Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202506041
Urban and rural multi-source organic waste faces bottlenecks including high compositional heterogeneity, single resource recovery pathways, and uneven product quality. In the Taihu Lake region, active tourism and catering, high greening, and dense water networks generate large volumes of diverse waste with high moisture content, exacerbating these issues. This study evaluated a coupled bio-drying and aerobic composting process at a demonstration center in Linhu Town, Suzhou, Jiangsu Province, employing a three-stage control strategy: gradient dewatering, high-temperature stabilization, and maturation enhancement. Continuous operation showed that kitchen waste moisture content decreased from 77.70% to 58.69% after 1 day of bio-drying, to 23.22% after 7 days of silo reactor composting, and to 17.70% after at least 20 days of maturation. The aerobic composting phase maintained temperatures above 55°C for over 5 days, reaching a maximum of 68.1°C, meeting the harmless treatment requirements of CJJ 52—2014. After 20 days of maturation, the organic fertilizer product had an electrical conductivity below 4.00 mS·cm−1, organic matter content of 51.22%, total nutrient content of 5.61%, and heavy metal concentrations below the limits of NY/T 525—2021. The results provide technical support for efficient treatment and resource utilization of urban and rural organic waste.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202604017
The Shule River Basin, a typical arid inland river basin, faces critical water scarcity that threatens ecological security and sustainable development. This study integrated the FLUS and InVEST models to simulate water yield in 2030 and 2050 under three climate scenarios (SSP119, SSP245, SSP585). Geographic detectors quantified the driving mechanisms of natural and human factors. Results showed: (1) Desert dominates land use (78.6% in 2020). Under SSP119, desert area decreases by 0.69% by 2050, while under SSP585 it expands by 5.7%, with grassland loss of 23.0%, indicating severe ecological degradation. (2) Water yield exhibits a south-high, north-low spatial pattern, with high values in glacier-covered and high-altitude areas. SSP119 yields the most significant increase (147.6×10^8 t by 2050), whereas SSP585 shows minimal increase (43.9×10^8 t) due to extreme climate. (3) Precipitation and DEM are core driving factors; the interaction between land use type and precipitation has the strongest influence, implying that artificial land use changes can significantly regulate water yield. This multi-scenario framework provides decision support for water resource management and ecological governance in arid inland river basins.
The Chinese Journal of Process Engineering•2026•DOI: 10.12034/j.issn.1009-606X.225185
Sulfur hexafluoride (SF6), widely used as an insulating gas in high-voltage electrical equipment, possesses a global warming potential (GWP) 25,200 times that of CO2, necessitating efficient degradation technologies. This study employed computational fluid dynamics (CFD) to simulate the thermal catalytic degradation of SF6 in a fixed-bed reactor, integrating models for porous media, heat transfer, turbulence, and chemical kinetics. The simulations revealed significant radial non-uniformities in pressure, velocity, temperature, and species concentration distributions, with temperature identified as the dominant factor influencing degradation efficiency. Radial temperature gradients caused uneven reaction rates, with degradation rates near the wall substantially exceeding those at the central axis, thereby reducing overall SF6 conversion. To address this, structural optimizations were implemented, including reducing the reactor tube diameter and incorporating inert porous media with high thermal conductivity at both ends of the catalytic section. These modifications enhanced radial heat transfer, homogenized the temperature field, and improved the uniformity of reaction rates and species concentrations. Parametric studies on inlet gas velocity showed that both excessively low and high flow rates were detrimental: low velocities led to underutilization of the downstream catalyst and increased energy consumption, while high velocities deteriorated heat transfer and exacerbated radial temperature gradients. The optimal inlet velocity range was determined to be 0.4–0.8 m/s for a reactor tube inner diameter of 10 mm, balancing catalyst utilization, energy consumption, and degradation efficiency. This research provides data-driven guidance for the design and scale-up of SF6 catalytic degradation reactors.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202509001
To address low nitrogen removal efficiency in wastewater treatment plant (WWTP) effluent due to insufficient carbon sources and weak reoxygenation in conventional constructed wetlands (CWs), a tidal flow-subsurface flow integrated CW using iron-loaded biochar (BC-TF) as substrate was developed, with zeolite-based CW as control. Simulated wastewater experiments, water quality monitoring, nitrification/denitrification intensity assays, and high-throughput sequencing were employed. Results showed that tidal flow operation significantly enhanced removal of total nitrogen (TN) and ammonia nitrogen (NH4+-N), and increased nitrification intensity. Addition of iron-loaded biochar significantly improved TN and nitrate nitrogen (NO3−-N) removal, with BC-TF achieving an average TN removal of 86.03%, significantly higher than other groups (P<0.001). Microbial analysis revealed Proteobacteria, Actinobacteria, and Bacteroidetes as key phyla; iron-loaded biochar increased microbial abundance and diversity in tidal flow wetlands, while tidal flow alone reduced bacterial diversity. Pilot-scale experiments confirmed that tidal flow increased dissolved oxygen and nitrogen removal. This study is the first to combine iron-loaded biochar with tidal flow-subsurface flow CWs, systematically revealing the synergistic nitrogen removal mechanism of 'iron-loaded biochar-tidal flow-microorganisms', clarifying the role of iron-nitrogen coupling, and validating engineering applicability via pilot tests. The combination enhances reoxygenation, supplements carbon sources, and optimizes microbial community structure, effectively improving deep nitrogen purification of WWTP effluent, providing technical reference for tailwater treatment.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4163-y
Liquid metals (LMs) are promising catalyst systems due to their unique interfacial properties, yet migration and aggregation of active species cause performance degradation. Here, we report a composition optimization strategy using a Ga-In eutectic liquid metal support to reduce surface energy and achieve homogeneous incorporation of Cu species (GaIn-Cu). Comprehensive characterizations confirm uniform Cu dispersion, which inhibits migration and formation of CuGa2 intermetallic phases during CO2 electroreduction (CO2RR). The GaIn-10-Cu catalyst achieves a maximum CH4 Faradaic efficiency of 73.49% at -0.8 V vs. RHE, significantly higher than Ga-Cu (61.49%). Moreover, GaIn-10-Cu exhibits enhanced stability for CH4 generation over 40 h of continuous operation. In-situ spectroscopic studies reveal that GaIn-10-Cu favors formation and protonation of key *CHO and *OCH3 intermediates, steering selectivity toward CH4. This work demonstrates that tuning LM composition modulates catalytic site performance, offering a strategy for durable and selective LM-based electrocatalysts.