Influence of particle diameter on the wettability of coal dust and the dust suppression efficiency via spraying

Currently, spraying is a main means for dust prevention and control in underground coal mines. The dust-suppression efficiency via spraying is highly correlated with the wettability of coal dusts. There are many factors affecting the wettability of coal dust, among which coal’s metamorphic degree has great influence. In order to gain in-depth knowledge of the effects of coal metamorphic degree on coal dust wettability and the dust-suppression efficiency via spraying, 6 coal dust samples with different metamorphic degrees were collected and used in the study. In the experiments, the microproperties, wetting performance, and dust-suppression efficiency via spraying were measured. According to the experimental results of coal’s microproperties, with the improvement of metamorphic degree, the content of hydrophilic oxygen-containing functional groups on the surface, the surface roughness, the specific surface area, and the interpore diameter all decreased. In addition, as coal’s metamorphic degree was enhanced from lignite to meager-lean coal, the wettability of the coal dust dropped. On the other hand, as the metamorphic degree of coal quality continued to be improved to anthracite, the wettability of the coal dust increased instead. The measured results revealed that the dust-suppression efficiency via spraying was highly correlated with the wettability of coal dust. The coal dust with better wettability exhibited higher dust-suppression efficiency via spraying. With the increase of water-supply pressure, the effect of coal dust wettability on the dust-suppression efficiency via spraying was weakened, and the difference of dust-suppression efficiency among different coal dust samples was narrowed.

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Evaluation of the coal dust suppression efficiency of different surfactants: A factorial experiment

Colloids and Surfaces A Physicochemical and Engineering Aspects ◽

10.1016/j.colsurfa.2020.124686 ◽

2020 ◽

Vol 595 ◽

pp. 124686 ◽

Cited By ~ 1

Author(s):

Ping Chang ◽

Zidong Zhao ◽

Guang Xu ◽

Apurna Ghosh ◽

Jinxin Huang ◽

...

Keyword(s):

Coal Dust ◽

Factorial Experiment ◽

Dust Suppression ◽

Suppression Efficiency

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Foam for coal dust suppression during underground coal mine tunneling

Tunnelling and Underground Space Technology ◽

10.1016/j.tust.2019.04.009 ◽

2019 ◽

Vol 89 ◽

pp. 170-178 ◽

Cited By ~ 9

Author(s):

Qing Guo ◽

Wanxing Ren ◽

Jingtai Shi

Keyword(s):

Coal Mine ◽

Coal Dust ◽

Dust Suppression ◽

Underground Coal Mine

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Development of Environmental Friendly Dust Suppressant Based on the Modification of Soybean Protein Isolate

Processes ◽

10.3390/pr7030165 ◽

2019 ◽

Vol 7 (3) ◽

pp. 165 ◽

Cited By ~ 35

Author(s):

Hu Jin ◽

Wen Nie ◽

Yansong Zhang ◽

Hongkun Wang ◽

Haihan Zhang ◽

...

Keyword(s):

Water Retention ◽

Soybean Protein ◽

Coal Dust ◽

Sodium Dodecyl ◽

Environmentally Friendly ◽

Protein Isolate ◽

Dust Particles ◽

Dust Suppression ◽

Soybean Protein Isolate ◽

Coal Particles

Aiming to further improve the dust suppression performance of the dust suppressant, the present study independently develops a new type of biodegradable environmentally-friendly dust suppressant. Specifically, the naturally occurring biodegradable soybean protein isolate (SPI) is selected as the main material, which is subject to an anionic surfactant, i.e., sodium dodecyl sulfonate (SDS) for modification with the presence of additives including carboxymethylcellulose sodium and methanesiliconic acid sodium. As a result, the SDS-SPI cementing dust suppressant is produced. The present study experimentally tests solutions with eight different dust suppressant concentrations under the same experimental condition, so as to evaluate their dust suppression performances. Key metrics considered include water retention capability, cementing power and dust suppression efficiency. The optimal concentration of dust suppressant solution is determined by collectively comparing these metrics. The experiments indicate that the optimal dust suppressant concentration is 3%, at which level the newly developed environmentally-friendly dust suppressant solution exhibits a decent dust suppression characteristic, with the water retention power reaching its peak level, and the corresponding viscosity being 12.96 mPa·s. This performance can generally meet the requirements imposed by coal mines. The peak efficiency of dust suppression can reach 92.13%. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to analyze the dust suppression mechanism of the developed dust suppressant. It was observed that a dense hardened shell formed on the surface of the pulverized coal particles sprayed with the dust suppressant. There is strong cementation between coal dust particles, and the cementation effect is better. This can effectively inhibit the re-entrainment of coal dust and reduce environmental pollution.

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