Pattern characterization concerning spatial and temporal evolution of dust pollution associated with two typical ventilation methods at fully mechanized excavation faces in rock tunnels

J of Applied Polymer Sci

et al. 2018

Self Cite

To mitigate the dust dispersion pollution in the open-pit coal mines, this study experimentally develops a novel environmentally friendly coal dust suppressant. The experiment uses naturally biodegradable soybean protein isolate (SPI) as the main material and utilizes anion surfactant sodium dodecyl sulfate (SDS) to modify SPI. In the carboxymethylcellulose sodium and sodium silicate and other auxiliary agents, this process produces gives rise to the SDS-SPI coal dust suppressant. Experimental characterization of the developed dust suppressant reveals that the viscosity of the 5% dust suppressant solution can reach 24.6 mPa s. Correspondingly, the compressive strength reaches 0.48 MPa, and the dust suppression efficiency can reach 93.47% with the presence of force 9 wind. Furthermore, this study uses Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) to analyze the dust suppression mechanism of the developed dust suppressant. It is observed that a layer of compact hardened shell is formed at the surface of the coal powder treated with the newly developed dust suppressant. Also, there exists a strong cementing effect among dust particles, yielding a decent cementing performance. Therefore, the present dust suppressant can effectively suppress dust dispersion in the open-pit coal mines, allowing a mitigation of the environmental pollution.

Section: Introductionmentioning

confidence: 99%

Preparation and characterization of a novel environmentally friendly coal dust suppressant

Nie

J of Applied Polymer Sci

et al. 2018

Self Cite

“…Only the dynamic properties of the flow field are considered, not the thermodynamic properties, so the energy equation is omitted. The governing equations including the continuity equation and the kinetic equation of the fluid under the cartesian coordinate system can be written as [37][38][39][40][41]:…”

Section: Mathematical Model Of a Negative Pressure Flow Field In The mentioning

confidence: 99%

Experimental Research and Numerical Simulation of Ejector Precipitator in a Fully Mechanized Mining Face

Zhai

et al. 2020

Arab J Sci Eng

In order to effectively reduce the coal dust concentration in a fully mechanized mining face, this research used laboratory experiment, numerical simulation, and field test to conduct an in-depth exploration of the ejector precipitator installed at the low-level caving coal hydraulic support. Firstly, through the experimental platform in the laboratory, the dust removal effect of the nozzle with different structural parameters was tested, and the 3D particle dynamic analyzer was adopted to verify its atomization characteristics; then, the structural parameters corresponding to the nozzle in the best test results were obtained. Secondly, by using Fluent, the negative pressure flow field in the ejector barrel was numerically simulated. The results indicated that when the pressure of supply water was 12 MPa, the negative pressure value formed in the flow field was the lowest and the inspiratory velocity was the largest, which was conducive to dust removal. Finally, the tests of liquid–gas ratio and dust removal ratio were carried out in a fully mechanized mining face. The results showed that when the nozzle specification recommended by the experiment and the pressure of supply water recommended by the numerical simulation were used, the removal ratios of the total coal dust and the respirable coal dust were 89.5% and 91.0%, respectively, at the measuring point of the highest coal dust concentration. It indicates that the ejector precipitator has a good application effect in reducing the coal dust concentration in a fully mechanized mining face and improving the work environment of coal mine workers.

“…This process may result in the formation of protein-surfactant (SDS-SPI) complex chemicals. In addition, loose connections between domains are compromised, resulting in a decrease in the molecular weight of the protein, which can be enhanced if it occurs within a certain range [76][77][78][79][80][81][82]. At the same time, comparing the results before and after the modification, it was found that the modified SDS-SPI moved to the left at the absorption peaks of 3377.33 cm −1 , 2800 cm −1 and 1393.1 cm −1 during the strengthening process.…”

Section: Infrared Spectra Testsmentioning

confidence: 99%

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

Nie

et al. 2019

Processes

Self Cite

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.