ACS Omega
·
2024
·
IF 3.7
Yan Jingjing,Li Yifang,Wang Fei,Li Junpeng,Liu Hongwei,Pei Zhengyu,Gao Haidong
The dynamics of droplets spreading on surfaces have been extensively studied across various influencing factors, necessitating an exploration of their effect on wettability. Herein, the specific composition, size distribution, and contact angle of the coal dust preparation were characterized by a series of experiments to determine the conditions for the simulation. Meanwhile, the multiphase volume of the fluid method was implemented in the simulations, predicated on appropriate boundary conditions, and verified by a mesh independence test. The findings confirmed that the numerical approach for contact angle validation had a minor deviation, making it suitable for multiphase interface tracking. Besides, the typical wetting pattern of droplets was hereby identified into three stages, including the moving stage (stage I), the periodic wetting stage (stage II), and the balancing stage (stage III). The initial diameter could effectively increase the coverage area and spreading time for stage II. Obviously, the first amplitude of first maximum spreading diameter (Dmax-1) significantly increased with higher impact velocities, corresponding to an increase in kinetic energy. Despite the significant spreading effect of the falling height mainly on Dmax-1 and contact time, the increased trend of wetting efficiency was not obvious. However, the spreading factor and wetting efficiency decreased with increased roughness height. Finally, the difference in spreading wettability was illustrated based on the spreading wetting mechanism. The wetting efficiency of droplets on coal dust was remarkably influenced by the dynamic spreading behaviors of droplets. Overall, the findings from this study offer insights into the extent of spreading wetting that occurs before a droplet reaches an equilibrium state.
研究领域:
能源科学
·
流体力学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2021
·Vol. 45
·期 37
·17461-17474
·
IF 3.591
Shuili Lai,Gong Chen,Wen Hu,Baojian Liu,Xin Yang,Kai Gao
Aiming to reduce coal dust pollution and spontaneous coal combustion during coal mining, storage, and transportation, a kind of DOPO-nano-SiO2 modified polyacrylic acid-based polymer flame retardant dust suppressant for coal was fabricated using 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), γ-aminopropyl triethoxysilane (KH550), nano-SiO2, sodium alginate (SA), and acrylic acid (AA) as raw materials, potassium persulfate (K2S2O8) and sodium bisulfite (NaHSO3) as initiator, and N,N′-methylenebisacrylamide (MBA) as a cross-linking agent by the aqueous solution polymerization method. The product was characterized and analyzed by FT-IR, XPS, XRD, GPC, TG, and DSC techniques. Its flame retardant property, thermal stability, and dust suppression performance were tested, and the activation energy of the pyrolysis reaction was calculated using Flynn–Wall–Ozawa (FWO) method. Compared with the coal sample sprayed with water, the CO mass concentration of the coal sample sprayed with flame retardant dust suppressant was decreased by 80.6%, inhibition rate reached 82.8%, LOI value was 26.1%, and the UL-94 rating was V-0. Moreover, the initial degradation temperature and pyrolysis activation energy were increased by 10.6% and 108%, respectively. After spraying the flame retardant dust suppressant, the pulverized coal particles were tightly bonded together to form a flexible consolidation layer, thereby inhibiting coal dust pollution and loss. The water loss rate, wind erosion loss rate, and oscillation loss rate were decreased by 56.9%, 98.7%, and 97.5%, respectively. These results revealed that the pulverized coal sprayed with the flame retardant dust suppressant exhibited better flame retardant property, thermal stability, and dust suppression performance than that sprayed with water. In summary, the flame retardant dust suppressant prepared in this work could play a key role in inhibiting coal dust pollution and spontaneous coal combustion.
研究领域:
材料科学
·
环境工程
·
矿业工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY
·
2022
·
IF 8.857
Qi Zhao,Yi Li,Xianfeng Chen
The study aims to examine the suppression performance of an inhibitor after a methane/coal dust explosion. The design of an explosion suppression system included the carrier gas of nitrogen (N 2 ) with an inhibitor of ammonium polyphosphate (APP). The study investigated fire extinguishing and explosion suppression of methane/coal dust by N 2 /APP in a vertical pipe. Flame propagation characteristics were measured by a high-speed camera, micro-thermocouple, and pressure sensor . The residues after the explosion were characterized chemically by X-ray photoelectron spectroscopy, and the thermal decomposition characteristics of coal dust and APP in the N 2 atmosphere were analyzed by synchronous thermal analysis. Experimental results show that the explosion suppression system can effectively hinder the flame propagation of methane/coal dust explosion. The flame height, bottom velocity, and temperature were all weakened significantly. The optimum level of suppressant minimizes the explosion pressure and suppresses the flame significantly. In addition, the fire extinguishing and explosion suppression mechanisms of N 2 /APP were summarized. The suppression method used in this study blocks the explosion after it occurs rather than preventing it through premixed inerting.
研究领域:
安全工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Jianqiang Yin,Hongzheng Zhu,Liang Yuan,Bingyou Jiang,Gaochao Pan,Wenliang Zhu,Qinghui Shi
Using the high-speed motion acquisition system, we studied the adhesion ability and wetting ability of coal dust under the effect of four octanol solutions. The adhesion ability followed the order: 2-Octanol > 4-Octanol > 1-Octanol > 3-Octanol. The wrap angle of coal dust on the octanol surface exhibited an increasing trend with the rise in coal proportion of dust. The observed behavior was substantiated by the interaction force, ascertained through molecular dynamic simulations. The interaction force between coal dust and 3-Octanol was the smallest leading to the weakest adhesion ability by the 3-Octanol solution. The contact angle of octanol solution droplet at the coal dust surface under the same octanol concentration was investigated to follow the order: 2-Octanol > 4-Octanol > 1-Octanol > 3-Octanol. The wetting velocity decreased as the coal proportion of dust increased. The wetting ability followed the order: 2-Octanol < 4-Octanol < 1-Octanol < 3-Octanol. The surface energy of dust increased as the coal proportion decreased. The dedusting efficient under the effect of octanols depended on the difference in surface energy between the coal dust and the octanol solution. The greater the Δ γ (difference between the surface energy of the dust and solution), the weaker the adhesion ability, and the stronger the wetting ability. The findings of our study can offer valuable insights for the development of dedusting reagent design.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Wenjin Niu,Wen Nie,Qiu Bao,Qifan Tian,Ruoxi Li,Xiaohan Zhang,Chenfeng Shi,Ke Tong,Zhihui Zhang
The wettability of coal dust by surfactant-regulated solutions is influenced by the hydrophilic structures of the surfactants. This study combines macro- and microscopic experiments to determine the wettability performance of four surfactants with identical hydrophobic groups but different hydrophilic groups. Through molecular simulation, a molecular-level evaluation standard for the surfactant’s impact on coal dust wettability was established. Additionally, the correlation mechanism between the electrostatic potential distribution of the hydrophilic groups and their wettability was identified. Sulfonic groups—compared with sulfate, hydroxyl, and amino groups—can more effectively enhance the solution’s wettability, reducing the solution’s surface tension to as low as 22.1 mN/m and achieving a molecular wettability area of 78.84. Furthermore, the electrostatic potential extreme of the sulfonic group was − 53.61 kcal/mol, with an electrostatic potential wettability area of 28.99 Å2. This represents an improvement of approximately 34.43 % and 5170.91 %, respectively, compared with hydroxyl groups. Greater electrostatic potential extremes and electrostatic potential wettability areas led to stronger electrostatic adsorption, more adsorbed water molecules, and better wettability of coal dust. This study provides theoretical guidance for the rational design of functional surfactants for surface engineering and pollution control applications.
研究领域:
环境科学
·
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
COMBUSTION SCIENCE AND TECHNOLOGY
·
2021
·
IF 2.174
Jian Su,Yang Cheng,Shi Song,Hong Ma,Wen Wang,Yu Wang,Shi Zhang
In the paper, explosion characteristics of coal dust in the presence of strong oxidant were studied using a 20-L spherical vessel, and the influential factors, including air relative humidity, ambient temperature and combustible gas of hybrid explosion were investigated. Results showed that sodium chlorate dust could increase the explosion severity of coal dust to some extent, while the power of hybrid explosion was weakened for the increasing content of its decomposition product. The explosibility of blend samples both presented a trend of increasing at low air relative humidity and then deceasing at high air relative humidity. The explosion severities of blend samples were strengthened for the increasing ambient temperature in a certain range. CH4 had a promotion effect on the explosion performance of Blend A, and Pmax and (dP/dt)max values of Blend A dust explosion, respectively, increased by 56.1% and 200% with the addition of CH4. While the explosion severity of Blend B was promoted for adding a small amount of CH4, but suppressed for a high CH4 content. The experimental results have guiding significance for the risk assessment of coexistence of coal dust and hazardous chemicals, especially in confined space.
研究领域:
安全科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Yongliang Liu,Hongmei Li,Jing Xie,Luming Li,Jie Deng,Chuntian Qiu,Yong Zhang,Lanjie Wang,Yuhang Tian
The wettability of bituminous coal is critical for the coal dust suppression and can be apparently modulated by ionic liquids. However, the modulation mechanism still remains elusive. Here, a combination of macroscopic experiments, mesoscopic characterization, and microscopic simulations (quantum mechanics and molecular dynamics) are leveraged to parse the effect on the wettability of coal dust surfaces of three novel ionic liquids ([C 12 MIm]Br, [BMIm]Br, [BMIm]Cl) featuring the varying chain lengths and anions in the coal-water system. The results show that the selected ionic liquids exert a distinct bridging function from traditional surfactants which invoke the hydrogen bonding interaction. This ionic liquids-mediated bridging mechanism heavily depends on their chain length structure, which can firstly penetrate deeply the internal pores of coal dusts and then adsorb on the coal surfaces to rapidly strike a dynamic equilibrium. Ionic liquids interacting with coal dust can primarily reduce the energy difference between polar and nonpolar interactions within coal dust, thereby enhancing the electrostatic interactions between coal dust and water molecules and effectively improving coal dust wetting properties. These findings provide a theoretical basis for the rational design of high-performance ionic liquids for coal mine dust control.
研究领域:
能源科学
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Zikang Lin,Xianfeng Chen,Chaohang Xu,Hetang Wang,Xiaolong Zhu
In order to investigate the feasibility of ionic liquid-surfactant compound solutions for coal dust suppression, three ionic liquids and sodium alpha-olefin sulfonate (AOS) were selected to be compounded respectively. The compound solutions were optimized by surface tension tests and coal dust settling experiments, and FTIR and SEM tests were carried out on coal samples treated with the optimum wetting agent. The results show that when the concentration is 0.3 wt%, and the ratio of [Bmim][Cl]/AOS is 4:6, the wetting rate of compound solution is the maximum. The content of hydrophilic functional groups OH…O and C-O in the coal samples increases significantly, and the degree of benzene ring substitutions is elevated; while hydrophobic functional groups –CH, aromatic ring C = C, and benzene ring 3 substitutions (3H) are destroyed by dissolution. The micromorphology of the coal surface changes with the appearance of many cracks and pores and an increase in surface roughness. [Bmim] + can adsorb on the drain absorption points on the coal surface by electrostatic effect, turning them into water absorption sites and attracting the surrounding AOS molecules to arrange the composite adsorption layer more closely. These results can contribute to the development of novel wetting agents with specific structures and provide theoretical guidance for the reduction of coal dust concentrations.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Jiajun Li,Shaoqi Kong,Guochao Yan,Xuanlai Chen
The serious hazards posed by inhalable coal dust to the safety, air purity, and health of coal miners can be effectively alleviated through the use of appropriate dust suppressants. The wetting enhancement capabilities of two dust suppressants, octylphenol polyoxyethylene ether (OP-10) and nonylphenol polyoxyethylene ether (NP-10), were examined in this study through experimental and simulation methods. Macroscopic experiments (surface tension, contact angle, coal dust settling time, and water retention) indicate that the shorter the alkyl chain attached to the benzene ring in the surfactant and the lower the surface tension, the more conducive it is to improving the fluidity and suspension stability of anthracite particles in the wetting solution and further improving the interfacial properties and wetting effect between coal dust and the liquid medium. Mesoscopic experiments (laser particle size, FTIR, XPS, UV–visible spectroscopy, BET, and SEM) showed that the relevant properties of APEO-modified coals were greatly changed, especially the anthracite modified with short-chain alkyl groups of OP-10, which exhibited a stronger aggregation effect on the coal dust particles and increased the pore structure and specific surface area of the coal dust. Additionally, the hydrophilic functional groups are augmented, leading to a notable enhancement in the adsorption capacity of OP-10 on the coal surface. Microscopic simulations (Density Functional Theory calculations, Molecular Dynamics simulations) reveal that APEO surfactants with longer alkyl side chains attached to benzene rings hinder the π-π interactions between the coal's aromatic ring structures and the benzene rings in the surfactants. The surface polarity of coal modified with OP-10 is significantly enhanced, resulting in a more pronounced improvement in wetting performance and an increased water retention capability. The study systematically explores surfactant microstructure effects on anthracite wetting, laying essential groundwork for advanced dust suppression system development.
研究领域:
环境科学
·
材料科学
·
计算化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL ENGINEERING
·
2024
·Vol. 150
·期 12
·04024056
·
IF 1.6
Felicie Mwabaima Ilele,Wen Nie,Stephen Nyabire Akanyange,Tian Qifan,Bao Qiu,Fei Liu
In the industrial mining environment, coal dust pollution has been a persistent issue, causing harm to both human health and the ecosystem. Starch–based polymers have emerged as promising solutions for dust suppression in mines. These polymers not only effectively control dust dispersion but also offer environmental benefits. Derived from natural sources and biodegradable, starch–based polymers align with sustainability concerns in resource extraction industries. Their ability to bond with coal dust particles improves air quality and safety for workers and communities. Sustainable practices are essential to mitigate the environmental and health impacts of coal mining despite its importance in global energy production. The thesis research focused on creating an environmentally friendly dust suppressant gel, CSS-g-AA-AEO 0.04%, to tackle the ongoing problem of coal dust pollution in mining environments. The researchers combined cassava starch with acrylic acid using graft copolymerization techniques to yield the innovative CSS-g-AA gel. Structure tests using x-ray diffraction and infrared spectroscopy (IR) clearly showed that the grafting process was successful, indicating that the gel was flexible and could be used for various applications. Extensive research efforts, including simulations, precise surface tension measurements, and comprehensive contact angle analyses, led to the identification of a surfactant with exceptional wetting properties, a 0.04% AEO surfactant. scanning electron microscope (SEM) and EDS analyses showed that the dust suppressant had good adhesion and adsorption effects on coal. The water retention capability exhibited an evaporation percentage of 90.94%, whereas wind erosion control achieved a lower dust suppression of 16.2%. This difference is of particular significance, especially under challenging high wind conditions. Incorporating starch solidification within the gel further bolstered its efficacy as a sustainable solution for coal dust suppression, emphasizing its potential as a game-changing approach to combating coal dust pollution while advocating for sustainable mining practices. These groundbreaking findings underscore the immense promise and viability of CSS-g-AA-AEO 0.04% as a cutting-edge, environmentally conscious strategy to mitigate coal dust pollution and promote sustainable mining practices for a cleaner and healthier environment.
研究领域:
环境科学
·
材料科学
·
矿业工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2020
·
IF 5.647
Tao Fan,Zhenyi Liu,Jiting Ouyang,Mingzhi Li
Coal dust diffusion during coal transportation and storage causes serious environmental pollution . The existing dust suppressant in previous studies was unable to achieve the expected effects owing to severe wind damage and rain erosion. Therefore, the current study synthesized and prepared an efficient and applicable dust suppressant for coal transportation and storage. Infrared spectroscopy and scanning electron microscope experiments were conducted during the synthesis to analyze the microstructure changes in the synthetic products. Moreover, viscosity was used as the evaluation index in the single-factor experiments to obtain the optimal synthesis conditions. Performance measurement results showed that the prepared dust suppressant had a strong protective effect on coal powder and could effectively resist the impact of wind damage and rain erosion. Compared with other dust suppressants, the proposed dust suppressant prepared showed more evident positive effects and longer lasting action time in the quantitative test. Moreover, the dried product could synergistically combust with coal powder, thereby possibly mitigating the tedious post-treatment process and increasing the utilization rate of resources.
研究领域:
能源与环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
GEOFLUIDS
·
2024
·Vol. 2024
·期 1
·9112308
·
IF 1.2
Hongmei Li,Yun Zhao,Jie Deng,Jing Xie,Weiqi Zhou,Yiting Liu,Luming Li,Futing Xia,Rui Qi
The optimization of coal dust management in fluidized mining environments is of paramount importance, yet it is currently impeded by a gap in understanding chemical dust suppression mechanisms. This study combines indoor experiments with molecular simulation to investigate the mechanisms by which three anionic surfactants with different hydrophilic and hydrophobic groups (SDBS, SDS, and SLS) influence coal wettability. Using hydrophobic bituminous coal as the experimental subject, basic physical and chemical properties are analyzed through proximate analysis, XRD, and FTIR. The effect of different surfactants on coal wettability is characterized based on sedimentation experiments, while the coal–surfactant–water three-phase model examines the equilibrium adsorption configuration, water molecule diffusion coefficient, and interaction energy in different adsorption systems. The surface free energy of coal dust and its components is measured before and after surfactant adsorption, verifying the adsorption-wetting mechanism of surfactants at the coal–water interface. Results show that anionic surfactants enhance wettability through a bidirectional adsorption mechanism at the coal–water interface: the hydrophobic tail adheres to the coal surface via van der Waals forces, while the hydrophilic head faces the water phase, driven by electrostatic and hydrogen bonding interactions. This coordinated adsorption process alters water diffusion and the surface free energy of coal, thereby improving wettability. SDBS, due to its benzene ring, significantly amplifies the bidirectional adsorption effect, achieving the most substantial improvement in coal dust wettability. The findings provide a robust theoretical framework for developing dust control strategies in fluidized mining operations, advancing the field toward more efficient and sustainable mining practices.
研究领域:
矿业工程
·
化学工程
·
计算科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）