The accumulation of endogenous ammonia nitrogen in anaerobic digestion (AD) is widely recognized as a critical factor inhibiting methanogenesis. Gas-permeable membranes (GPM), leveraging their selective permeation properties, provide a large gas-liquid mass transfer interface and demonstrate significant potential in preventing ammonia accumulation. In this study, integrating GPM into AD achieved in situ ammonia removal and recovery, fundamentally alleviating ammonia inhibition and enabling ammonia valorization. GPM reactors (with H2SO4 absorption/vacuum distillation) maintained ammonia at 1300-1500 mg/L (vs. >5000 mg/L in controls) and sustained biogas yield 0.67-0.72 L/g VS at 7 g VS/(L·d) OLR (controls inhibited at 5 g VS/(L·d)). Multi-omics revealed microbial mechanisms: community-dominant Methanobacterium contributed little to methanogenesis, while functionally dominant Methanothrix retained robust activity via dual methanogenic pathways and upregulated biosynthesis-related proteins. This study validates GPM-AD efficacy and provides theoretical support for optimization.

Iron/copper (Fe/Cu) bimetallic particles have demonstrated high activity for the dechlorination of trichloroacetaldehyde (TCAL). To enhance the dechlorination efficacy, a systematic evaluation of key operational parameters—such as chelator concentration, bimetal dosage, copper loading, and initial pH—is essential. The Fe/Cu bimetallic composites were synthesized and applied under optimized conditions (25 g/L Fe/Cu, EDTA/Cu molar ratio of 1:10, 1% Cu loading, initial pH 8). The materials were characterized before and after reaction using SEM-EDS, XRD, and XPS. Reaction intermediates were analyzed by gas chromatography with a micro electron capture detector (GC-μECD) to propose a degradation pathway. Under optimal conditions, a high TCAL removal rate of 98.18% and a dechlorination efficiency of 38.70% were achieved within 48 hours. Material characterization confirmed an iron-core structure with surface-deposited copper, which facilitated synergistic galvanic corrosion and improved surface reactivity. The degradation was attributed to hydrogen radicals (H•), the reducing power of Fe⁰ and Fe²⁺, and the adsorption by iron oxides (Fe₂O₃ and FeOOH). The Fe/Cu catalyst exhibited excellent recyclability over five cycles, and the degradation kinetics followed a pseudo-first-order model.

This research introduces an innovative series-connected two-stage submerged gas permeable membrane (STSGPM) system for anaerobic digestate treatment, integrating ammonia recovery, digestate concentration, and water reclamation. The system achieved over 99 % ammonia removal across various temperature gradients, with the 65/55/25 degrees C gradient showing optimal water flux, where the average water flux of the first-stage SGPM (SGPM1) was recorded at 3.43 L/m2/h, while the second-stage SGPM (SGPM2) maintained a consistent flux of 4.25 L/m2/h. STSGPM achieved interception rates of 99.8 % and 99.41 % for inorganic ions and organic matter, respectively. After 10 cycles, SGPM2 remained stable, but SGPM1 experienced fouling from gel-like organic deposits (proteins, microbial products, fulvic acid), which were fully removed post-cleaning. The high-purity (NH4)2SO4, the concentrated digestate meeting agricultural standards, and the reclaimed water compliant with urban miscellaneous water use standards highlight the effective reutilization of the three by-products. This aligns with the zero-discharge objective, underscoring the potential of STSGPM to advance resource recovery from anaerobic digestate. Additionally, the recovery of (NH4)2SO4 and high-quality water generates potential profits, reducing the net operating cost of the STSGPM system to $0.155 per kilogram of NH3 recovery. Overall, the STSGPM process represents a cost-effective and efficient ammonia recovery strategy with significant potential for widespread application.

To explore how biochar influences nitrogen cycling in unsaturated, capillary, and saturated zones of partially saturated vertical flow constructed wetlands (VFCWs), three parallel VFCWs were established to examine the effects of biochar's better water holding capacity on nitrogen removal and N2O emissions. Microbial mechanisms involved were studied by conducting ETS activity, metagenomic sequencing and performing high-throughput sequencing of 16S rRNA. Results indicated that the combination of adding 40 % biochar and maintaining water level of 45 cm facilitated TN removal and suppressed N2O emissions, achieving TN removal efficiency of 73.4 % and N2O/removed TN value of 0.3 %. Within the unsaturated zone, the relative abundance of amoA, hao, and nxrB increased by 929 %, 454 %, and 38.3 %, respectively, enhancing nitrification capacity microorganisms carrying these genes and involved in the oxidation of NH4+-N to NO3--N included Nitrosomonas, Methylosarcina, Nitrosospira, and Methylomonas, whose relative abundance increased by 75.2 %. In the capillary zone, the 19.2 % increase in nosZ (involved in the reduction of N2O to N2) transformed it into a potential N2O consumption layer. The functional genera involved in N2O reduction (Ferrovibrio, Thauera, Ramlibacter, and Hyphomicrobium) in the capillary zone increased by 1724 %, 357 %, 707 %, and 78.5 %, respectively, and the ETS activity in the 40W-CW capillary zone was 72.5 % higher than that of QS-CW. Within the saturated zone, the relative abundance of amoA increased by 591 %, hao by 149 %, and nxrB decreased by 20.0 %, potentially facilitating short-cut denitrification.

Hydrolysis acidification (HA), an efficient biological pretreatment technology, has demonstrated significant potential in degrading toxic and recalcitrant compounds. In this study, the reaction efficiency was utilized to investigate the toxic and inhibitory effects of trichloroethylene (TCE) on HA during the co-metabolism of phenol and benzoic acid. Results indicated that high TCE concentrations exerted an inhibitory effect on HA, with an EC50 value of 75 mg/L. Phenol and benzoic acid as co-metabolized substrates for HA exhibited a unique response to the toxicity of TCE, that increasing concentrations of phenol and benzoic acid enhanced the dechlorinating degradation of TCE by promoting secretion of extracellular polymeric substance (EPS), however, causing partial cell death. At a TCE concentration of 75 mg/L, when the concentrations of phenol and benzoic acid were 375 mg/L, the dechlorination efficiencies of TCE were 58.53 % and 49.71 %, the acid yields were 60.35 and 50.93 mg COD/g VSS, the EPS concentrations were 40.16 and 33.77 mg COD/g VSS, the DNA concentrations in solution were 10.45 and 10.97 mg COD/g VSS(significantly higher than blank control group: 8.97 mg COD/g VSS), respectively. This enhancing effect was consistently observed across various concentrations of phenol and benzoic acid, and dechlorination degradation of TCE has also been effectively improved. The unique toxic response may be attributed to the compact structure of granular sludge and the increased secretion of EPS, which likely served as protective barriers for cells against TCE toxicity.

This study examined the impact of Polystyrene microplastics (PS-MPs) on inflammation, apoptosis and autophagy within the liver, intestine, kidney, and gill of northern snakehead (Channa argus). In this study, 600 snakeheads (mean body weight: 10.5 ± 0.5 g) were randomly divided into four groups, each with three replicates. These groups were administered diets with incremental concentrations of PS (0 (CON), 500 (PS500), 1000 (PS1000), and 2000 ng/L (PS2000)) over a duration of four weeks. Histopathological analysis of the liver, intestine, kidney, and gill showed different degrees of pathological changes in the PS-added groups. Exposure to PS significantly increased ROS levels and elevated MDA content, while simultaneously reducing the activity of antioxidant enzymes (CAT, GSH, SOD, and GSH-PX) in these organs. The immune parameters (C3, C4, LYS, and IgM) in the liver, kidney, intestine, and gills of C. argus exposed to varying PS also changes. Additionally, increases in PS levels were accompanied by decreased expression of genes associated with antioxidant functions (cat, sod, gsh-px, nqo-1, ho-1, and gst). Analysis via quantitative real-time PCR (qRT-PCR) revealed changes in the mRNA levels of genes related to inflammation (tnf-α, il-8, nf-κb, jnk, il-1β, il-12, myd88, il-10 and iκbα), apoptosis (p53, bad, csa-9, cyt-c, bax, fas-2, and apaf-1), and autophagy (p62, atg5, lc-3, and beclin-1) in the liver, intestine, kidney, and gill. In summary, current research indicates that microplastics in water damage the antioxidant defense system, induce cell apoptosis, enhance inflammation, and lead to tissue damage. The adverse effects of microplastics on tissues may be due to TNF-α/ NF-κB/ Beclin-1 signaling pathways.

This research introduces an innovative full-process treatment technology that integrates dual-stage gas permeable membranes (GPM) and humic acid (HA) recovery to enhance Fenton oxidation of landfill leachate (LFL). In terms of full-process performance, this integrated approach (LFL-GPM-HA (Fenton)) synergistically combines LFL concentration, ammonia recovery, HA recovery, purified water reclamation, and efficient Fenton oxidation, thereby achieving holistic minimization, detoxification, and resource recovery of LFL. Specifically, under the conditions of low-intensity aeration and a temperature gradient of 65-55-25 °C, the GPM achieved an ammonia recovery rate exceeding 96 %, while the LFL was concentrated by a factor of 4.72 within 12 h. During HA recovery at pH 2, the HA yield from the concentrated LFL reached 3.68 g/L, representing an 88.72 % increase compared to the raw LFL. Due to the significant consumption of bicarbonate alkalinity during the GPM process, the required dosage of H₂SO₄ per gram of HA recovered was reduced by 86.72 %. Under different dimensionless oxidant dosages, the LFL-GPM-HA (Fenton) demonstrated a significant improvement in COD removal efficiency compared to standalone Fenton oxidation. In terms of dissolved organic matter (DOM) molecular-level transformation, ESI FT-ICR-MS analysis showed a significant enhancement in the removal of CHOS and CHONS in LFL-GPM-HA (Fenton), with a concurrent reduction in the produced sulfurous byproducts. Additionally, the LFL-GPM-HA (Fenton) notably increased the frequency of decarboxylation, desulfurization, and dealkylation reactions. In terms of operational stability and economic feasibility, this integrated system demonstrates excellent long-term stability and robust membrane fouling-cleaning recovery properties, achieving LFL treatment at a cost of approximately 12.142 $/m³, which is significantly more cost-effective than conventional full-process advanced treatment technologies (20-30 $/m³). In conclusion, the findings offer a pathway for developing more efficient and cost-effective strategies for LFL management.

This research evaluated the efficacy of self-sustaining alkalinity driven gas permeable membrane (SSAD-GPM) in ammonia recovery under low-rate aeration. This research initially confirmed the role of HCO3- and CO32- in enhancing alkalinity release and ammonia conversion. It was determined that providing alkalinity through HCO3- necessitates the consumption of inorganic carbon (IC), and highlighting the criticality of maintaining a HCO3-/NH4+ ratio exceeding 1.0 to optimize ammonia removal efficiency (>90.5 %). Alkalinity via CO32- involves a two-stage hydrolysis process, consuming IC only in the second phase. Then, comparing SSAD-GPM with alkalinity addition driven GPM (AAD-GPM) for real anaerobic digestate treatment, SSAD-GPM demonstrated an initial ammonia removal efficiency of 99.1 %, which reduced to 82.8 % after 40 days of operation. In contrast, the efficiency of AAD-GPM decreased to 62.6 %. Superior anti-fouling performance of SSAD-GPM, due to aeration-induced turbulence, mitigated concentration polarization and fouling. Efficiency was restored to 98.1 % post-cleaning with tap water. Lastly, this research assessed the alkalinity consumption and cost of various ammonia removal/recovery strategies, demonstrating that SSAD-GPM can substantially lower operating costs, yielding a net profit of $0.081/kg N. These findings underscore the potential of SSAD-GPM as a cost-effective approach for treating high ammonia-nitrogen wastewater with sufficient self-sustaining alkalinity (HCO3-/NH4+ > 1.0).

Crotonaldehyde wastewater is a typical high-concentration aldehyde-containing wastewater in the petrochemical industry, which adversely affect the metabolic functions of anaerobic microorganisms. This study assessed the influence of activated carbons (ACs) of different material sources on the anaerobic treatment of crotonaldehyde wastewater and identified the crucial material characteristics of ACs. The results indicated that the specific methanogenic rates of anaerobic granular sludge (AGS) in the wood activated carbon (W-AC), coconut shell activated carbon (CS-AC), and coal activated carbon (C-AC) group were 11.47, 9.97, and 6.50 mL CH4/(g VSS & sdot;d), which were 3.28, 2.84, and 1.86 times that of the control group, respectively. The cumulative methane yield and aldehyde removal efficiency of the W-AC group were more than the other groups. The contents of carboxylic and phenolic groups in the W-AC were 1.46 and 1.30 times higher than those in the CS-AC, and 4.75 and 4.33 times higher than those in the C-AC. This endowed W-AC with a stronger redox capacity, especially electron exchange capacity, thereby leading to the improved electron transfer activity and the enhanced methanogenesis. In addition, the introduction of W-AC facilitated the formation of a spatial distribution structure consisting of AC/bacteria, bacteria/archaea, and archaea from the outside to the inside of AGS, thereby contributing to improving the abundance of methanogens. This study demonstrated that dosing AC was an efficient strategy to alleviate inhibitory effects and enhance methane production during the anaerobic treatment of crotonaldehyde wastewater, and the results could be referred to for the treatment of wastewater containing aldehyde pollutants.

The potential of microbial fuel cells (MFCs) based biosensors for water monitoring and early warning is widely recognized. However, the electrochemically active biofilms (EABs) are typically obtained under anaerobic conditions and the formation requires a lengthy time span, which critically limits the application and advancement of the MFCs based monitoring technology. To accelerate the formation rate of EABs and thus shorten the establishment time of MFCs to better meet the needs for early warning and detection of pollutants in the actual aerobic water environment, the aerobic sludge was employed as an inoculation source to construct the MFCs sensing system in this study. It was revealed that biofilms with stable electrochemical properties could be promptly formed within 35h, reaching a level far ahead of previous studies. Moreover, toxicity tests for copper (Cu2+) ions at concentrations of 1mg/L, 10mg/L, and 50mg/L demonstrated outstanding performance with the maximum inhibition rates of 19.99%, 46.65%, and 53.02% respectively. Remarkably, the response time was found to decrease significantly with the increase of copper ion concentrations. Our results thus open up a new avenue for achieving rapid start-up of MFCs in aerobic conditions, which facilitates the applicability of MFCs based biosensing technology.

This study rigorously assessed the efficacy of gas-permeable membrane (GPM) technologies in recovering ammonia from landfill leachate, focusing on polypropylene (PP) and expanded polytetrafluoroethylene (ePTFE) membranes within in-situ (INS) and shell-tube (ST) configurations. The research spanned an array of determinants, including influencing factors, sustained operational efficiency, fouling dynamics, and recovery product purity. It was established that the INS-ePTFE configuration demonstrated formidable recovery capabilities and durable performance after fouling cleaning, with ammonia removal efficiency resurging to its initial state and stabilizing at 93 % post-maintenance. In contrast, the ST-PP configuration experienced an unrecoverable drop in removal efficiency to 83 %. Fouling analysis indicated that ePTFE membranes retained structural stability against organic and inorganic deposition, with humic substances and metal carbonates as predominant constituents. Conversely, PP membranes exhibited a decline in hydrophobic properties and structural integrity upon contamination. Furthermore, pH elevation significantly enhanced ammonia nitrogen mass transfer coefficients without increasing osmotic water transfer in INS systems. The INS system also showed promise for synergistic phosphorus recovery within the pH of 9 to 10. Then, NO3-, SO42- and humic acid did not impede ammonia translocation, whereas a 1.5 % mass fraction of Ca2+ incurred a roughly 30 % reduction in ammonia mass transfer coefficients across each system. The recovery of high purity (NH4)2SO4 attested to the exceptional retention capabilities of GPMs for organics and ions, with rejection rates surpassing 99.6 %. The comprehensive analysis underscored the operational superiority of the INS-ePTFE configuration in ammonia recovery.

In this study, the potential of a highly efficient composite of activated carbon with iron oxide active substances was explored for removing organic matters from reverse osmosis concentrate. The water quality characteristics indicated that the organic matters were mainly small molecular with molecular weight less than 1 kDa, and composed of hydrophilic-alkali, hydrophilic-neutral and hydrophobic-neutral substances. The specific surface area of the activated carbon composite was 482.96 m2/g, with 91.97% of the total specific surface area being microporous. Iron oxide active substances was loaded on activated carbon skeletons, mainly forming Fe2O3 and Fe3O4. The adsorption process was fitted with pseudo-second-order and Langmuir isotherm models, with the active site playing an important role in the adsorption capacity and the adsorption was spontaneous and endothermic. Combined with the refractory characteristics of the wastewater quality, electrostatic interactions, hydrogen bonding and functional group complexation were the main forces involved in the adsorption process, taking into account the refractory nature of the wastewater.

Microplastics have become ubiquitous in the environment due to the uncontrolled usage of plastic products. During their migration, microorganisms colonize their surface, forming what is known as plastisphere. The presence of human pathogenic bacteria on the plastisphere presents new opportunities for the spread of diseases during its extensive migration. Additionally, the plastisphere has been found to adsorb significant amounts of antibiotics from the environment, serving as a breeding ground for antibiotic resistance genes, posing significant risks to global antimicrobial medicine. Furthermore, plastisphere has the capability to adsorb heavy metals and co-select for co-resistance to antibiotics and heavy metals, exacerbating the complexity and persistence of antibacterial genes. Finally, various emerging pollutants, prevalent in the environment, may enhance the diversity and abundance of antibiotic resistance genes. Nevertheless, research on the genetic mechanisms, transmission properties, and environmental risks of co-resistance to antibiotics and heavy metals in microplastics is still in its infancy and requires comprehensive exploration.

The study developed a cost-effective integrated technology to treat swine wastewater at the pilot-scale small pigsty. The swine wastewater, which was separated rinse water after flowing through the slatted floor and the innovatively constructed liquid-liquid separate collection device, was subsequently pumped into an anaerobic baffled reactor (ABR) and then through zoning constructed wetlands (CWs) comprised of CW1, CW2, and CW3. The liquid-liquid separate collection device effectively reduced COD, NH4-N, and TN by 57.82%, 52.39%, and 50.95%, respectively. The CW1 and CW2 enhanced TN removal and nitrification, respectively, through rapid adsorption-bioregeneration of zeolite. Moreover, rice straws were used as solid carbon sources in CW3 to successfully promote denitrification at 16.0 g/(m3·d). The integrated technology (slatted floor-liquid liquid separate collection-ABR-CWs) reduced COD, NH4-N, and TN by 98.17%, 87.22%, and 87.88%, respectively, at approximately 10 °C. Microbial analysis results confirmed that the CWs exhibited apparent functional zoning, with denitrifiers dominating in CW3, nitrifiers dominating in the zeolite layers of CW1 and CW2, and denitrifiers dominating in the brick slag layers of CWs. This cost-effective integrated technology demonstrated significant potential for treating swine wastewater at low temperatures.

三氯乙烯(TCE)是石化废水中典型的有机污染物,对微生物具有极强的毒性.通过对挥发性脂肪酸批次试验进行生物测定,探讨TCE对厌氧水解酸化菌的产酸抑制作用,在TCE作用下水解酸化菌的胞外聚合物(EPS)和污泥zeta电位的变化以及TCE的去除特性.结果表明:TCE浓度为75 mg/L(半抑制浓度,EC50)时,对水解酸化菌的产酸量有抑制作用;随着TCE浓度升高,水解酸化菌的EPS中蛋白质浓度先增大后减少,其中TCE浓度为50 mg/L时EPS中蛋白质浓度达到最大值,为(33.94±0.25)mg/L;zeta电位的结果显示,污泥的凝聚性能随TCE浓度增大(0～100 mg/L)而增大;厌氧水解酸化菌对TCE的脱氯能力随TCE浓度的升高而降低,水解酸化菌转化TCE的脱氯率由TCE浓度为10 mg/L时的77.83％降为200 mg/L时的6.67％.TCE对水解酸化菌具有强烈的抑制作用,TCE主要是通过抑制细胞的蛋白质合成来抑制微生物活性,进而限制水解酸化菌降解TCE的能力.

This review aims to provide a comprehensive understanding of the potential of CMs-dominated DIET in the degradation of recalcitrant organic pollutants in AD. The review covers the mechanisms and efficiencies of recalcitrant organic pollutant degradation by CMs-dominated DIET, the comparison of degradation pathways between DIET and chemical treatment, recent insights on DIET-enhanced degradation, and the evaluation of the potential and future development of CMs-dominated DIET. The review emphasizes the importance of coupled syntrophic microorganisms, electron flux, and physicochemical properties of CMs in enhancing the degradation performance of AD. Additionally, it highlights the advantages of DIET-led syntrophic metabolism over traditional oxidation technologies in terms of environmental friendliness and efficiency. Finally, the review acknowledges the potential risks associated with introducing CMs into AD systems and provides guidance for waste treatment and energy recovery.

Crotonaldehyde is typical inhibitory compound of wastewater discharged in the petrochemical industry. To resolve the inhibition of crotonaldehyde on microorganism, electron donors (cellose, glucose and ethanol) were dosed to accelerate the biodegradation of crotonaldehyde by semi-continuous operation experiments. The results indicated that crotonyl alcohol was the most dominant biodegradable product of crotonaldehyde, and its conversion rates dosing ethanol, glucose and cellose as electron donors (2000 mgCOD/L) were 1.84, 1.46 and 1.21 times higher than that in control test when the initial concentrations of crotonaldehyde was 500 mg/L, respectively. Furthermore, the ethanol as electron donor was superior to cellose and glucose in relieving the inhibition of crotonaldehyde on the processes of acidogenesis, acetogenesis, and methanogenesis duo to the more electron release, faster electron transfer efficiency, less electron competition. Last, the enrichment of electroactive bacteria such as Syntrophobacter, Geobacter and the bacteria associated with reverse beta-oxidation pathway (RBO) such as Clostridium_sensu_stricto_12 also proved that higher electron transfer system (ETS) activity was obtained in the reactor dosed ethanol as electron donor. This study suggests that dosing electron donors is an efficient strategy to accelerate the biodegradation of crotonaldehyde, and the results could be referred to pretreat wastewater containing aldehyde pollutants.

Direct interspecies electron transfer (DIET) stimulated by conductive materials (CMs) enables intercellular metabolic coupling that can address the unfavorable thermodynamical dilemma inherent in anaerobic digestion (AD). Although the DIET mechanism and stimulation have been extensively summarized, the methanogenesis contribution, characterization techniques, and downstream processes of CMs-led DIET in AD are surprisingly under-reviewed. Therefore, this review aimed to address these gaps. First, the contribution of CMs-led DIET to methanogenesis was re-evaluated by comparing the effect of various factors, including volatile fatty acids, free ammonia, and functional enzymes. It was revealed that AD systems are usually intricate and cannot allow the methanogenesis stimulation to be singularly attributed to the establishment of DIET. Additionally, considerable attention has been attached to the characterization of DIET occurrence, involving species identification, gene expression, electrical properties, cellular features, and syntrophic metabolism, suggesting the significance of accurate characterization methods for identifying the syntrophic metabolism interactions. Moreover, the type of CMs has a significant impact on AD downstream processes involving biogas purity, sludge dewaterability, and biosolids management. Finally, the central bottleneck consists in building a mathematical model of DIET to explain the mechanism of DIET in a deeper level from kinetics and thermodynamics.

采用BioWin5.3 软件对某石化园区综合污水处理厂进行模拟,以 3～6 月的水质数据搭建生物处理段的稳态模型,通过对关键参数氨氧化细菌最大比增长速率μA、普通异养菌好氧产率系数YH和普通异养菌最大比增长速率(μH)进行测定(分别为 0.7475 d-1,0.717 g/g(以COD计)和 2.9975 d-1),将其代入模型,并用 9 月水质数据进行验证,模型模拟出水的相对误差小于 10%.利用验证后的模拟方法,考察巴豆醛废水排入对综合污水处理厂运行的影响,发现即使综合废水与巴豆醛废水混合体积比为 2000∶1,模拟出水COD质量浓度仍高达 102 mg/L,即巴豆醛废水在预处理设施检修等不利情况下,也不能排入综合污水处理厂.