cost shows a decreasing trend, which means that the efficiency of urban wastewater treatment in northeast China is improved with increasing cost. [ABSTRACT FROM AUTHOR]

This paper discusses the mechanism and application of denitrification inhibition to the activity of sulfate - reducing bacteria in wastewater treatment of domestic and overseas oilfields. All factors affecting this process and shortcomings in the process were reviewed as well. It is suggested that the study on protein structure and environmental gene is important for the mechanism research, particularly for studying the effect of addition of inhibiting agents, such as nitrate and denitrifying bacteria, on the gene and protein structure of sulfate - reducing bacteria as well as the metabolism process. It is critical to investigate this process from the view of microbial molecular ecology. The case application has also been studied for Daqing Oilfield. [ABSTRACT FROM AUTHOR]

The attachment and colonization process of microorganisms on a carrier is an interdisciplinary research field. Through a series of physical, chemical, and biological actions, the microorganisms can eventually reproduce on the carrier. This article introduces biofilm start-up and its applications, and explores the current issues to look forward to future development directions. Firstly, the mechanism of microbial film formation is analyzed from the microbial community colonization and reproduction process. Secondly, when analyzing the factors influencing microbial membrane formation, the effect of microbial properties (e.g., genes, proteins, lipids) and external conditions (i.e., carrier, operating environment, and regulation mechanism among microbial communities) were discussed in depth. Aimed at exploring the mechanisms and influencing factors of biofilm start-up, this article proposes the application measures to strengthen this process. Finally, the problems encountered and the future development direction of the technology are analyzed and prospected. [Display omitted] • Introduced the mechanism of biofilm initiation and colonization in more detail. • Considering the potential enhanced colonization measures of biofilms in wastewater treatment. • Put forward specific opinions on the development opportunities of biofilm combined with current technical challenges. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, bioaugmentation was applied to upgrade a full-scale activated sludge system (S2) into a contact oxidation system (S1). Results showed that when chemical oxygen demand (COD) and ammonia nitrogen (-N) concentration of the petrochemical wastewater were 320–530mg/L and 8–25mg/L, respectively, the bioaugmented process (S1) took only 20 days when they were below 80mg/L and 10mg/L, respectively. However, the unbioaugmented conventional activated sludge process (S2) spent 30 days to reach the similar effluent quality. As the organic loading rate (OLR) increased from 0.6 to 0.9 and finally up to 1.10kg COD/m3 d, S1 showed strong resistance to shock loadings and restored after three days compared to the seven days required by S2. Based on the results of this paper, it shows that bioaugementation application is feasible and efficient for the process upgrade due to the availability of the bioaugmented specialized consortia. [Copyright &y& Elsevier]

Background: The isolation of atrazine-degrading microorganisms with specific characteristics is fundamental for bioaugmenting the treatment of wastewater containing atrazine. However, studies describing the specific features of such microorganisms are limited, and further investigation is needed to improve our understanding of bioaugmentation. Results and conclusions: In this study, strain Arthrobacter sp. ZXY-2, which displayed a strong capacity to degrade atrazine, was isolated and shown to be a potential candidate for bioaugmentation. The factors associated with the biodegrading capacity of strain ZXY-2 were investigated, and how these factors likely govern the metabolic characteristics that control bioaugmentation functionality was determined. The growth pattern of Arthrobacter sp. ZXY-2 followed the Haldane–Andrews model with an inhibition constant (Ki) of 52.76 mg L−1, indicating the possible augmentation of wastewater treatment with relatively high atrazine concentrations (> 50 ppm). Real-time quantitative PCR (RT-qPCR) results showed a positive correlation between the atrazine degradation rate and the expression levels of three functional genes (trzN, atzB, and atzC), which helped elucidate the role of strain ZXY-2 in bioaugmentation. In addition, multiple copies of the atzB gene were putatively identified, explaining the higher expression levels of this gene than those of the other functional genes. Multiple copies of the atzB gene may represent a compensatory mechanism that ensures the biodegradation of atrazine, a feature that should be exploited in future bioaugmentation applications. [ABSTRACT FROM AUTHOR]

Mycelial pellets, as a novel biomass material, can adsorb pollutants as a biosorbent, or combine other substances and organisms to form self‐immobilized biomixture (SIB) to remove pollutants from wastewater. The pellets are eco‐friendly, have a good self‐immobilization capacity, and are easy to filter. In addition, some mycelial fungi can remove the pollutants in water through biodegradation. This study reviewed biomixture based on mycelial pellets and the two ways, through which SIB remove pollutants in water: pure pellets and the pellets with other materials. The characteristics and functions of each part of SIB were discussed. The study also highlighted the shortcomings of the technology and provided recommendations for further development of this technology. [ABSTRACT FROM AUTHOR]

Bioaugmentation by adding well-functioning mixed microorganism consortia represents a potentially useful approach to improve contaminant removal in wastewater treatment plants (WWTPs). However, unfavorable environmental conditions (i.e., low temperatures) can severely inhibit microbial activity, drawing our attention to constructing cold-tolerant microorganism preparations and investigating their availability in practical applications. Here we screened four in situ functional isolates from the activated sludge of secondary sedimentation tanks in WWTPs to construct a psychrophilic microbial consortium, which was used to perform bioaugmentation for enhanced removal of nitrogen and phosphorus under low temperatures. The consortium was established by cocultivation of four isolates, characterized by 16 S rRNA as the COD-degrading bacterium Aeromonas sp. Z3, aerobic denitrifying bacterium Acinetobacter sp. HF9, nitrifying bacterium Klebsiella sp. X 8, and polyphosphate-accumulating bacterium Pseudomonas sp. PC5 respectively. The microorganism preparation was composed of Z3, HF9, X 8, and PC5 under the ratio of 1: 1: 3: 1, which can exert optimal pollutant removal under the conditions of 12 °C, 6.0–9.0 pH, 120–200 r‧min−1, and a dosage of 5% (V/V). A 30-day continuous operation of the bioaugmented and control sequencing batch reactors (SBRs) was investigated, and the bioaugmented SBR showed a shorter start-up stage and a more stable operating situation. Compared to the control SBR, the COD, NH 4 +-N, TN, and TP removal efficiency of the bioaugmented SBR increased by an average of 7.95%, 9.05%, 9.54%, and 7.45% respectively. The analysis of the microbial community revealed that the introduced isolates were dominant in the activated sludge and that functional taxa such as Proteobacteria , Bacteroidota, and Actinobacteria were further enriched after a period of bioaugmentation. The study provides some basis and guidance for the practical application of how to strengthen the stable operation of WWTPs under low temperatures. [Display omitted] • A microbial consortium consists of four in situ screening isolates. • Constructed microorganism preparation eliminates multiple pollutants efficiently. • The performance of SBR improved markedly under low temperature by bioaugmentation. [ABSTRACT FROM AUTHOR]

Abstract: Chinese traditional medicine wastewater, rich in macromolecule and easy to foam in aerobic biodegradation such as Glycosides, was treated by two identical bench-scale aerobic submerged membrane bioreactors (SMBRs) operated in parallel under the same feed, equipped with the same electronic control backwashing device. One was used as the control SMBR (CSMBR) while the other was dosed with powdered activated carbon (PAC) (PAC-amended SMBR, PSMBR). The backwashing interval was 5 min. One suction period was about 90 min by adjusting preestablished backwashing vacuum and pump frequency. The average flux of CSMBR during a steady periodic state of 24 d (576 h) was 5.87 L/h with average hydraulic residence time (HRT) of 5.97 h and that of PSMBR during a steady periodic state of 30 d (720 h) was 5.85 L/h with average HRT of 5.99 h. The average total chemical oxygen demand (COD) removal efficiency of CSMBR was 89.29% with average organic loading rate (OLR) at 4.16 kg COD/(m3-d) while that of PSMBR was 89.79% with average OLR at 5.50 kg COD/(m3-d). COD concentration in the effluent of both SMBRs achieved the second level of the general wastewater effluent standard GB8978–1996 for the raw medicine material industry (300 mg/L). Hence, SMBR with electronic control backwashing was a viable process for medium- strength Chinese traditional medicine wastewater treatment. Moreover, the increasing rates of preestablished backwashing vacuum, pump frequency, and vacuum and flux loss caused by mixed liquor in PSMBR all lagged compared to those in CSMBR; thus the actual operating time of the PSMBR system without membrane cleaning was extended by up to 1.25 times in contrast with the CSMBR system, and the average total COD removal efficiency of PSMBR was enhanced with higher average OLR. [Copyright &y& Elsevier]

In the global effort to reduce CO 2 emissions, the concurrent enhancement of pollutant degradation and reductions in fossil fuel consumption are pivotal aspects of microalgae-mediated wastewater treatment. Clarifying the degradation mechanisms of bacteria and microalgae during pollutant treatment, as well as regulatory biolipid production, could enhance process sustainability. The synergistic and inhibitory relationships between microalgae and bacteria are introduced in this paper. The different stimulators that can regulate microalgal biolipid accumulation are also reviewed. Wastewater treatment technologies that utilize microalgae and bacteria in laboratories and open ponds are described to outline their application in treating heavy metal-containing wastewater, animal husbandry wastewater, pharmaceutical wastewater, and textile dye wastewater. Finally, the major requirements to scale up the cascade utilization of biomass and energy recovery are summarized to improve the development of biological wastewater treatment. [Display omitted] • The synergistic and antagonistic interactions between bacteria and microalgae are summarized. • Different stimulators that could regulate microalgal biolipid accumulation are also reviewed. • Wastewater treatment technologies that utilize microalgae and bacteria in the laboratory and open ponds are described. • The trends in microalgae-bacterial consortium in multistage energy production are proposed. [ABSTRACT FROM AUTHOR]

The C/N ratio in wastewater differs in place and time and affects the nitrogen removal performance of wastewater treatment. However, studies have focused only on the direct relationship between C/N and nitrogen removal efficiency but disregarded the significant role of soluble microbial products (SMPs) as an intermediate electron station. In this work, the contribution of SMPs to TN removal for treating wastewater with different C/N in a sequencing batch reactor (SBR) was investigated to extend relevance from C/N–TN removal to C/N–SMP–TN removal. TN removal efficiency was improved by increasing the influent C/N. The relative contribution of SMPs increased from 15% (C/N = 2) to 54% (C/N = 8), including 25.5% via utilization-associated product (UAP)-dependent denitrification and 28.5% via biomass-associated product (BAP)-dependent denitrification. The direct contribution of influent organic substrates dramatically decreased from 85.1% to 46%. In addition, providing an anoxic phase effectively enhanced BAP-dependent denitrification and achieved an increment of the SMP absolute contribution from 20.3% to 43% at C/N = 8 with 6.7 mg/L of TN additionally removed. This work clarified the significant contribution of SMPs to the nitrogen removal process, particularly in treating wastewater with high C/N. It also presented a new strategy for improving nitrogen removal performance via SMP reclamation. • The amount of production and reutilization of SMP increased with higher C/N. • Increasing C/N enlarged the contribution of SMP to TN removal. • SMPs contributed more than IOSs under high C/N condition. • Anoxic phase enhanced BAP-dependent denitrification under high C/N condition. [ABSTRACT FROM AUTHOR]

• Self-immobilized biomixture was prepared for degradation of atrazine. • Adsorption of biochar by pellets followed pseudo-second-order kinetic model. • Biochar improved atrazine removal ability and reusability of biomixture. • Agrobacterium sp. WL-1 significantly enhanced ATZ degradation ability of Arthrobacter sp. ZXY-2 of ATZ. • ATZ intermediate metabolite were examined. A self-immobilization method for microorganisms was developed based on fungal pellets. Generally, pellets have some problems such as cell leakage, cell loading limitation and low mechanical strength. Therefore, biochar was applied to overcome these disadvantages. Atrazine degradable microorganism Arthrobacter sp. ZXY-2 was immobilized by Aspergillus niger Y3 pellets. After adding biochar with optimal dosage (0.006 g biochar for 0.3 g pellets with ZXY-2), the self-immobilized biomixture (SIB) removed 50 mg /L atrazine rapidly within 1 h, which was 61% higher compared to pellets without biochar. The kinetic adsorption results showed that the biosorption of biochar by pellets followed a pseudo-second-order kinetic model. The ATZ removal ability and reusability of SIB were significantly increased by biochar. The results showed that the addition of biochar could enhance the connection between ZXY-2 and pellets based carrier, and the favorable biodegradation pH of ZXY-2 changed to 6 and 10. Several analyses such as ζ-potential measurements, FTIR, XPS, SEM-EDS, and elemental analyses were performed to evaluate the mechanism of action of SIB. To enhance the ATZ degradation by single strain, Agrobacterium , sp WL-1 was isolated and added. The metabolic pathways and their function complementation were studied. Furthermore, a biomass integration model for wastewater treatment was proposed herein. [ABSTRACT FROM AUTHOR]

Aquabacterium parvum strain B6 exhibited efficient nitrate-dependent Fe(II) oxidation ability using nitrate as an electron acceptor. A continuous up-flow bioreactor that included an aerobic and an anoxic section was constructed, and strain B6 was added to the bioreactor as inocula to explore the application of microbial nitrate-dependent Fe(II) oxidizing (NDFO) efficiency in wastewater treatment. The maximum NRE (anoxic section) and TNRE of 46.9% and 79.7%, respectively, could be obtained at a C/N ratio of 5.3:1 in the influent with HRT of 17. Meanwhile, the taxonomy composition of the reactor was assessed, as well. The NDFO metabolism of strain B6 could be expected because of its relatively dominant position in the anoxic section, whereas potential heterotrophic nitrification and aerobic denitrification developed into the prevailing status in the aerobic section after 50 days of continuous operation. [ABSTRACT FROM AUTHOR]

In this study, phenol wastewater treatment systems treated with different concentrations of single-walled carbon nanotubes (SWCNTs) (0–3.5 g/L) were exposed to phenol and carbon nanotubes (CNTs) shock loadings to investigate the long-term impacts of SWCNTs on microbial communities. Phenol removal remained high efficiency (>98%) in SWCNTs-treated groups but decreased in non-treated group (85.1 ± 1.9%) when exposed to high concentration of phenol (500 mg/L). However, secondary dosing of SWCNTs in SWCNTs-treated groups would decrease the phenol removal efficiency. Illumina MiSeq sequencing revealed that the diversity, richness and structure of microbial communities were shifted under phenol shock loading, especially under high phenol concentration, but not under CNTs shock loading. In response to phenol and CNTs shock loadings, Rudaea , Burkholderia , Sphingomonas , Acinetobacter , Methylocystis and Thauera became dominant genera, which should be involved in phenol removal. These results suggested that a proper amount of SWCNTs might have positive effects on phenol wastewater treatment systems. [ABSTRACT FROM AUTHOR]

In this study, zeolite-biological aerated filters (Z-BAFs) bioaugmented by free and magnetically immobilized cells of Arthrobacter sp. W1 were designed to treat coking wastewater containing high concentrations of phenol and naphthalene along with carbazole (CA), dibenzofuran (DBF), and dibenzothiophene (DBT). All treatments were carried out for a period of 100 days and the data indicated that bioaugmented Z-BAFs with magnetically immobilized cells was most efficient for treating coking wastewaters. Illumina high-throughput sequencing was used to reveal the microbial community structures of Z-BAFs. Both bioaugmentation treatments could accelerate the shift of the bacterial community structures. The introduced strain W1 remained dominant in the bioaugmented Z-BAFs with magnetically immobilized cells, indicating both strain W1 and the indigenous degrading bacteria played the most significant role in the treatment. Overall, bioaugmented Z-BAF with magnetically immobilized cells can be used to efficiently degrade phenol, naphthalene, CA, DBF, and DBT in coking wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Analysis of research hotspots and trends of mycelial pellets as biocarriers. • Clarified the reason and mechanism of mycelial pellets as biocarriers. • Summarized the application in wastewater and recovery for resource and energy. • Presented the prospects and trends of mycelial pellets as biocarriers. Mycelial pellets, a new environment friendly biological carrier, have received wide attention from researchers due to porosity, stability and unique biocompatibility. In this article, the theoretical basis and mechanism of mycelial pellets as a biological carrier were analyzed from the properties of mycelial pellets and the interaction between mycelial pellets and other microorganisms. This article aims to collate and present the current application and development trend of mycelial pellets as biological carriers in wastewater treatment, resource and energy recovery, especially the symbiotic particle system formed by mycelial pellets and microalgae is an important way to break through the technical bottleneck of biodiesel recovery from wastewater. This review also analyzes the research hotspots and trends of mycelial pellets as carriers in recent years, discusses the challenges faced by this technology, and puts forward corresponding solutions. [ABSTRACT FROM AUTHOR]

Carbamazepine is frequently detected in waters and hardly eliminated during conventional wastewater treatment processes due to its complicated chemical structure and resistance to biodegradation. A carbamazepine-degrading bacterium named CBZ-4 was isolated at a low temperature (10°C) from activated sludge in a municipal wastewater treatment plant. Strain CBZ-4, which can use carbamazepine as its sole source of carbon and energy, was identified as Pseudomonas sp. by the 16S rRNA gene sequence. The composition and percentage of fatty acids, which can reveal the cold-adaptation mechanism of strain CBZ-4, were determined. Strain CBZ-4 can effectively degrade carbamazepine at optimal conditions: pH 7.0, 10°C, 150 r/min rotation speed, and 13% inoculation volume. The average removal rate of carbamazepine was 46.6% after 144 hr of incubation. The biodegradation kinetics of carbamazepine by CBZ-4 was fitted via the Monod model. V max and K s were found to be 0.0094 hr −1 and 32.5 mg/L, respectively. [ABSTRACT FROM AUTHOR]

Abstract: To accelerate the start-up of biological municipal wastewater treatment processes at low temperatures and ensure their daily stable performances, bioaugmentation was adopted with the addition of specialized mixed bacteria. As a result, three types of biological processes were successfully started within 15days and showed stable and efficient daily performances. Results of PCR–DGGE analysis demonstrated the long-term predominance of the bioaugmented specialized bacteria in the bioaugmented systems. And results of BIOLOG analysis showed that the bacterial community structure and catabolic capability of the biological systems varied with wastewater temperature variations. However, the stability of the bacterial community under normal operating conditions and adaptability to perturbations enabled the long-term stable and efficient performances of the biological systems. In conclusion, bioaugmentation was successful for rapid start-up and stable performances of three typical biological municipal wastewater treatment processes at low temperatures. [Copyright &y& Elsevier]

Abstract: In this study, decolorization of Reactive Brilliant Red X-3B wastewater by the biological process coping with high salinity and metal ions conditions was investigated, and 16S rDNA based fingerprint technique was used to investigate microbial population dynamics. Results of sequencing batch tests showed that the microbial community could keep efficient with high concentration of dye (1100mgL−1), salt (150gL−1 NaCl) and some metal ions such as Mg2+, Ca2+ (1–10mmolL−1) and Pb2+ (1mmolL−1). 16S rDNA-based molecular analysis techniques demonstrated that the microbial community shifted during the acclimatization process affected by salt or metal ions. Some stains similar to Bacillus, Sedimentibacter, Pseudomonas, Clostridiales, Streptomyces and some uncultured clones acted for the dynamic succession, supposed as potential decolorization bacteria. This study provided insights on the decolorization capability and the population dynamic shifts during decolorization process of azo dye wastewater coping with salt and metal ions. [Copyright &y& Elsevier]

In this study, mycelial pellets (MPs) were employed as efficient and sustainable bio-carriers to alleviate membrane fouling in membrane bioreactor (MBR). The comparative study was performed in lab-scale MBR in the absence and presence of MPs addition under continuous operation for 80 days. The results demonstrated efficient removal of chemical oxygen demand (COD) and ammonia nitrogen (NH 4 +-N) for both systems, while MPs addition led to lower rate at which transmembrane-pressure was increased, lower filtration resistance, thinner bio-cakes and fewer contents of extracellular polymeric substances (EPS) and soluble microbial products (SMP) in bio-cakes of membrane surface. Adding MPs into MBR could enhance biomass retention and EPS content in suspended liquid, thus accelerating the granulation of activated sludge, which should be responsible for mitigation of membrane fouling. According to the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, the total surface free energy between membrane and foulants was always attractive, but total interfacial interaction especially acid-based (AB) interaction in the presence of MPs was weaker than that in the absence, confirming lower adhesion force induced by MPs. Furthermore, high throughput sequencing analysis of bio-cakes illustrated that a smaller relative abundance of EPS producer including the classes Gammaproteobacteria , Alphaproteobacteria and Actinobacteria , and a higher abundance of SMP decomposer including the class Chloroflexia were observed. The relevant mechanisms were underlined schematically to explain the function of MPs in mitigating membrane fouling process, which could be attributed to formation of biofilm with MPs serving as bio-carriers followed by promoted sludge granulation. This study provides a proof-in-concept demonstration of using MPs as bio-carriers to mitigate membrane fouling, making wastewater treatment by MBR more efficient, more reliable and more sustainable. [Display omitted] •MPs were employed as efficient bio-carriers to alleviate membrane fouling. •The presence of MPs promoted sludge granulation. •MPs addition reduced the deposition of flocs sludge on membrane surface. •MPs addition led to lower filtration resistance and fewer foulants. [ABSTRACT FROM AUTHOR]

Facing low reactivity/selectivity of oxygen reduction reaction (ORR) in electro-Fenton (EF), N, S atoms were introduced into carbon-based cathode. "End-on" O 2 adsorption was achieved by adjusting electronic nature via N doping, while *OOH binding capability was tuned by spin density variation via S doping. Results showed the optimized N, S co-doped cathode presented a 42.47% improvement of H 2 O 2 accumulation (7.95 ± 0.02 mg L−1 cm−2). According to density functional theory (DFT), N, S co-doped structure favored the "end-on" O 2 adsorption as adsorption energy dropped to − 2.24 eV. Moreover, O-O/C-O bond lengths variation proved a possibility for *OOH desorption. The elaborated cathode was used in EF for sulfonamides (SAs) decay. A 100% removal rate of sulfadiazine (SDZ), sulfathiazole (STZ) and sulfadimethoxine (SDM) was achieved within 60 min, among which SDZ tended to be degraded easily. Because the absolute hardness (η) of those pollutants is ranked as follows: η SDM > η STZ > η SDZ. Degradation pathways were proposed based on the detected byproducts, along with toxicity was evaluated by ecological structure-activity relationship (ECOSAR) program. Results showed that toxic intermediates generated were reduced or even disappeared. EF with N, S co-doped cathode provides a promising process for antibiotics wastewater treatment. ga1 • N, S co-doping experienced a 42.47% improvement in H 2 O 2 accumulation. • O 2 adsorption energy dropped to − 2.24 eV based on DFT calculation. • O-O/C-O bond lengths variation favored *OOH desorption. • Absolute hardness (η) of the three pollutants is ranked as η SDM > η STZ > η SDZ. • Degradation pathways and toxicity evolution were evaluated. [ABSTRACT FROM AUTHOR]

Aerobic granular sludge (AGS) is promising in wastewater treatment. However, the formation and existence of AGS under low organic loading rate (OLR) is still not fully understood due to a knowledge gap in the variations and correlations of N -acyl-homoserine lactones (AHLs), the microbial community, extracellular polymeric substances (EPS) and other physiochemical granule properties. This study comprehensively investigated the AHL-mediated quorum sensing (QS) and microbial community characters in the AGS fed with ammonium-rich wastewater under a low OLR of 0.15 kg COD (m3 d)−1. The results showed that the AGS appeared within 90 days, and the size of mature granules was over 700 μm with strong settleability and ammonium removal performance. More tightly-bound extracellular polysaccharide and tightly-bound extracelluar protein were produced in the larger AGS. C10-HSL and C12-HSL gradually became dominant in sludge, and short-chain AHLs dominated in water. EPS producers and autotrophic nitrifiers were successfully retained in the AGS under low OLR. AHL-mediated QS utilized C10-HSL, C12-HSL and 3OC6-HSL as the critical AHLs to regulate the TB-EPS in aerobic granulation, and autotrophic nitrifiers may perform interspecific communication with C10-HSL. The correlations of bacterial genera with AGS properties and AHLs were complex due to the dynamic fluctuations of microbial composition and other variable factors in the mixed-culture system. These findings confirmed the participation of AHL-mediated QS in the regulation of microbial community characters and AGS properties under low OLR, which may provide guidance for the operation of AGS systems under low OLR from a microbiological viewpoint. Unlabelled Image • Successful aerobic granulation is achieved at a low OLR of 0.15 kg COD (m3 d)−1. • EPS producers and autotrophic nitrifiers successfully survive under low OLR. • AHL-mediated QS regulates the EPS production with 3OC6-HSL, C10-HSL and C12-HSL. • Autotrophic nitrifiers may perform interspecific communication with C10-HSL. [ABSTRACT FROM AUTHOR]