Coke powder（CP）, a coking byproduct, was employed as an adsorbent to investigate the adsorption performance and mechanisms toward polycyclic aromatic hydrocarbons（PAHs）substituted with different functional groups—naphthalene, naphthol, and naphthoic acid. The potential of CP for removing PAHs from wastewater was further evaluated through systematic analyses. Adsorption performance tests demonstrated removal efficiencies of 97.4%, 86.6%, and 76.8% for naphthalene, naphthol, and naphthoic acid, respectively, within 120 min, with pseudo-second-order kinetic rate constants of 0.680, 0.532, and 0.183g/（mg⋅min）. The maximum adsorption capacities followed the order: naphthalene（23.8mg/g）>naphthol（8.04mg/g）>naphthoic acid（3.94 mg/g）. While pH exhibited minimal effects on the adsorption of naphthalene and naphthol, naphthoic acid adsorption was significantly enhanced under acidic conditions compared to neutral or alkaline environments. Results of FTIR, XPS, DRUV-Vis spectroscopy, and DFT calculation revealed that the adsorption of naphthalene on CP was multilayered, primarily driven by hydrophobic interactions, van der Waals forces, and π-π electron donor-acceptor（EDA）interactions. In contrast, the adsorption of naphthol and naphthoic acid involved monolayer chemisorption, attributed to strong π donors and the π-π EDA interactions with the polarized electron-depleted regions on the CP surface. The hydrophilic nature of the hydroxyl group in naphthol reduced the saturation adsorption capacity. While electrostatic repulsion between naphthoic acid and CP weakened the π-π EDA interaction, resulting in a slightly lower adsorption capacity.

A laboratory-scale AnMBR was established to investigate the methanogenic performance, organic matter removal efficiency, membrane fouling behavior, as well as the material flow and energy conservation and emission reduction under the optimal operating conditions during the treatment of methylamine wastewater. The results showed that as hydraulic retention time（HRT）decreased from 36h to 8h, average methane yield rose from 0.231L CH₄/g COD to 0.287L CH₄/g COD. COD removal was stable above 95%, methylamine removal hit 100%. But at 6h HRT, methylamine removal was only 44.3%, reactor performance dropped, and methane yield fell to 0.094L CH₄/g COD. Membrane flux rose from 1LMH to 6LMH, transmembrane pressure（TMP）growth was slow. At 12h HRT, long operation made TMP exceed 20kPa. After replacing the membrane module, analysis show irreversible fouling inside, relate to microbial extracellular polymers. Considering comprehensively the methanogenic performance and the growth rate of TMP in each stage, the optimal operating condition is determined as HRT=8h. More than 80% of the influent COD is converted into methane, the generated bioenergy is significantly higher than the power consumption of the system operation, the net energy potential reaches 4.142kW·h/m³, and it can reduce carbon emissions by 2.239kg CO₂/m³.

Employed a SBR to simulate municipal wastewater as the influent matrix and initiated the Nitritation-Enhanced Partial Denitrification-Complete Autotrophic Nitrogen Removal Over Nitrite（N-EPD-CANON）process. The anoxic duration within the EPD system was meticulously adjusted to scrutinize the impact on endogenous nitrite accumulation and the consequent performance alterations within the CANON system. The objective was to elucidate the influence of anoxic time on endogenous nitrite concentration and its subsequent effects on nitrogen removal efficiency, the activity of functional microbial groups, and the structure of microbial communities within the CANON process. The findings revealed that an anoxic duration of 40minutes within the EPD system was optimal for capturing influent organic matter while concurrently promoting the endogenous nitrite to accumulate at a favorable concentration of approximately 4mg/L. Under sustained operational conditions, the CANON reactor achieved a total nitrogen removal rate of 86.43%. The specific anammox activity（SAA）was determined to be 0.82gN/（gVSS·d）, the particular nitrate production rate（SNPR）was reduced to 0.28gN/（gVSS·d）, and the specific ammonium removal rate（SAOR）was recorded at 0.70gN/（g VSS·d）. Additionally, the application of 3D-EEM and PARAFAC techniques to analyze the fluorescence components of EPS in the sludge indicated that the intensification of endogenous nitrite had a beneficial effect on increasing the content of aromatic proteins within the EPS without altering its composition. Microbiota community analysis reveals that Candidatus_Competibacter is the dominant genus in the EPD system, accounting for 24.61%. In contrast, in the CANON system, the relative abundance of Nitrosomonas at 2.67% ensures the NO₂^--N supply for AnAOB, and Candidatus Brocadia, as the main genus of AnAOB, accounts for 13.34%.

The effects of three different influent strategies on the protein content of extracellular polymeric substances（EPS）were investigated to assess their impact on sludge retention capacity of the CANON process. R1was operated under conventional influent strategy as the control group, while R2 and R3 were subjected to different variable influent strategies. After 90 days of operation, the SVI values in R1, R2, and R3 were 62.93, 53.10, and 57.59mL/g respectively indicating that the variable influent strategies could improve sludge settleability. The PN/PS ratios were significantly higher in R2（8.21）and R3（7.61）compared to R1（5.56）. Three-dimensional fluorescence analysis revealed that the proportion of aromatic proteins in TB-EPS was highest in R2（32.47%）, much higher than in R1（11.58%）and R3（10.5%）. This indicated that the variable influent strategy promoted the formation of aromatic proteins in TB-EPS, enhancing the hydrophobicity of the sludge and improving settleability. The specific anaerobic ammonium oxidation activity（SAA）increased to 4.03, 4.68 and 4.36mg N/（g VSS· h）in R1, R2, and R3, respectively. Notably, the SAA in R2 and R3 exceeded that of the seed sludge, indicating the successful formation of mature CANON granular sludge. Although microbial activity in R2 and R3 was initially inhibited by loading fluctuations during early operation, the microbial communities gradually adapted to environmental fluctuations and regained stable metabolic activity, successfully operating the CANON process on day 54 and day 51, respectively. Total nitrogen removal efficiencies reached approximately 72.54%, 70.14%, and 73.75% in R1, R2 and R3 by day 90, demonstrating effective nitrogen removal performance.

A self-drive weak electric strengthening constructed wetland（SECW）, which was renovated from a hybrid subsurface constructed wetland（HCW）based on ANAMMOX, was established in this study, and its operational performance was thoroughly investigated. Further, the microbial characteristics in the system during the steady operational period were explored, and the nitrogen transformation pathways were also analyzed and elucidated. The results showed that, prefabrication of electroactive biofilms and appropriate layout of the electrodes not only simultaneously enhanced electrode-dependent ammonium oxidation and cathodic denitrification in the SECW, but also significantly increased the abundance and activity of anaerobic ammonium-oxidizing bacteria in its substrate layer. Consequently, a multi-path nitrogen removal system based on ANAMMOX was formed in the device, thereby significantly improving the nitrogen removal performance of the SECW. When the electrode configuration was adopted as “double cathode-single anode” and the hydraulic loading rate（HLR）was 0.08m³/（m²·d）, the SECW exhibited optimal performance. Specifically, its COD, TP, TN, and NH₄⁺-N removal rates could reach up to（91.39±3.09）%,（93.64±1.15）%,（91.67±2.77）%, and（94.34±2.72）%, respectively. Additionally, the mean output voltage and power density of the system respectively maintained at（816.45±8.44）mV and 651.96W/m³.

The scouring of sediment deposits in sewer system constitutes a critical factor in overflow pollution. By integrating rainfall intensity variations, stratified anti-scouring characteristics, and dynamic pollutant transport, a dynamic transport model was developed to evaluate stratified sediment scouring under different rainfall intensities and its impact on water quality transformation. Experimental results demonstrate significant disparities in sediment scouring efficacy across varying rainfall intensities. Under light rainfall conditions, the scouring rate measured 6.04m³/h, primarily removing superficial sediment layers. Moderate and heavy rainfall events induced substantial enhancement of flow shear forces, with pipe discharge reaching 71.08m³/h during intense precipitation, capable of mobilising larger particles from underlying sediment strata. A pronounced "initial phase effect" was observed across all rainfall intensities, characterised by rapid pollutant concentration peaking during precipitation onset. Under heavy rainfall, sulphate concentrations surged to 17.89mg/L within 1min before stabilising at 8.95mg/L, while Total Chemical Oxygen Demand（TCOD）exhibited a swift ascent to 2106.3mg/L followed by stabilisation at 1056.6mg/L. In contrast, light rainfall conditions yielded markedly lower peak values of 10.29mg/L for SO₄^2- and 1100.60mg/L for TCOD, though similarly demonstrating rapid initial concentration escalation followed by gradual stabilisation.

This research conducted an experiment on DNAPL contamination in a saturated porous medium within a three-dimensional sandbox and performed synchronized dynamic monitoring using electrical resistivity tomography（ERT）. The resistivity images obtained from ERT were used to determine the spatial distribution of DNAPL contaminants, which were then compared with the numerical simulation model established in the sandbox experiment. The absolute value of the relative error in the diameter of the DNAPL distribution area obtained from the numerical simulation and the DNAPL distribution area determined by the ERT monitoring ranged from 2.00% to 27.50% across different spatial locations. The absolute value of the relative error in the diameter of the DNAPL distribution area obtained from the numerical simulation and the DNAPL distribution area determined by the ERT monitoring ranged from 2.7% to 40.58% at different time points. The results demonstrate the feasibility of using the numerical simulation software Petrasim to predict the distribution range of DNAPL contamination in saturated sandy soil.

A total of 78 water samples from mesotrophic and eutrophic urban lakes in Nanjing, Jiangsu Province, China were systematically analysed using three-dimensional excitation-emission matrix（EEM）fluorescence spectroscopy coupled with parallel factor analysis（PARAFAC）to characterize dissolved organic matter（DOM）composition and sources as well as their links with water physiochemistry parameters. This study was designed to unravel the effects of eutrophication on the fluorescence characteristics of DOM and its influence pathway. Three distinct fluorescent components were identified: anthropogenic-derived humic-like substances（C1）, terrestrial humic-like substances（C2）, and microbial-produced protein-like substances（C3）. Eutrophic urban lakes exhibited significantly higher fluorescence intensities in both C2 and C3 relative to mesotrophic urban lakes. Fluorescence indices confirmed dual DOM sources-terrestrial inputs and autochthonous production. Meanwhile, although the humification index of DOM in mesotrophic urban lakes exceeded that in eutrophic urban lakes, the humification index of DOM was below 1.0 for all samples. Moreover, the biological index of DOM exhibited an increasing trend with the elevation of trophic status of water column. Additionally, significantly elevated Chla concentration were observed in eutrophic lakes compared to mesotrophic lakes. Strong positive correlations were identified between Chla concentration and the fluorescence intensity of C2 and C3 components alongside the biological index of DOM, suggesting that eutrophication may induced autochthonous DOM by stimulating algae reproduction.

The determination of environmental background values for groundwater was recognized as a prerequisite and key step for the scientific identification, evaluation, and prevention of groundwater pollution. In this paper, the development history of groundwater environmental background value research was reviewed both domestically and internationally. Existing calculation methods for groundwater environmental background values were discussed along with their respective advantages and disadvantages. The research paradigm for background value reasonableness validation analysis and cause analysis was systematically summarized. Finally, existing problems in current groundwater environmental background value research were identified, and future development trends were projected. It was observed that inconsistencies in naming and definitions of groundwater environmental background values persisted among scholars worldwide. Although the influence of human activities on groundwater chemical components had been considered, quantitative determination of the "low human activity impact" threshold in conceptual frameworks remained challenging. Methods for determining environmental background values were generally categorized into mathematical-statistical approaches, model-based methodologies, and other alternative techniques. Each method was found to possess distinct advantages and limitations. The combination of hydrochemical analysis with mathematical statistics was demonstrated to emerge as one of the representative integrated approaches for calculating groundwater environmental background values, though methodologies for trace and micro-component analysis were noted to require further development. The reasonableness of environmental background values was typically assessed through comprehensive evaluation of multiple factors including surrounding pollution sources, hydrogeological conditions, lithological characteristics, land use patterns, pollution percentage indices, and stable isotope results. Regional geological settings and hydrogeological conditions were identified as primary controllers of groundwater environmental background values, while biogeochemical processes were determined to dominate micro-enrichment mechanisms. Based on established environmental background values, groundwater pollution levels were effectively evaluated, pollution risk areas were scientifically delineated, and reference thresholds were provided for environmental regulation and remediation targets. Future priorities were emphasized to include the urgent establishment of a global groundwater environmental background value database, enhanced application of existing background value data, and strategic utilization of big data analytics. These measures were proposed to optimize global groundwater resource protection and pollution control strategies under combined pressures of climate change and anthropogenic impacts.

The discovery of complete ammonia-oxidizing bacteria（comammox）provided a novel direction for improving nitrification efficiency in wastewater treatment systems. The potential of their metabolic pathways and functional genes for efficient nitrogen an d carbon removal from wastewater was demonstrated. However, strategies to achieve robust comammox enrichment remained controversial. Further investigations were required to characterize the specific contributions to ammonia removal and nitrous oxide（N₂O）production during the nitrification process. The technical strategies for efficient comammox enrichment and the impacts of key factors including environmental substrate concentration, dissolved oxygen, operational processes, and temperature on the selective enrichment of comammox were summarized. Chlorate was employed as a specific inhibitor targeting comammox in combination with 1-octyne to construct a dual-inhibitor experimental system, which was capable of clarifying the nitrification contribution and N₂O emission potential of comammox in wastewater treatment systems.