Search Results (7,744)

With the expansion of global oil and gas resource exploration and development into deep and ultra deep layers, the efficient development of deep carbonate rock fracture cave reservoirs has become the key to ensuring energy security. However, this type of reservoir commonly faces high temperatures, high salinity, and extremely strong heterogeneity, leading to increasingly severe water content spikes caused by dominant water flow channels. Although the existing traditional inorganic plugging agent has good temperature resistance, it has the defects of great brittleness and easy cracking, while the organic polymer gel is prone to degradation failure under high temperature and high salt environments. In order to solve the above problems, a new biochar-enhanced inorganic composite gel system was constructed by using biochar prepared from agricultural and forestry waste pyrolysis as a functional enhancement component. Through rheological testing, high-temperature and high-pressure mechanical experiments, long-term thermal stability evaluation, and dynamic sealing experiments of fractured rock cores, the reinforcement and toughening laws and rheological control mechanisms of biochar on inorganic matrices were systematically studied. Research has found that a biochar content of 0.5 wt% can significantly improve the micro pore structure of the matrix. By utilizing its micro aggregate filling effect and interfacial chemical bonding, the compressive strength of the solidified body can be increased to over 2 MPa, and there is no significant decline in strength after aging at 130 °C for 30 days. More importantly, the unique “adsorption slow-release” mechanism of biochar effectively stabilizes the hydration reaction kinetics at high temperatures, extending the solidification time of the system to 15 h and solving the problem of flash condensation in deep well pumping. This system exhibits excellent shear thinning characteristics and crack sealing ability, and presents a unique “yield reconstruction” toughness sealing feature. This study elucidates the multidimensional strengthening mechanism of biochar in inorganic cementitious materials, providing technical reference for stable oil and water control in deep fractured reservoirs. Full article

This work contributes to advancing sustainable energy and waste management strategies by investigating the thermochemical conversion of food-based biomass through pyrolysis, highlighting the role of artificial intelligence (AI) in enhancing process modelling accuracy and optimization efficiency. The main objective is to explore the potential of underutilized biomass resources like spent coffee grounds (SCGs) and DSs (date seeds) for sustainable hydrogen production. Specifically, it aims to optimize the pyrolysis process while evaluating the performance of these resources both individually and as blends. Proximate, ultimate, fibre, TGA/DTG, kinetic, thermodynamic, and Py-Micro-GC analyses were conducted for pure DS, SCG, and blends (75% DS-25% SCG, 50%DS-50%SCG, 25%DS–75%SCG). Blend 3 offered superior hydrogen yield potential but had the highest activation energy (Ea: 313.24 kJ/mol), while Blend 1 exhibited the best activation energy value (Ea: 161.75 kJ/mol). The kinetic modelling based on isoconversional methods (KAS, FWO, and Friedman) identified KAS as the most accurate. These approaches work together to provide a detailed understanding of the pyrolysis process with a particular emphasis on the integration of artificial intelligence (AI). An LSTM model trained with lignocellulosic data predicted TGA curves with exceptional accuracy (R²: 0.9996–0.9998). Full article

This study addresses the challenges associated with deep-well drilling mud cuttings, including large waste volumes, high transportation costs, and complex organic pollutants. A low-cost synergistic technology was developed for the resource utilization of pyrolyzed drilling waste residue (PDWR) and the in situ remediation of oil-contaminated drill cuttings. A ternary photocatalytic system consisting of PDWR, H₂O₂, and oxalic acid was proposed and demonstrated to effectively degrade total petroleum hydrocarbons (TPH) in drill cuttings under solar irradiation. Systematic optimization identified optimal dosages of PDWR, H₂O₂, and oxalic acid as 250 mg, 280 mg, and 90 mg, respectively. The addition of oxalic acid significantly enhanced photocatalytic oxidation performance, increasing H₂O₂ utilization by 63.8% and improving the TPH degradation rate by a factor of 3.03. Under optimal conditions and 7 days of solar irradiation, TPH degradation efficiencies of 65.19–88.66% were achieved for initial TPH concentrations ranging from 5000 to 12,000 mg kg⁻¹. Mechanistic analysis revealed that a Fenton-like reaction between transition metals in PDWR and H₂O₂ dominated the photocatalytic process, while oxalic acid facilitated metal redox cycling through coordination and electron transfer, promoting sustained generation of reactive oxygen species (·OH). This study demonstrates a feasible and sustainable approach for high-value utilization of drilling waste residue and solar-driven in situ remediation of oil-contaminated drill cuttings, highlighting its strong potential for practical application. Full article

This paper proposes an innovative research algorithm “measurement—pattern—driving force—synergy” that determines the eco-efficiency of 83 Russian federal subjects (2000–2019) using the Slacks-Based Measure (SBM) model with non-desired outputs (incorporating comprehensive input indicators such as water resources and electricity input, and dual non-desired outputs of waste gas and wastewater). Combined with hot spot analysis, a gravity center model, and panel Tobit regression, we reveal the temporal-spatial evolution and driving mechanisms of eco-efficiency in resource-based economies. The research finds that the overall eco-efficiency of Russia is at a medium level and shows a dynamic correlation with the economic development stage. In the early stage of the period under review, there was a high degree of synergy, but the efficiency declined during the period of rapid economic growth. Later, it rebounded somewhat in tie with technological progress. Spatially, it presents a special pattern of low efficiency in the western European industrialized regions and high efficiency in the Arctic and Far East peripheral regions, reflecting the spatial heterogeneity of resource-dependent economies and the survival-constrained efficiency feature. The analysis of influencing factors indicates that per capita GDP has a significant positive driving effect on eco-efficiency, but the expansion of residents’ consumption, the improvement of education level and the dependence on foreign trade all have inhibitory effects, highlighting the path dependence of the current growth model on the structure of resource consumption. The research suggests that Russia should implement differentiated spatial governance in the future, promote the green transformation of consumption and trade structures, and strengthen the ecological orientation of the education and scientific research system to achieve a fundamental transformation of regional sustainable development from survival constraints to innovation-driven. Full article

This scoping study assesses practical aspects of electrokinetic (EK) biocementation of clay soil underneath a railway embankment ahead of upscaled testing to include a reduced-scale field pilot as an intermediate step towards subsequent pilot embankment treatment. It considers suitable field setups and performs Life Cycle Analysis (LCA) of biocementation by biostimulation of carbonic anhydrase (CA)-producing bacteria compared to hydrated lime slurry, if both treatments were implemented electrokinetically. LCA analysis was conducted using SimaPro software (version 9.6.0.1) with Ecoinvent database and bench-scale laboratory testing data. Electroosmotic flow modelling was performed to instruct on suitable setups and for estimates of power consumption towards the field application of 30 m of railway embankment and foundation soil. LCA indicated a considerable reduction in global warming if CA biocementation is used (0.00823 kg CO₂ eq for biocement vs. 0.022136 kg CO₂ eq for lime), and resource usage (7.06 × 10⁻⁵ kg Cu eq compared to 8.47 × 10⁻⁵ kg Cu eq for lime). Biocementation was more water-consuming compared to lime, as it involved multiple chemical solutions. Terrestrial acidification, aquatic eutrophication, and ecotoxicity were slightly higher for biocement, possibly due to system boundaries and processes assumed for material production. Further sustainability improvements would be possible if waste materials (e.g., captured industrial CO₂) could be used. Field trials will be essential for validation, system optimisation, and advanced model calibration. Full article

Coal gangue, the primary solid by-product of coal mining, presents severe environmental challenges due to massive accumulation. At the same time, it represents potential as a secondary resource if properly utilized. This review systematically summarizes the mineralogical characteristics, modification strategies, and utilization pathways of coal gangue. Current treatment methods, including thermal, chemical, and microbial activation, are discussed, highlighting their respective efficiencies, economic feasibility, and environmental impacts. Furthermore, this review emphasizes the transition of coal gangue from low-value disposal to high-value utilization. Representative applications are summarized, including its use as a precursor for advanced construction materials, as a functional material for environmental remediation, and as a feedstock for energy recovery. Finally, the major technological challenges and research gaps are identified. Future development should focus on intelligent sorting technologies, low-carbon activation processes, and synergistic multi-waste integration. These directions are expected to promote the transformation of coal gangue from an environmental liability into a valuable resource for the circular economy. Full article

With the rapid development of technology and increasing material consumption, the efficient management of waste streams has become a critical challenge within the circular economy, particularly in resource-intensive sectors such as electronic waste recycling. This study examines how artificial intelligence can improve the assessment and forecasting of circular economy investment efficiency, with particular attention paid to resource-intensive sectors such as electronic waste recycling. The study reviews data from European Union countries for the period 2010–2024, including economic, technological, and environmental indicators. A machine learning model system based on ensemble predictive methods was developed to assess the effectiveness of circular economy investments. The results show that artificial intelligence-based models have higher forecasting accuracy than traditional econometric methods, and the most important factors determining investment efficiency are the level of automation, recycling efficiency, and the stringency of environmental policies. The study provides a new, data-driven methodological approach to assessing circular economy investments and discusses their implications for sustainable real estate development and resource management. Full article

Global energy demand relies heavily on fossil fuels, which produce greenhouse gas emissions. Additionally, municipal solid waste, driven by population growth, represents another source of emissions. In Mexico, organic waste contributes 61 million tons of CO₂eq annually due to inadequate disposal. In Mérida, Yucatan, over 231,000 tons of organic waste are generated yearly, including Urban Tree Pruning (UTP) from 760 public spaces—a significant, undervalued lignocellulosic resource. This study presents a comprehensive, year-round compositional characterization of Mérida’s UTP to establish its chemical profile and assess its seasonal stability as a precursor for bio-based products (i.e., bioethanol). Characterizing local and stable feedstocks, such as UTP, is a fundamental step to enabling Mexico’s compliance with biofuel policies like the 5.8% gasoline blend mandate (NOM-016-CRE) and the Alcohol-to-Jet strategy, supporting progress toward SDGs 7, 11, and 13. Based on a stratified random sampling, monthly analysis (May 2024–April 2025) revealed a consistent biochemical profile with mean annual contents of 23.32% lignin and 62.46% holocellulose. Statistical analysis (Tukey’s test) confirmed its structural homogeneity throughout the year. This uniformity is a key operational attribute, as it allows for the use of standardized industrial pretreatment parameters. Furthermore, the characterized composition supports a theoretical ethanol yield of 170 g/kg of dry biomass, a value competitive with traditional feedstocks like sugarcane bagasse. Consequently, Mérida’s UTP is characterized as a reliable and consistent biomass resource, supporting a transition from linear waste disposal to a circular bioeconomy model. Full article

The concentration of heavy metals in the environment has been steadily increasing, raising concerns about their adverse effects on ecosystems and human health. Fine-grained particulate matter is of particular concern due to its enhanced mobility, bioavailability, and potential for inhalation exposure. Facilities involved in the mechanical processing of electronic waste (e-waste) represent a significant potential source of metal-containing fine particles. In this study, crushed e-waste components containing precious metals were separated into particle-size fractions ranging from 3.0 to 0.15 mm using a vibratory sieving system. The elemental composition of the individual fractions was determined by energy-dispersive X-ray fluorescence spectrometry (ED-XRF), while the spatial distribution of selected metals in fine fractions was further investigated using scanning electron microscopy combined with energy-dispersive X-ray spectroscopy (SEM–EDS). The results demonstrate that e-waste contains a wide range of heavy non-ferrous metals whose distribution is strongly dependent on particle size. A pronounced enrichment of metals was observed in the finest fractions, particularly below 0.25 mm. Compared to the coarse fraction (>3 mm), the zinc concentration increased by approximately one order of magnitude, while chromium, nickel, and cadmium exhibited increases of up to approximately 20-fold. Lead showed particularly high enrichment, reaching approximately 2 wt.% in the finest fraction (<0.15 mm), corresponding to nearly fiftyfold enrichment relative to the coarse fraction. Tin concentrations also increased markedly, in some cases by up to two orders of magnitude. Trace amounts of arsenic and selenium were detected in the finest fractions, whereas mercury was not detected. The combined ED-XRF and SEM–EDS results confirm that fine-grained e-waste fractions are the dominant carriers of hazardous metals and respirable particles generated during mechanical processing. These findings highlight the dual character of fine fractions as both a critical environmental and occupational risk and a potentially valuable secondary resource. The study emphasizes the importance of controlled handling, effective dust management, and targeted processing strategies to minimize human exposure while enabling efficient recovery of valuable metals from e-waste. Full article

The agri-food sector is undergoing a profound transformation driven by the combined pressures of climate change, resource scarcity, policy frameworks, and evolving consumer expectations. In this context, digital and green technologies have emerged as key enablers of more sustainable, transparent, and resilient food systems. This review provides a comprehensive overview of the conceptual foundations, technological drivers, and policy frameworks shaping the digital and green transition of the agri-food sector. Digital technologies—including precision agriculture, sensing and data acquisition systems, artificial intelligence, blockchain, and data platforms—are examined in relation to their role in improving resource-use efficiency, traceability, and decision-making across the food value chain. In parallel, green technologies and sustainable practices in food production, processing, and waste management are discussed, with emphasis on resource optimization, circular economy approaches, and environmental impact reduction. This review further highlights the role of European and global policy frameworks, such as the European Green Deal and the Farm to Fork strategy, in steering technological adoption and aligning innovation with sustainability objectives. By synthesizing technological, environmental, and policy perspectives, this work underscores the importance of integrated digital–green strategies for achieving long-term sustainability, competitiveness, and resilience in agri-food systems. Full article

Enhancing rice yield under high-input systems increasingly relies on optimizing physiological processes rather than further increasing external inputs. This study aimed to clarify the physiological basis underlying the yield advantage of super hybrid rice, focusing on photosynthetic capacity and assimilate transport. We compared super hybrid rice (Yliangyou 3218 and Yliangyou 5867) with super conventional rice (Zhendao 11 and Nanjing 9108) under field conditions in 2023–2024. Super hybrid rice consistently outperformed super conventional rice, with grain yield 19.7% higher in 2023 and 23.7% higher in 2024, primarily due to an increased number of spikelets per panicle, and grain yield was also positively correlated with photosynthetic capacity (net photosynthetic rate, stomatal conductance, maximum carboxylation rate, maximum electron transport rate and triose phosphate utilization rate). In 2024, spikelets per panicle and grain yield were also positively associated with phloem soluble sugar and vascular bundle number, indicating that enhanced assimilate transport contributed to higher spikelet formation. These results demonstrate that, compared to super conventional rice, the yield advantage of super hybrid rice is underpinned by coordinated enhancement of photosynthesis and assimilate transport, highlighting the importance of source–sink optimization for further yield improvement. Full article

This study reveals that a primarily ignored but crucial environmental situation—social crowding—can affect consumers’ sustainable behavior. The present research proposes a causal relationship between social crowding and consumer recycling behavior. Drawing on resource depletion theory and self-affirmation theory, three experiments were conducted across product recycling, participation in a brand-sponsored recycling program, and waste sorting activities. The results show that consumers exposed to crowded (vs. uncrowded) environments are less likely to engage in recycling. Study 1 provides initial evidence of this negative effect, demonstrating that it stems from crowd density rather than from the sheer number of people in the environment. Study 2 identifies ego depletion as the underlying mediating mechanism. Study 3 further demonstrates that self-affirmation attenuates the negative effect of social crowding on recycling behavior by mitigating ego depletion. These findings suggest that social crowding is an important situational barrier to recycling and that self-affirmation may serve as an effective intervention for promoting sustainable disposal behavior in dense consumption settings. This article concludes with a general discussion of the findings and practical implications for extending the relevant literature and benefiting consumer well-being, as well as promoting sustainable development. Full article

Phosphorus is a non-renewable resource critical for global food security, yet its natural reserves are rapidly depleting. Meanwhile, the poultry industry generates vast amounts of nutrient-rich waste that pose serious environmental risks if not managed properly. While valorizing these wastes offers a sustainable raw material alternative, investigating the environmental impacts of recovering them as a phosphorus source is crucial. This study evaluates phosphorus recovery from poultry litter via acid leaching following Hydrothermal Carbonization (HTC) and pyrolysis processes holistically. By conducting a Life Cycle Assessment (LCA) using this specific substrate and method combination, this work aims to provide comprehensive environmental insights. The impact assessment reveals that the total Global Warming Potential (GWP) is 6.00 kg CO₂ eq for the pyrolysis scenario and 4.18 kg CO₂ eq for the HTC scenario. Methodologically, a ‘system expansion’ approach was applied to integrate the avoided burdens from poultry manure management into the system boundaries. Furthermore, the inventory analysis revealed that chemical consumption (specifically NaOH and H₂SO₄) in the production process is the dominant factor not only for Global Warming Potential (GWP) but also across other environmental impact categories evaluated. The findings clearly indicate that chemical intensity predominantly determines the environmental performance across carbon footprint, acidification and other environmental impact categories. Full article

The rapid growth of polyethylene terephthalate (PET) waste and the limitations of conventional recycling methods for mixed waste streams emphasize the need for chemical recycling routes that deliver high-value monomers in a sustainable, resource-efficient manner. This work explores N-heterocyclic carbenes (NHCs) as organocatalysts for the glycolysis of PET with ethylene glycol to bis(hydroxyethyl)terephthalate (BHET), aiming for milder conditions and higher activity. A systematic catalyst screening links steric and electronic properties (percent buried volume, Tolman electronic parameter) of the NHCs to performance in the glycolysis process, resulting in a catalyst system with high PET conversion (up to 97%) and BHET yield (up to 65%). Mechanistic investigations (experimental and computational) support an anionic activation pathway for glycolysis. To lower the reaction temperature, selective cosolvent systems were explored, albeit with some loss of catalytic activity. Cooperative catalysis combining NHCs with Lewis acids enhances activity, leading to a high conversion (up to 90%) while maintaining lower temperatures than state-of-the-art glycolysis methods. The process was successfully transferred to post-consumer waste streams to validate the practicality. Full article

This study examines prospective teachers’ perceptions of sustainable development (SD) and explores the relationship between the SD scenarios they developed and the actions they performed. Based on 58 scenarios and 128 actions reported by pre-service teachers, the study found that scenarios primarily focused on education, resource conservation, and waste management. While the environmental dimension emphasized protection, economic and social dimensions were largely associated with financial savings and public welfare. In contrast, participants’ actual behaviors were predominantly limited to simple resource conservation, such as turning off lights and saving water. A significant discrepancy emerged: despite the strong emphasis on education-related themes in scenarios, educational actions were notably limited in practice. These results suggest that prospective teachers’ high cognitive awareness of SD is only partially reflected in their practical engagement. The findings highlight a “cognitive–practice gap,” underscoring the need for teacher education programs to prioritize action-oriented competencies. Full article