Coal dust suppression based on water mediums: A review of technologies and influencing factors

Fuel ◽  
2021 ◽  
Vol 302 ◽  
pp. 121196
Author(s):  
Qun Zhou ◽  
Botao Qin
Processes ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 165 ◽  
Author(s):  
Hu Jin ◽  
Wen Nie ◽  
Yansong Zhang ◽  
Hongkun Wang ◽  
Haihan Zhang ◽  
...  

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.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Youying Ma ◽  
Yuying Wang ◽  
Qingtao Zhang

Because of the unsatisfactory dust suppression efficiency, coal dust still threatens production safety and personnel health. In order to understand the influence of the chemical microstructures of the surfactant on the wetting ability and to facilitate the rapid selecting of surfactants with good wetting performances for specific coal dust, fatty acid methyl ester ethoxylate (FMEE), dodecyl dimethyl betaine (BS-12), sodium fatty acid polyoxyethylene ether carboxylate (AEC), and dodecyl dimethyl benzyl ammonium chloride (DDBAC) were selected in this paper to study the wetting ability of these four surfactants on the bituminous coal dust in Tongchuan, Shaanxi province of China. First, the main functional groups and carbon composition of the coal dust and surfactants were determined by Fourier transform infrared spectroscopy and carbon-13 nuclear magnetic resonance spectroscopy experiments. Second, the drop shape analysis system DSA100 was used to measure the equilibrium contact angle of the surfactant solution with a concentration of 0.06% on bituminous coal dust. The relationship between the chemical microstructures of surfactants and contact angles was analyzed, and the main influencing factors were obtained. The results showed that the contact angle of DDBAC on coal sample dust was the smallest. In addition, the contents of hydroxyl, aromatic ring carbon, unprotonated carbon, and bridged aromatic carbon in surfactants had significant linear correlations with wettability, and the increase of their contents would lead to the decrease of contact angle. According to the results of correlation analysis and curve fitting, the evaluation model of influencing factors on the wettability to bituminous coal dust was established.


2021 ◽  
pp. 129633
Author(s):  
Zidong Zhao ◽  
Ping Chang ◽  
Guang Xu ◽  
Apurna Ghosh ◽  
Danqi Li ◽  
...  

2011 ◽  
Vol 26 ◽  
pp. 1314-1321 ◽  
Author(s):  
Ding Cui ◽  
Nie Baisheng ◽  
Yang Hua ◽  
Dai Linchao ◽  
Zhao Caihong ◽  
...  

2021 ◽  
Author(s):  
Shuaifeng Wu ◽  
Hong Cai ◽  
Ran Wei ◽  
Jianzhang Xiao ◽  
Jun Yan ◽  
...  

Abstract Coal fly ash (CFA) that is discharged from coal-fired power plants has characteristics of fine particles, a small specific gravity and a large pore ratio. The dust suppression and strengthening of CFA is usually carried out by spraying water in the ash storage yard, but this practical approach is unsatisfactory. The strength of the CFA filling material affects the construction safety and operational safety of the ash dams. To carry out effective CFA material utilization and dust-pollution control, this paper applied the microbial-induced carbonate precipitation (MICP) method to enhance the strength of CFA under two curing conditions of natural evaporation (NE) and in a moisture cylinder (MC). The microbial-reaction mechanism, strengthening characteristics and influencing factors were studied. The results show that: 1) the calcium carbonate that is produced by microorganisms in the CFA is calcite, and the calcium-carbonate content increases from 7% to 18.9% and 15.3% under the MC and NE curing conditions, respectively; 2) MICP can improve the CFA strength, and the unconfined compressive strength can be increased by 6.55 times to 97.63 kPa under the MC curing conditions; 3) the solidification strength of CFA varies significantly with the concentration of CaCl2.2H2O and CH4N2O nutrients. The peak stress increases initially and then decreases with an increase in nutrient salt concentration. The optimum nutrient concentration was 0.5 mol/L and 1.0 mol/L for the MC and NE curing conditions, respectively; 4) calcium carbonate that was induced by microbial reaction can reduce the water loss in the ash specimen, and allow the ash surface to form a better water-retention effect, with good prospects for dust suppression.


Author(s):  
Chunyu Song ◽  
Yanyun Zhao ◽  
Weimin Cheng ◽  
Xiangming Hu ◽  
Shucang Zhu ◽  
...  
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