Process Safety and Environmental Protection最新文献

{"title":"PAHs in the sediments of the Shatt Al-Hillah River, Babylon, Iraq: Spatial and temporal distribution, pollution sources, human impacts, and treatment strategy","authors":"Osamah J. Al-sareji ,&nbsp;Ruqayah Ali Grmasha ,&nbsp;Miklós Jakab ,&nbsp;Mohammad Shahiq Khan ,&nbsp;Saiful Islam ,&nbsp;Tinku Biswas ,&nbsp;Mónika Meiczinger ,&nbsp;Csilla Stenger-Kovács","doi":"10.1016/j.psep.2025.107371","DOIUrl":"10.1016/j.psep.2025.107371","url":null,"abstract":"<div><div>This study investigated the spatial and temporal distribution, sources, and human health risks of 16 priority polycyclic aromatic hydrocarbons (PAHs) in the sediments of the Shatt Al-Hillah River, Babylon, Iraq. The concentrations of PAHs ranged from 1713.29 to 9996.47 ng/g dry weight, with high molecular weight PAHs (five- and six-ring compounds) dominating across all seasons. Molecular diagnostic ratios and principal component analysis revealed that the primary sources of PAHs were mixed pyrogenic and petrogenic emissions, including vehicular exhaust, industrial discharges, and biomass combustion. The Incremental Lifetime Cancer Risk (ILCR) values for adults and children at all sampling sites and during all seasons exceeded the acceptable threshold of 1 × 10⁻⁴, indicating a significant carcinogenic risk. Sediment washing using Triton X-100 followed by treatment of the washing effluent with activated carbon (AC) derived from wheat straw achieved PAHs removal efficiencies between 74.87 % and 94.43 %. The AC exhibited high reusability across three cycles. These findings highlight the urgent need for environmental management strategies and demonstrate the potential of using agricultural waste-derived AC as an effective, low-cost, and sustainable solution for remediating PAH-contaminated sediments.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"200 ","pages":"Article 107371"},"PeriodicalIF":6.9,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical simulation and optimization of flow field uniformity in a novel downward-sinking duct filter plate dust collector","authors":"Shihang Li ,&nbsp;Jiayi Li ,&nbsp;Shunyu Nan ,&nbsp;Hao Jin ,&nbsp;Shuda Hu ,&nbsp;Tianxiao Zhang ,&nbsp;Bin Yang ,&nbsp;Minghui Ouyang ,&nbsp;Lifeng He ,&nbsp;Bo Ren ,&nbsp;Yujie Huang","doi":"10.1016/j.psep.2025.107368","DOIUrl":"10.1016/j.psep.2025.107368","url":null,"abstract":"<div><div>Filtration technology is widely employed for dust control in long and narrow tunnels due to its high efficiency. However, the performance of long-box structure dust collectors is constrained by nonuniform internal flow-field distribution. In this study, a novel downward-sinking duct filter plate dust collector is proposed to enhance flow-field uniformity. Numerical simulations were conducted to compare the internal flow-field characteristics of the novel design with those of traditional cartridge dust collectors. Results demonstrate that the proposed dust collector outperforms conventional systems in key performance metrics, including mass flow rate, dust distribution, wind speed, turbulence intensity, and pressure uniformity. Notably, the novel design reduced mass flow rate distribution deviation by 23.6 %, dust distribution deviation by 29.7 %, and peak air velocity difference by 17 %, while improving pressure uniformity by 7 %. These optimizations significantly lowered operating resistance, enhanced filtration efficiency, extended equipment lifespan, and reduced energy consumption and maintenance costs caused by flow-field nonuniformity. This work provides a novel solution for optimizing filtration-based dust collectors in narrow-aisle tunnel applications, offering practical implications for improving dust removal performance and enhancing occupational safety.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"200 ","pages":"Article 107368"},"PeriodicalIF":6.9,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aluminium clay regulates oxidation dissolution mechanism of pyrite by solid film passivation layer and S, Fe, Al, Si speciation transformation","authors":"Bo Li ,&nbsp;Xuemei Wang ,&nbsp;Yao Ma","doi":"10.1016/j.psep.2025.107331","DOIUrl":"10.1016/j.psep.2025.107331","url":null,"abstract":"<div><div>Mining operations metallic sulfur minerals expose to oxidizing conditions, resulting in the production of acidic mine drainage (AMD). This work investigates how the inclusion of aluminous clay (AC) influences the speciation changes of sulfur (S), iron (Fe), aluminum (Al), and silicon (Si) on the surface of pyrite while it undergoes the bio-oxidative dissolution process. The results show that adding a small amount of AC (≤4.0 g/L) promotes the bio-oxidation of pyrite. Conversely, the addition of a larger amount of AC (&gt;4.0 g/L) inhibits the oxidation of pyrite. The oxidation process of pyrite conforms to the \"polysulfide-thiosulfate\" complex oxidation pathway. The breakdown of AC involves the consumption of H⁺ ions and the release of Al³⁺ ions. This process contributes to changes in hydrochemical composition, facilitating the hydrolysis of Fe³⁺ and Al³⁺ to create a secondary mineral layer on the pyrite's surface. This in turn, encourages the formation of FeS_n or Fe_1-xS. These findings suggest the potential to control the oxidative dissolution of pyrite by regulating the formation of a solid film passivation layer. This work gives a new insight into devising strategies aimed at remediation and treatment, presenting avenues to mitigate environmental pollution caused by AMD.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"200 ","pages":"Article 107331"},"PeriodicalIF":6.9,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coupled assessment and risk reconfiguration of debris hazards in natural gas pipeline incidents via multi-scale stochastic modeling","authors":"Xia Wu ,&nbsp;Mingxia Du ,&nbsp;Hanqing Liu ,&nbsp;Zihan Song ,&nbsp;Wenlong Jia","doi":"10.1016/j.psep.2025.107344","DOIUrl":"10.1016/j.psep.2025.107344","url":null,"abstract":"<div><div>Traditional risk assessment models for natural gas pipeline incidents predominantly focus on jet fire thermal radiation zones, while secondary hazards caused by ejected debris—owing to challenges in quantifying the randomness of debris quantity, mass, and ejection trajectories—are often underestimated. This study proposes a multi-scale coupled model integrating stochastic debris generation mechanisms and physical ejection processes to reconfigure the dynamic propagation pathways and spatial risk distribution of debris hazards. Leveraging statistical analysis of 95 global pipeline rupture incidents from 1954 to 2024, we established a probabilistic database for debris quantity, mass distribution, and ejection angles. A cohesive crack model was employed to simulate debris generation, with Monte Carlo methods addressing ejection parameter uncertainties. Validated against the 2009 pipeline rupture incident in Ontario, Canada, the model predicted that 97.2 % of debris landed within 150 m of the rupture site, aligning closely with observed maximum ejection distances. Full-scale simulations for pipeline section 100–4 revealed a maximum debris flight distance of 263.6 m, surpassing the thermal radiation boundary (222.9 m) calculated by the ASME B31.8S standard. This study exposes the systemic underestimation of hazard zones by conventional thermal radiation models and advocates integrating debris dynamics assessments into intelligent pipeline safety management systems. Furthermore, the proposed probabilistic-physical coupling framework supports multi-hazard synergy analysis (e.g., thermal radiation-debris-soil erosion interactions), offering a decision-making paradigm for high-precision pipeline design, resilient urban infrastructure planning, and energy transportation risk mitigation in the context of carbon neutrality349.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"200 ","pages":"Article 107344"},"PeriodicalIF":6.9,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The reaction laws and toxicity effects of synthetic phenolic antioxidants (SPAs) in wastewater and atmosphere: A theoretical investigation","authors":"Shengming Wang ,&nbsp;Huidi Zhang ,&nbsp;Xiangli Shi ,&nbsp;Qingzhu Zhang ,&nbsp;Yuchao Ren ,&nbsp;Jiaqi Chen ,&nbsp;Haolin Wang ,&nbsp;Wenxing Wang ,&nbsp;Qiao Wang","doi":"10.1016/j.psep.2025.107324","DOIUrl":"10.1016/j.psep.2025.107324","url":null,"abstract":"<div><div>Synthetic phenolic antioxidants (SPAs) are widely added to fats and fried foods as food additives. Their hazards to humans and the environment cannot be ignored. The degradation mechanism of three SPAs (butyl hydroxyanisole (BHA), dibutyl hydroxytoluene (BHT) and <em>tert</em>-butyl hydroquinone (TBHQ)) by superoxide radical (O₂^•-), SO₄•^-, O₃ and •OH is investigated using density functional theory (DFT) method. In the atmosphere, the •OH-addition products of TBHQ will react with O₂ and NO, and in the wastewater, TBHQ-OH intermediates will react with O₂ and HO₂• to generate products. The results showed that the activation energies (Δ<em>G</em>^<em>≠</em>) of the addition reactions of TBHQ with OH and O₃ in wastewater systems were 2.59–6.23 kcal/mol and 10.29–20.35 kcal/mol, respectively, which were significantly lower than those of the gas-phase reactions (4.91–9.74 kcal/mol and 16.69–24.57 kcal/mol), indicating the high efficiency of liquid-phase degradation. The rate constants for the degradation of the three SPAs by different ROS are in the following order: •OH ≈ SO₄•^- &gt; O₃ &gt; &gt; O₂^•-. The half-life <em>t</em>_1/2(SO₄•^-) of SPAs is 0.013–151.06 s in the range of 273–313 K and [SO₄•^-] of 10⁻¹³ to 10⁻⁹ mol L⁻¹. These three SPAs are hardly persistent in the environment. As for TBHQ, the toxicity of the ring-opening products P2, P3, P4 and P5 was significantly lower relative to TBHQ. The degradation half-lives (t_1/2) of SPAs by advanced oxidation processes (AOPs) based on SO₄^- in the range of 273–313 K were 0.013–151.06 s, indicating their efficient degradation properties.The toxicity of its degradation products of SPAs are effectively reduced. This work provides theoretical support for the degradation of SPAs by advanced oxidation processes (AOP) based on SO₄•^- and •OH.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"200 ","pages":"Article 107324"},"PeriodicalIF":6.9,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molten salt thermal treatment for carbon fiber composites recovery: Structural effects on thermosetting resin degradation mechanism","authors":"Yang Ren ,&nbsp;Zuozheng Lin ,&nbsp;Jing He ,&nbsp;Hongyun Hu ,&nbsp;Yongda Huang ,&nbsp;Xian Li ,&nbsp;Hong Yao","doi":"10.1016/j.psep.2025.107352","DOIUrl":"10.1016/j.psep.2025.107352","url":null,"abstract":"<div><div>Recovering carbon fibers from thermosetting composites is challenging due to stable cross-linked resins and poor heat transfer. Previous research introduced a molten salt thermal treatment method to enhance heat transfer and reactivity for recycling clean and high-strength fibers. However, the diverse resins significantly influence conversion properties, affecting fiber recovery and resin utilization. Expanding on this resins with varying structures were studied, being phenol-rich (EP), ester-rich (PA), and blended (VE). Pyrolysis achieved fiber separation with &lt; 5 % residual resin and &lt; 1 % strength loss for all resins. Despite structural differences, the resins showed similar radical production (hydrogen and methane), but liquid oil compositions varied. VE and PA yielded aromatic hydrocarbons, while EP produced nitrogen compounds and phenols. Specifically, molten salt significantly disrupted the cross-linked structures, as evidenced by increasing NH₃ emissions from amine-cured EP resin. For ester-rich resins, the strong alkalinity of the molten salt effectively promoted decarboxylation, liberating aromatic hydrocarbons. For phenol-rich resin, depolymerization at 400 °C liberated phenolic hydroxyl groups that reacted with the molten salt to form sodium phenolate. Subsequent temperature elevation to 450–500 °C induced polycondensation, yielding char precipitation. These findings facilitate fiber recovery and resin byproduct utilization.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"200 ","pages":"Article 107352"},"PeriodicalIF":6.9,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sustainable recovery of benzene and tert-butanol from wastewater using energy-efficient heterogeneous azeotropic pressure-swing distillation with multi-objective optimization","authors":"Tan Dai,&nbsp;Jinlong Li,&nbsp;Hui Wang,&nbsp;Ruimin Zhang,&nbsp;Qing Ye","doi":"10.1016/j.psep.2025.107317","DOIUrl":"10.1016/j.psep.2025.107317","url":null,"abstract":"<div><div>The wastewater generated in the production process of tert-butanol usually contains benzene and tert-butanol, but benzene, tert-butanol and water can form a mixture which exhibits one ternary azeotrope and three binary azeotropes. This system is pressure-sensitive, and its ternary phase diagram features a heterogeneous region. Accordingly, changing the operating pressure or using a decanter for natural liquid-liquid separation are proposed for separating the mixture. The NSGA-II algorithm is utilized for multi-objective optimization of these separation processes to identify the optimal scheme. In comparison to the pressure-swing distillation (PSD) and heterogeneous azeotropic distillation (HAD), the heterogeneous azeotropic pressure-swing distillation (HAPSD) process demonstrates superior performance. Compared to the PSD-2 process, the total annual cost (TAC), exergy destruction, the total energy consumption (TEC) and CO₂ emissions of the HAD process are reduced by 41.00 %, 41.68 %, 19.79 % and 40.55 %, respectively, while those of the HAPSD process are reduced by 64.55 %, 67.73 %, 45.30 % and 68.10 %, respectively. Additionally, the HAPSD process incorporates heat pump technology and heat integration technology to minimize energy demand. The results reveal that the HAPSD process combined with heat integration and heat pumps outperforms the PSD process and HAD process. Specifically, compared with the PSD process, it achieves significant reductions in various indicators: 75.47 % in TAC, 88.94 % in TEC, 88.10 % in gas emissions, and 87.87 % in exergy destruction, respectively.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"200 ","pages":"Article 107317"},"PeriodicalIF":6.9,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural optimization of downhole axial-flow cyclone separation pipe string","authors":"Minghu Jiang ,&nbsp;Xinya Li ,&nbsp;Lei Xing ,&nbsp;Lixin Zhao ,&nbsp;Duo Liu ,&nbsp;Shuai Guan","doi":"10.1016/j.psep.2025.107332","DOIUrl":"10.1016/j.psep.2025.107332","url":null,"abstract":"<div><div>Single-well injection-production technology (SWIPT) is an effective solution for the economic development of high-water-cut oilfields, with downhole oil-water separation playing a crucial role in ensuring its efficient operation. In order to meet the 5.5-inch casing size requirements of onshore oilfields and enhance the separation performance of single-well injection-production technology, a dual-pump suction single-well injection-production technology (DPS-SWIPT) was innovatively proposed, and an axial-flow cyclone separation pipe string (AFCSPS) was designed. The significance of structural parameters affecting the AFCSPS separation performance is calculated based on the Plackett-Burman (PB) design method. Response surface methodology (RSM) and artificial intelligence (AI) algorithms were employed to optimize the structural parameters of the cyclone separation pipe strings. A multivariate response mathematical model has been developed to quantitatively describe the relationship between structural parameters and separation efficiency. A comparison of the optimization methods reveals that the sparrow search algorithm back propagation neural networks-genetic algorithm (SSABP-GA) optimization algorithm yields the best results, with the value of separation efficiency reaching 99.93 %. The separation efficiency of the hydrocyclone remained above 95.38 % across various operating and physical parameters, indicating that the optimal structure demonstrates a high degree of adaptability within the studied range. Numerical simulations and experimental results show good agreement for oil core morphology and separation efficiency, within an average efficiency error of 1.48 %. The study can provide support and reference for the application of the equipment in downhole oil-water separation technology.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"200 ","pages":"Article 107332"},"PeriodicalIF":6.9,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MIL-101(Cr)/epoxy composite coating for enhanced corrosion resistance in concrete sewer infrastructure","authors":"Sagor Kumar Pramanik ,&nbsp;Muhammed Bhuiyan ,&nbsp;Dilan Robert ,&nbsp;Rajeev Roychand ,&nbsp;Li Gao ,&nbsp;Biplob Kumar Pramanik","doi":"10.1016/j.psep.2025.107360","DOIUrl":"10.1016/j.psep.2025.107360","url":null,"abstract":"<div><div>Concrete sewer systems are essential to urban infrastructure but are highly susceptible to microbial-induced corrosion (MIC), leading to severe structural degradation and substantial maintenance costs. This study develops a MIL-101(Cr)/epoxy composite coating to mitigate MIC and enhance concrete durability in aggressive environments. MIL-101(Cr) nanoparticles were synthesized via a scalable hydrothermal process and incorporated into epoxy matrices at varying concentrations (0.5 %, 1.0 %, and 1.5 % by weight). The optimized 1 wt% MIL-101(Cr)/epoxy composite exhibited remarkable corrosion resistance, reducing weight loss to 5.2 % after 65 days of sulfuric acid exposure, improving performance by 78.3 % over uncoated concrete and 70.6 % over pure epoxy coatings. Water absorption was minimized to 0.12 %, ensuring superior moisture resistance and long-term durability. The composite coating achieved a pull-off strength of 6.12 MPa, a 48.5 % enhancement over conventional epoxy coatings, highlighting its strong adhesion and structural integrity. Thermogravimetric analysis showed improved thermal stability, with dehydration peaking at 173.6 °C. Density Functional Theory (DFT) calculations further validated the experimental findings, demonstrating enhanced electron-donating and electron-accepting properties that contribute to the composite’s outstanding anti-corrosive performance. This study demonstrates that MIL-101(Cr)/epoxy composites are a promising and sustainable solution for extending the service life of concrete sewer infrastructure in corrosive environments.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"199 ","pages":"Article 107360"},"PeriodicalIF":6.9,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144124629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functional group-driven modulation of combustion-gas kinetics in underground coal enhanced combustion","authors":"Hengyi He ,&nbsp;Baisheng Nie ,&nbsp;Peng Liu ,&nbsp;Jijiang Huang ,&nbsp;Hao Zhang ,&nbsp;Yanan Hou ,&nbsp;Kaidan Bai","doi":"10.1016/j.psep.2025.107359","DOIUrl":"10.1016/j.psep.2025.107359","url":null,"abstract":"<div><div>Enhanced combustion coupled with in-situ thermal energy extraction in underground coal seams represents a novel paradigm-shifting strategy for coal resource extraction through in-situ chemical fluidized mining. Systematic investigation into the combustion dynamics and reactive gas evolution under injection-enhanced conditions provides validation for optimizing this in-situ thermo-chemical conversion process. This study elucidates the metamorphic dependence of coal combustion through combined FTIR and TG-FTIR analyses, delineating functional group evolution and gaseous emission dynamics across coals of different metamorphic grades. The results indicate that the intensification of the coal metamorphism, characterized by increased multi-substituted aromatic groups (2 adjacent H deformation) and stable OH-π structures, alongside reduced active oxygen-containing groups (conjugated C<img>O and -COOH) and asymmetric aliphatic chains, collectively diminishes the coal ignitability. Combustion performance indices reveal that low-metamorphic-degree coal exhibits enhanced ignition and combustion efficiency at lower temperatures, whereas high-metamorphic-degree coals demonstrate inferior ignitability but achieve higher combustion rates. Highly metamorphosed coal typically exhibits lower CO₂ emission intensity and higher CO emission intensity due to incomplete oxidation. This divergence in combustion products directly correlates with enhanced oxygen demand requirements for complete oxidation at higher metamorphic stages. CH₄ emission predominantly occurs within the 200–700℃ thermal regime, with 400°C serving as a critical thermal demarcation point for the peak CH₄ release intensity from coals of varying metamorphic degrees. NO is the main component of the harmful gas NO_x, and highly metamorphosed coal releases less NO. Ignition propensity demonstrates linear dependence with -COOH, and the burnout efficiency exhibits proportional enhancement of the 3 adjacent H deformation. OH-OH, asym. R₂CH₂, and asym. RCH₃ collectively control the volumetric release of gaseous species during coal combustion. These findings offer a scientific basis for optimizing underground coal combustion systems by strategically utilizing natural variations in coal maturity.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"200 ","pages":"Article 107359"},"PeriodicalIF":6.9,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}