Dust Removal Fan Research Articles

Diffusion characteristics of coal dust associated with different ventilation methods in underground excavation tunnel

To further explore the dust diffusion behavior and percentage of different particle sizes under various ventilation methods and perfect the existing research, this work systematically investigated the space−time variation of airflow and dust under three ventilation modes and elaborated on the dust control mechanism and proportion of particle size. The results indicated that using the dust removal fan could reduce the spread of high concentration dust. With the increase in wind volume of the dust removal fan (Qe), dust removal efficiency increased from 34.8% to 74.6%. Meanwhile, the dust of small particle size spread with the airflow towards the rear of the excavation tunnel, but the vortex generated by the larger Qe made it challenge to discharge respiratory dust. The air curtain installation position was determined at 20 m, which restricted the high dust concentration within 10 m so that most of the coal dust was discharged from the exhaust duct. This technology effectively diminished the concentration of dust, resulting in the total dust removal efficiency increased to 89.8% and 98.5%. The results could provide theoretical guidance for dust control and removal strategies of coal mine excavation tunnels.

Study of highly efficient control and dust removal system for double-tunnel boring processes in coal mines

To reduce coal dust pollution during double-tunnel boring processes in coal mines, an efficient control and dust removal system has been established and studied by combining theoretical analysis, experimental investigations, numerical simulations, and on-site measurements. The self-developed new spiral air curtain generator can quickly form multiple axial and radial dust control air curtains that cover the entire tunnel section. When combined with a wet-type dust removal fan, they form an efficient dust control and elimination system for double-tunnel boring in coal mines. The airflow and dust control effects of the highly efficient dust control and removal system, single press-in ventilation, and ventilation with dust removal fans were compared. The results show that with the proposed system, the dust concentrations in the boring tunnel and supporting tunnel can be controlled within 18 and 15 m distances from the working face, respectively. The dust control efficiency is increased by 82 % and 85 %, respectively. Hence, the dust concentrations in the coal mine are effectively reduced.

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. Following the installation of an on-board dust-removal fan, an effective dust-control air curtain forms in the tunnel, and the high-concentration dust is essentially controlled within the range of Z = 13m from the working face. The dust concentration in the working area on the left side of the tunnel is CD < 200mg/m3, and the dust-control effect is obvious. At the same time, the air age on both sides of the tunnel is reduced by 35.5% following the use of the on-board dust-removal fan. Taking into account dust control by ventilation and dust removal by fan, spraying dust reduction measures are added, and we developed automated wind-mist synergistic wet high-frequency oscillation dust-capturing technology for tunnel boring. This could effectively improve the problem of high levels of coal dust pollution in tunnels.

Comparative study of dust pollution and air quality of tunnelling anchor integrated machine working face with different ventilation

To study the influence of the air volume of the dust removal fan on dust diffusion during the excavation process, in this study we selected a fully mechanized excavation face with an anchor-integrated tunneling machine for simulation research. We sought to determine the optimal dust removal air volume. ANSYS FLUENT software was used to simulate the working environment of the dust removal fan under different air volumes. Through analysis of the dust movement law of air flow, the dust accumulation position and state are observed. As the exhaust air volume continues to increasing, the same trend is seen with the increase in the wind speed in the tunnel, and dust accumulation and diffusion are effectively controlled. An analysis of temporal and spatial evolution of dust migration showed, that when the exhaust volume Qs reaches more than 300 m3/min, the dust accelerates to the rear of the roadway, and the change in dust distribution is no longer obvious. Considering the situation in the field, it was shown that the optimal exhaust volume was Qs = 300 m3/min. We also found that with increasing air extraction volume, the air-flow speed in the roadway accelerated, which strengthened the pollutant discharge capacity of the far-pressing-near-absorption (FPNA) ventilation system. Finally, field tests were performed to analyze and compare the simulated data with actual data. The deviation rate was < 15%, thus the reliability of the numerical simulation was verified. The research methods and conclusions of this study provide an important reference for the effective control of construction tunnel dust and cleaner production, the protection of tunnel workers’ health, and the optimization of tunnel ventilation systems.

Numerical analysis on pollution law for dust and diesel exhaust particles in multi-ventilation parameter environment of mechanized excavation face

In order to effectively purify the diesel particulate matter (DPM) emitted by the trackless rubber wheel car in coal mining under the premise of dust control. This paper comprehensively investigated the laws of dust and DPM diffusion under forced ventilation and mixed ventilation and under different air intake volumes of the dust removal fan Q and different distances between the extractive air duct outlet and the head L by means of CFD numerical simulation. The following conclusions were drawn. Under mixed ventilation (Q = 450 m3/min) dominated by forced ventilation, when L= 5 m, the overall control effects on low-concentration dust, high-concentration dust and DPM are the best, with the diffusion distances being 46 m, 62 m and 54 m. Under mixed ventilation (Q=750 m3/min) dominated by exhaust ventilation, when L= 5 m, the overall control effects on low-concentration dust, high-concentration dust and DPM are the best, with the diffusion distances being 23 m, 24 m and 39 m, respectively. Therefore, under the above two air volumes, when L= 5 m, the best control effects can be achieved on dust and DPM in the working face.

Study on Dust Diffusion Law and Application of Wet Vibrating Wire Dust Removal Fan in Fully Mechanized Excavation Face

Fully mechanized excavation face is the main place of dust generation in coal mines. Due to the huge dust production and long ventilation distance, the dust concentration is difficult to reach the safety standard. The purpose of this study is to improve the dust removal efficiency of 2410 roadway in Yuhua Coal Mine. Firstly, this paper carried out dust concentration and roadway wind speed measurement on the 2410 fully mechanized excavation face of Yuhua Coal Mine. According to the actual layout of fully mechanized excavation face, the geometric model is established. The distribution of wind field in fully mechanized excavation face is simulated and analyzed by Fluent software. The correctness and feasibility of the model and simulation method are verified by comparing the simulation results with the measured data. Then the paper studies the influence of the air duct outlet installation position on the airflow field and the dust distribution, and analyzes the dust removal effect of the existing wet vibrating wire dust collector dust removal system in Yuhua Coal Mine. The research conclusion is that the wet string vibration dedusting fan has remarkable dedusting effect, and the dedusting efficiency is the highest when the air duct is installed near 10 m from the working face.

Simulation analysis and engineering application of distribution characteristics about multi-stage atomization field for cutting dust in fully mechanized mining face

To improve the dust suppression efficiency of the external spray systems of shearers, a dust reduction method consisting of shearer external multi-stage atomization and dust removal fan was proposed. Computational fluid dynamics-based numerical simulation was combined with atomization experiments to analyze the migration and distribution of the cutting dust and multi-stage atomization field under airflow at the 2307 fully mechanized mining face of the Tangkou mine. The results show that with adding dust removal fan and multi-stage atomization points, the peak area of wind speed appeared on both sides of the shearer, and the wind speed was greater than 2.7 m/s, the dust concentration on the downside side of the shearer decreased, the spray coverage area increased significantly, and the droplet concentration at the shearer drum was the largest, exceeding 0.05 kg/m3. According to the research results, the multi-stage atomization arrangement of single-fluid water nozzles of shearer was put forward, and the field application was carried out. Compared with the engineering application results of the single-stage atomization dust suppression system, the total dust reduction rate of the synergistic effect of multi-stage atomization external spray with dust removal fan for the shearer is 87.12%, which is 38.59% higher than that of the conventional single-stage atomization dust suppression system.

Research on tunnel ventilation systems: Dust Diffusion and Pollution Behaviour by air curtains based on CFD technology and field measurement

In order to further improve an air curtain's dust suppression performance in tunnels, this paper made an in-depth analysis of the effects of an air curtain generator's radial and axial pressure airflow rate and a dust removal fan's exhaust airflow rate on the diffusion and pollution behaviors of dust. Through CFD Technology and field measurements, it can be observed that: when the air curtain generator's axial-to-radial pressure airflow rate ratio (Ra/r) varied within the range of 1/9–6/4, the diffusion distance of high-concentration dust (with a concentration over 10 mg/m3) decreased with the decrease of Ra/r; and when Ra/r = 1/9, the formed airflow curtains exhibited the most favorable dust suppression performance. In addition: when the dust removal fan's exhaust-to-pressure airflow rate ratio (Re/p) increased, the diffusion distance of high-concentration dust decreased; and when Re/p = 1.2, the dust produced could be suppressed effectively by the air curtains. Finally, field measurements reveal that when a dust removal fan with a Re/p of 1.2 and an air curtain generator with a Ra/r of 1/9 were used in combination, high-concentration dust can be controlled fully within a range of 5.49 m from the head-on section by the formed air curtains, and the average dust concentration in the region 5–50 m away from the head-on section in tunnel was reduced to 9.82 mg/m3; i.e., the excavator driver and workers can be protected effectively.

Research of Ventilation Dedusting Technology of Full Section and Rapid Excavation Working Face in Daliuta Coal Mine

According to potential safety hazards of unreasonable ventilation and overrun dust concentration caused by the high degree of mechanization and the quick tunneling speed in the “long-distance & full-section” working face used in Daliuta coal mine of Shenhua coal group corporation limited, this paper studied the FPNA (far pressing near absorption ventilation) ventilation dedusting technology to solve the problems. This technology includes measures of simulation analysis on dust distribution, reasonable selection of the dust removal fan, adopting dynamic hanging technology to extending blower to the front of tunneling working face, setting up dust preventing board in front of tunneling machine and dust suppression by spraying. Field practice shows that the average dust concentration of working face is reduced by more than 50%, and achieved good results. The improved ventilation dedusting technology has been promoted and applied in Shenhua coal group corporation limited.

The effects of the installation position of a multi-radial swirling air-curtain generator on dust diffusion and pollution rules in a fully-mechanized excavation face: A case study

A great number of dusts are produced in the fully-mechanized excavation face during coal-cutting process. In order to block the dusts within the unmanned operating zone in front of the roadheader driver, this study combined FLUENT numerical simulation and field measurement for examining the dust's diffusion and pollution rules when both multi-radial swirling air-curtain generator and wet dust removal fan were used in the fully-mechanized excavation face; moreover, dust suppression performances when the generator was 5–50 m away from the head-on section (i.e., Lg) in the excavation face were investigated in depth. According to numerical simulation results, when Lg was 5–20 m, the diffusion distance of high-concentration dusts (with a concentration over 10 mg/m3) first increased and then decreased as the generator moved further away from the head-on section; when Lg was 14.8 m, dust pollution and diffusion were most serious; When Lg was 30.3–38.4 m, dust was diffused to the back of the roadheader driver, i.e., dust's diffusion and pollution cannot be effectively blocked in head-on region; When Lg was 20–30.3 m and Lg was 38.4 m, the generated dusts in coal cutting were significantly blocked within the range 5.88 m away from the head-on section, thereby exhibiting favorable dust-suppression performances; in particular, when Lg was 25 m, optimal dust-suppression performance can be obtained. Finally, the accuracy of the present numerical simulation results was validated by field measurement results.

The Finite Element Modeling and Structure Analysis of Dust Removal Fan

This paper mainly discussed the process to create finite element model of Y4-68 fan,and also analysis the nature frequency and liner static stress.According to the analysis result to determine the optimized parameters,to prepare for the stage of optimization.

The Application of Nonlinear Modeling in the Fault Diagnosis of Fan

The fault diagnosis of the history, present situation and main trend is reviewed. Based on a comparison of the traditional remote monitoring and diagnosis system, provides the architecture of a remote monitoring and diagnosis system. The remote monitoring and fault diagnosis system architecture for two dust removal fan remote monitoring system, the related research and development of the function and fault diagnosis research of the monitoring system, through the remote monitoring and fault diagnosis system can understand two dust removal fan running status, ensure the wind machine running status in the design constraints. It is proposed based on a nonlinear autoregressive moving average model, tested the sunspot data, then the model is applied to fault diagnosis of fan, the experimental results show that, the linear model and the traditional prediction model, has the high prediction accuracy, a new method is proposed for the Metallurgic Fan Machinery Fault diagnosis.

Simulation of flow-field interior dust removal system at a transit point and the overall technology of dust removal

In order to make a reasonable dry-type dust removal plan of the coal transit spot in a coal washery, it is essential to install the dust removal fan and guide chute. By means of the numerical simulation, the pollution mechanism at a transit point and the flow-field interior dust removal system had been analyzed. The result shows that the dust pollution at transit spot is mainly cased by the joint effort of induced airflow and shock-wave. With the appropriate dust removal fan and the guide chute, will effectively eliminate the positive pressure by gave rise to by the impact of falling coal, also avoid the secondary pollution.