Ozonation is an effective advanced treatment technology for textile dyeing and finishing wastewater； however， its large-scale application is primarily constrained by its intrinsically low ozone mass transfer efficiency. Membrane contactor reactors （MCRs） can significantly enhance ozone mass transfer by constructing microscale gas-liquid interfaces， offering advantages such as high mass transfer efficiency and the absence of secondary pollution. Nevertheless， issues including membrane fouling， high material costs， and poor operational stability still limit their engineering-scale implementation. This study systematically reviewed recent advances in the mechanisms of ozone mass transfer enhancement in MCRs. The principles of gas-liquid interfacial mass transfer and the design characteristics of hollow fiber membrane contactor configurations were introduced. The regulatory effects of membrane material properties （e.g.， the selection of hydrophobic PTFE/PVDF）， operating parameters （gas-liquid flow rates， transmembrane pressure， and pH）， and mass transfer models on the volumetric ozone mass transfer coefficient were critically analyzed. Furthermore， the application efficiency of MCRs in textile dyeing and finishing wastewater treatment was evaluated， with particular emphasis on efficient dye removal， organic matter mineralization， and decolorization. Research demonstrated that optimized MCR systems could increase the volumetric ozone mass transfer coefficient by 5~10 times compared with conventional bubble column processes， thereby substantially enhancing the kinetics of pollutant degradation. However， challenges such as membrane fouling-induced flux decline， bromate by-product formation， and cost-benefit optimization remained to be addressed. Finally， future research directions were proposed， focusing on the rational design of multifunctional composite membranes integrating antifouling properties， corrosion resistance， and low cost； the elucidation of interfacial reaction mechanisms through coupling with intensified fields such as high-gravity and electrocatalytic processes； the development of intelligent parameter regulation systems based on process modeling； and comprehensive techno-economic and environmental risk assessments at the pilot scale. These efforts will provide theoretical support and technical guidance for the engineering application of MCR-ozone processes.

The widespread use of tetracycline has resulted in elevated antibiotic concentrations in natural water bodies， posing significant threats to aquatic ecosystems and public health. Although iron-manganese modified biochar （IMBC） can effectively remove tetracycline， its powdered form is prone to leaching during application， leading to reduced utilization efficiency and potential system clogging. In this study， foam concrete （FC） was employed as an immobilization matrix to fabricate a novel iron-manganese modified biochar foam concrete （IMBC-FC） composite. The results showed that sufficient hydration reactions occurred during the immobilization process， endowing IMBC-FC with a highly porous structure that effectively avoided the masking of active sites on IMBC. The tetracycline removal efficiency of IMBC-FC reached 87.7%， and the impact of immobilization on the removal performance of IMBC was less than 10%. Removal pathway analysis indicated that oxidative degradation contributed approximately 56.9% to tetracycline removal， and singlet oxygen （¹O₂） was identified as the dominant reactive oxygen species （ROS） in the system. Functional groups such as hydroxyl （—OH） and carboxyl （—COO⁻） generated during hydration likely participated in both ROS generation and electron transfer， thus synergistically facilitating the degradation process. Furthermore， a comprehensive evaluation of the engineering application performance of IMBC-FC was carried out in accordance with relevant standards for water treatment filter media and constructed wetland substrates. The results demonstrated that IMBC-FC exhibits excellent advantages in porosity， mechanical strength， and tetracycline removal efficiency， indicating its promising engineering application prospects. This study is expected to provide a reliable technical pathway and theoretical support for the efficient immobilization of metal-modified biochar.

This study， conducted at the Haikou Jiangdong Water Plant， applied a direct ultrafiltration process to treat the Nandu River water for potable use. Pilot-scale experiments were performed to optimize key operational parameters， including filtration cycle， backwash regime， and chemical-enhanced backwash （CEB） dosing and frequency. Under the optimized condition， the study comprehensively evaluated treatment performance， membrane-fouling characteristics， and techno-economic outcomes. The results showed that with a filtration cycle of 90 min and a high-intensity， short-duration backwash regime （170 L/（m²·h） flux， 150 s air scouring， 10 s combined air-water top backwash， 10 s combined air-water bottom backwash）， together with CEB using 500 mg/L sodium hypochlorite at a frequency of 7 days， the system exhibited robust adaptability and stable performance across varying raw-water qualities. The system maintained regulatory-compliant effluent even when raw-water COD_Mn reached 7.01 mg/L during high-turbidity periods （≥50 NTU）. However， when raw-water COD_Mn approached 3.6 mg/L during low-turbidity periods （<50 NTU）， there was a potential risk of the effluent COD_Mn exceeding the applicable drinking-water standard. Over 42 days of operation， the transmembrane pressure increased by a cumulative 8.48 kPa but stabilized following a short-term high-turbidity perturbation. Membrane-fouling analyses confirmed that the optimized operating conditions effectively limited fouling and identified siliceous-aluminous inorganic residues as the primary irreversible foulant fraction. A techno-economic assessment indicated water production costs of RMB 0.226/m³ （low-turbidity） and RMB 0.243/m³ （high-turbidity）， both lower than the RMB 0.261/m³ estimated for a conventional coagulation-sedimentation-filtration-disinfection process. The operational-parameter framework established in this study provides experimental evidence and technical support for applying direct ultrafiltration as a primary pretreatment unit in engineering practice.

This study proposed a hybrid Long Short-Term Memory （LSTM）-Transformer model integrated with wavelet denoising for water quality prediction. Using hourly monitoring data （water temperature， turbidity， pH， conductivity， and dissolved oxygen） collected from two municipally controlled river cross-sections in South China from 2021 to 2024， the discrete wavelet transform was first applied for noise reduction. Subsequently， a predictive model combining LSTM and Transformer architectures was constructed. Experimental results demonstrated that the proposed model achieved outstanding performance in predicting dissolved oxygen （DO） concentrations for the next four hours at both sites （Site 1： coefficient of determination （R²）=0.8015， mean absolute error （MAE）=0.5169 mg/L， root mean square error （RMSE）=0.8494 mg/L； Site 2： R²=0.8873， MAE=0.4456 mg/L， RMSE=0.7143 mg/L）， significantly outperforming standalone LSTM and Transformer models （the R² of the proposed model increased by 5.7%， while MAE and RMSE decreased by 20.2% and 10.4%， respectively）.Furthermore， the SHAP interpretability method was employed for feature importance analysis and global impact interpretation， revealing that the key water quality factors influencing DO and their complex nonlinear relationships exhibited significant site-specific heterogeneity. This underscores the necessity of incorporating specific environmental contexts （e.g.， geographical features， hydrological conditions， and pollution source distribution） for mechanistic interpretation. The findings of this study provide an effective and interpretable technical reference for high-precision real-time prediction and intelligent management of regional river water quality.

Vivianite crystallization is recognized as an efficient and environmentally friendly approach for phosphorus recovery in wastewater resource utilization. However， in practical phosphorus recovery processes， the dissolved organic matter （DOM） present in the supernatant of sludge anaerobic fermentation may interfere with vivianite crystallization， thereby affecting both the phosphorus recovery efficiency and the product properties. In this study， polysaccharides， proteins， acetic acid， propionic acid， and humic substances were selected as representative organic matter to systematically assess how their types and concentrations affect vivianite crystallization， and to elucidate their impacts on crystal morphologies and structure as well as the associated interaction mechanisms. The results showed that the inhibitory effects of different types of organic matter on phosphorus recovery via vivianite crystallization followed the order of humic substances > proteins > propionic acid > acetic acid > polysaccharides. The presence of humic substances significantly reduced the phosphorus recovery rate and crystal size， and led to the formation of irregular surface deposits on the crystals. This study provides a theoretical foundation for clarifying the interference mechanism of DOM in vivianite crystallization within fermentation broth and offers insights for its regulation. These findings are of great importance for guiding the optimization of the efficient phosphorus recovery processes in real wastewater systems.

This study took a large municipal wastewater treatment plant （WWTP） in northern China as the research object， and systematically investigated the influence characteristics and response mechanism of abnormal influent shock load on the structure of activated sludge microbial community. The results showed that influent shock caused drastic changes in the structure of activated sludge microbial community： the abundances of core functional flora such as Proteobacteria and Bacteroidetes decreased significantly by 55.30% and 44.35%， respectively； the community diversity was reduced， the nitrification function was weakened， and the concentration of effluent ammonia nitrogen increased. Meanwhile， shock-resistant flora such as the genus SJA-28 within Chlorobi proliferated rapidly， showing a 5.68‑fold increase in relative abundance compared to the normal period， which helped sustain the pollutant removal capacity of the system to some extent. These findings confirmed that the activated sludge system has strong shock resistance and self-recovery capacity. The implementation of regulatory measures such as shortening sludge retention time （SRT） and increasing the dosage of sodium acetate and phosphorus removal chemicals was shown to be conducive to the rapid recovery of functional flora. Based on these findings， it is suggested that in practical operation， SRT adjustment strategies should be flexibly adjusted according to influent quality characteristics and temperature conditions， so as to improve the stability and resilience of the wastewater treatment system in responding to shock loading.

Iron-dependent autotrophic denitrification （IDAD） is a promising biological technology for nitrogen removal from wastewater with a low C/N ratio. While significant differences in community structure among IDAD consortia from different studies have been reported， the underlying reasons remain unclear. Hypothesizing that the anion type of ferrous salts could be a key contributing factor， this study enriched two IDAD consortia （R1 and R2） using FeCl₂ and FeSO₄ as respective electron donors under identical inoculum sludge conditions. Their nitrogen removal performance， extracellular polymeric substance （EPS） composition， iron oxidation product properties， microbial community structure， and functional gene distribution characteristics during long-term operation were systematically compared. The results showed that R1 exhibited higher denitrification efficiency and Fe（Ⅱ） oxidation activity. Key iron-oxidizing bacterial genera such as Gallionella showed a significantly higher relative abundance in R1 than in R2， and R1 also maintained higher community diversity. Metagenomic analysis further revealed a higher abundance of functional genes related to iron oxidation and denitrification in R1. In contrast， R2 was enriched with more genera associated with sulfate metabolism and complex organic matter degradation. Distinct differences were also observed in EPS composition and iron mineral surface properties between the two consortia. This study confirms that the type of ferrous salt significantly regulates the structural assembly and metabolic functions of IDAD consortia， providing a theoretical basis for optimizing their application in practical wastewater treatment.

Against the backdrop of increasingly severe global sustainability challenges， Bipolar Membrane Electrodialysis （BMED） technology is emerging as a pivotal solution driving transformation in the chemical， environmental， and resource management sectors. This technology not only demonstrates remarkable efficiency and economic benefits in critical areas such as resource extraction， pollution control， and CO₂ capture but also exhibits substantial potential for large-scale commercial implementation. This review systematically outlines the working principles and fabrication methods of bipolar membranes， along with their applications across various industrial fields， highlighting their significant capacity to advance greener and more efficient industrial processes. Representative case studies in resource recovery， pollution mitigation， and CO₂ capture are presented to illustrate the promising industrial prospects of BMED and validate its practical value in enabling sustainable resource utilization and environmental protection.

Under the context of global warming， it is imperative to advance the synergistic efficiency of pollution reduction and carbon mitigation in the wastewater treatment industry. This study is based on the 2023 operational data from three typical municipal wastewater treatment plants （WWTPs） in Jiangsu Province employing A²/O and its modified processes. Using the emission factor method， carbon emission accounting and characteristic analysis were conducted. and explored the impact of influent characteristics and operational parameters on the carbon emissions of WWTPs through path analysis. From an indirect control perspective， this study assessed the carbon reduction potential of measures such as photovoltaic power generation and water-source heat pumps. The results indicate that： The total carbon emission intensity of the three typical WWTPs ranged from 0.578 kg/m³ to 0.671 kg/m³， with total carbon emissions between 18890 t and 28150 t. The indirect carbon emissions account for a relatively high proportion （71.7%） of the total carbon emissions in A²/O wastewater treatment plant， with electricity consumption contributing the most （53.3%） to the carbon emissions. The carbon emissions attributed to carbon source dosage accounted for the largest proportion of chemical consumption， reaching 36.9% to 59.5% of the total chemical carbon emissions. The operation of wastewater treatment plants with lower influent concentrations requires higher energy and material consumption， resulting in greater indirect carbon emissions. Furthermore， the influent water quality characteristics and operational parameters of typical A²/O process wastewater treatment plants all have direct or indirect impacts on various types of carbon emission intensities. To effectively control carbon emissions， plants can actively optimize process operational parameter adjustments， implement equipment upgrades and retrofits， adopt intelligent/smart control systems， and implement various carbon-alternative measures. By adopting PV power generation and water-source heat pumps， WWTP2 could theoretically achieve 22.7% and 100.2% carbon displacement rates， respectively， demonstrating significant carbon reduction potential.

Per- and polyfluoroalkyl substances （PFASs） are frequently detected at elevated concentrations in water bodies of the lower Yangtze River， posing risks to drinking water safety and human health. This study investigated the occurrence of 23 typical PFASs in source water， treated water， and tap water from eight drinking water treatment plants （DWTPs） in the lower reaches of the Yangtze River. The removal efficiency of PFASs by the treatment processes and their priority for control were also assessed. The results revealed the presence of 19 PFASs across the eight DWTPs， with total concentrations ranging from 32.02 to 167.68 ng/L and an average of 85.86 ng/L. Among these， 14 long-chain and 5 short-chain PFASs were identified， contributing 35.7% and 64.3% to the total concentration， respectively， indicating that short-chain PFASs were the predominant pollutants. The major contaminant monomers were perfluorooctanoic acid （PFOA）， perfluorobutanoic acid （PFBA）， perfluorobutanesulfonic acid （PFBS）， and perfluorohexanoic acid （PFHxA）. The overall removal efficiency of PFASs by the drinking water treatment processes was 17.8%， with a removal efficiency of 22.2% for long-chain and 15.1% for short-chain congeners. Notably， concentrations of 14 PFASs increased during distribution from the treatment plant to the tap， resulting in an overall rebound rate of 39.6%. PFBA， PFOA， and PFBS were the primary contributors， accounting for over 92.8% of this concentration increase. Modeling assessment identified PFOA， perfluorononanoic acid （PFNA）， perfluorododecanoic acid （PFDoA）， and perfluorooctanesulfonic acid （PFOS） as priority PFASs requiring enhanced monitoring and control measures.