Numerical Modeling of Dust Lifting from a Complex-Geometry Industrial Stockpile

Abstract

This paper investigates the dust lifting phenomenon at the coal and iron ore stockpile at the Port of Koper, Slovenia. Dust lifting presents a serious environment and health hazard, thus the main objective of our study was to propose efficient measures for wind erosion reduction. A numerical model of the stockpile was created using the computational fluid dynamics (CFD) software. Wind velocity fields above the piles were calculated for the current stockpile layout and for several modified cases with rearranged piles and added porous barriers. Results from numerical modelling were used in the USEPA model to determine dust emission factors. Comparison of selected cases shows a positive, although limited effect of porous fences and barriers on reduction of local velocities and consequently, dust erosion rate. On the other hand, pile rearrangement has little effect and may not be practical for implementation. Realistic stockpile geometry with adjacent structures has shown to cause wind velocity distributions, which are not consistent with the most studied cases of regular pile shapes and layouts. The angle of incoming wind is a key factor influencing effectiveness of both solid and porous windbarriers. The proposed placement of porous barriers between the piles has shown to be effective in reducing wind exposure and dust emission. To maintain the dust emissions at an acceptably low level, other measures such as spraying with water and crust-forming liquids may still be necessary at higher wind velocities.

CFD Simulation Based Ventilation and Dust Reduction Strategy for Large Scale Enclosed Spaces in Open Pit Coal Mines—A Case of Coal Shed

“…Xiu et al [10,11] proposed a new semi-enclosed air curtain device for dust control to reduce dust pollution in a fully mechanized coal mine and conducted numerical simulations of the dust suppression effect. The results showed that the open-air curtain for dust control had an efficiency of 61.8% dust reduction and the diffusion of particles on the downwind side reduced the diffusion distance of ultrahigh concentration dust by about 35 m. Novak et al [12] calculated the flow velocity using Computational Fluid Dynamics software at a coal and iron ore dump. The results showed that the porous fence and barrier had a positive effect on reducing the local rate and reducing the dust erosion rate, that the actual accumulation geometry with adjacent structures would affect the wind velocity distribution, that the inlet angle was a key factor affecting the effectiveness of solid and porous wind barriers, and that the placement of porous barriers between the stockpiles could effectively reduce dust emissions.…”

Monitoring and Computation of the Volumes of Stockpiles of Bulk Material by Means of UAV Photogrammetric Surveying

“…A fundamental process in many activities is the management, handling and storage of bulk goods of various kinds. This can be seen in many business fields in which bulk materials constitute a cost, a resource, or is a phase of a process, e.g., in civil engineering [1], mining and extraction [2], industry [3], agriculture, food [4] and in the management of waste landfill and recycling sites [5].…”

An experimental and numerical study of the aeolian erosion of isolated and successive piles

“…Therefore, it is important to broaden the models application to more realistic situations. Several researchers have already performed this using both numerical (Computation Fluid Dynamics -CFD) and experimental (wind tunnel) approaches to investigate the physical phenomenon of wind erosion of granular materials beds and storage piles [8,16,17,22,24,25,32,37,39]. Badr and Harion [3] and Torano et al [30] numerically predicted the wind flow over isolated piles in different scenarios with various geometries and wind orientations and used the USEPA formulation for the emission factor to quantify particle emissions using the friction velocity previously calculated by CFD.…”