Experimental and simulation studies on the improvement of coal dust pollution by an aqueous solution of sodium α-alkenylsulfonate and amino acid-based surfactants.

The use of surfactants is crucial for the prevention and control of coal dust pollution in coal mining operation areas, yet there still exist many challenges in the control of coal dust pollution. In this paper, the green biomass-based amino acid surfactant sodium myristoyl glutamate (SMG) and the anionic surfactant sodium α-alkenyl sulfonate (AOS) were selected to investigate the improvement of coal dust wettability by single and binary solutions from the macroscopic and microscopic perspectives. Molecular simulations were used to reveal the microscopic mechanism of the wettability of coal dust by the different solutions.

CFD-based simulation study of dust transport law and air age in tunnel under different ventilation methods.

To solve the problem of high-concentration dust pollution in a bored tunnel, we conducted a simulation study on the dust transport law and air age of the wind flow in a bored tunnel under different ventilation methods. Air age was innovatively introduced as an index for evaluating tunnel air quality. The results show that dust pollution is serious under conditions of press-in ventilation, which is unfavorable to personnel operations.

Study on PM diffusion and distribution of trackless rubber-tyred vehicle under different driving conditions in underground coal mining environment.

Particulate matter (PM) is one of the most harmful exhaust pollutants to human health. In this study, the PM diffusion and distribution emitted by trackless rubber-tyred vehicle under different driving conditions in coal mine were analyzed with numerical simulations and field measurements. The results show that when the vehicle velocity was constant, the PM concentration of the trackless rubber-tyred vehicle decreased with increasing distance from the exhaust pipe orifice.

Study of wetting and adsorption mechanism of mixed anionic-nonionic nonhomologous surfactants on coal dust based on intermolecular interactions.

The research found that mixed anionic-nonionic surfactants have synergistic wetting performance which can be added to the spray solution to greatly enhance the wettability to coal dust. In this study, based on the experiment data and some synergism parameters, and a 1:5 ratio of fatty alcohol polyoxyethylene ether sulphate (AES)-lauryl glucoside (APG) has the best synergism, resulting in a highly wettable dust suppressant. Additionally, the wetting processes of different dust suppressant on coal were comparatively simulated by molecular dynamics.

Development and characterization of a high efficiency bio-based rhamnolipid compound dust suppressant for coal dust pollution control.

Surfactants make a significant contribution to the suppression of coal dust fly in underground coal mines, but are hazardous to the environment and human health. It is therefore crucial to develop more environmentally friendly and efficient wetting agents using non-polluting eco-friendly surfactants. In this study, the wetting properties of the biosurfactant rhamnolipid were investigated and the rhamnolipid composite wetting agent (CS-A-S) was prepared by mixing design after preferring different surfactants by means of experiments and quantum mechanical simulations.

Study on the effect of Ce-Cu doping on Mn/γ-AlO catalyst for selective catalytic reduction in NO with NH.

A series of Mn/γ-AlO, Mn-Cu/γ-AlO, Mn-Ce/γ-AlO and Mn-Ce-Cu/γ-AlO catalysts were prepared by equal volume impregnation. The denitrification effects of the different catalysts were studied by activity measurement, X-ray diffraction, Brunauer, Emmett, and Teller surface area tests, Scanning electron microscopy, H-temperature programmed reduction and Fourier-transform infrared spectroscopy. The experimental results show that Ce and Cu are added to a Mn/γ-AlO catalyst as bimetallic additives, which weakens the interaction between Mn and the carrier, improves the dispersion of MnO on the surface of the carrier, improves the specific surface area of the catalyst, and improves the reducibility.

Numerical study on temporal and spatial distribution of particulate matter under multi-vehicle working conditions.

The high growth in the use of underground diesel vehicles has led to a large number of exhaust pollutants, especially particulate matter (PM), which is a serious threat to the lives and health of underground personnel. In this paper, based on numerical simulations and field measurements, the temporal and spatial distribution of PM in the exhaust of two vehicles and the impact on the health of underground personnel was analyzed. The results showed that in both conditions, the airflow velocity between two vehicles showed a zonal distribution, and there was an airflow vortex in the chamber under the interaction of the wind.

Carboxymethyl cellulose sodium gel: A modified material used to suppress coal dust pollution.

To reduce the environmental pollution caused by coal dust, a new type of dust inhibitor with a wide application range, high efficiency, and production simplicity was synthesized by modifying sodium carboxymethylcellulose (CMC-Na) with acrylamide (AM). Through molecular dynamics simulations and experiments, the surfactant composition and concentration were optimized. The experimental results showed that the graft copolymer of CMC-Na and AM (CMC-Na-co-AM) had more pores on the microscopic surface and a unique fiber network structure, which greatly increased its contact area with coal dust.

Simulation study of the mechanism of mesoscopic adsorption and the evolution of molecular dynamics of a surfactant/polymer composite on the surface of low rank coal.

In this paper, the head group, tail group, and main chain of a single type of surfactant were constructed by a mesoscopic simulation, and the interaction between the simulated surfactant and coal dust both on its own and in a composite with polyacrylamide (PAM) was studied. The molecular adsorption behavior of cetyltrimethylammonium chloride (CTAC) surfactant mixed in different ratios with PAM was also experimentally characterized. The results showed that.

The migration of CO and PM under different working conditions of trackless rubber-tyred vehicle and health risk assessment of underground personnel.

Trackless rubber-tyred vehicles are among the most widely used underground auxiliary transportation equipment in major coal mines at present. The migration of exhaust gas that threaten human health varies with the working conditions of trackless rubber-tyred vehicles. In order to better evaluate the health risks faced by underground personnel in the process of exhaust emission from underground diesel vehicles, in this paper, the migration of carbon monoxide (CO) and particulate matter (PM) emitted by trackless rubber-tyred vehicle under three working conditions was analyzed by using the method of CFD (Computational Fluid Dynamics) numerical simulation and field measurement.

Green surfactant-modified TiO nanoparticles doped with La-Cr bimetal for NO removal.

Cost-effective new environmental catalysts play a crucial role in purifying NO from exhaust gas of coal mine diesel vehicle. A new, environmentally friendly catalyst with high catalytic activity and good redox properties was prepared by a microwave-assisted sol-gel method using TiO nanoparticles as a catalyst, which were doped with La and Cr, and adding the surfactant dimethyldiallylammonium chloride (DMDAAC) as an organic modifier. The morphological characteristics, crystalline structure, functional groups, and elemental types of the catalyst were characterized, and the properties of the catalyst, such as redox ability and catalytic activity, were examined with H-temperature-programmed reduction experiments and activity tests.

Study of the microscopic mechanism of lauryl glucoside wetting coal dust: Environmental pollution prevention and control.

Molecular dynamics simulation combined with experimental methods were used to investigate the adsorption and wetting process of 25 lauryl glucoside (APG-12) molecules on coal molecules and in turn study the dust suppression mechanism by APG-12 at the molecular level. Through wetting experiments, our preliminary findings showed that APG-12 does have a certain wetting effect on coal dust. According to density functional theory in molecular dynamics simulations, the electrostatic potential and surface charge of the APG-12 and coal molecular models were analyzed to identify their nucleophilic and electrophilic regions, and illustrate the hydrogen bond adsorption mechanism.

Behavior of the particulate matter (PM) emitted by trackless rubber-tyred vehicle (TRTV) at an idle speed under different movement conditions and ventilation optimization.

The particulate matter (PM) emitted by a trackless rubber-tyred vehicle (TRTV) in coal mines can seriously threaten the health and safety of the exposed workers underground. In this paper, in order to effectively reduce the PM concentration and improve the underground working environment, a combination of numerical simulations and field measurements was adopted to study the migration distribution of the PM emitted by a TRTV at an idle speed for 60 s under different movement conditions, and the dilution effects of the ventilation rate on the PM. The results showed that under different movement conditions, the PM mainly moved along the floor of the roadway, but upward diffusion trends were shown overall, which meant that the chambers are in high-risk areas.