(239c) Transfer Chute Design Considerations for Dust Control Using Computational Fluid Dynamics (CFD)

Dust emission from belt conveyor transfer chutes is one of the major sources of fugitive dust in material handling plants. Based on the authors’ previous studies, dust emission from bulk material transfer chutes can be qualitatively predicted using Computational Fluid Dynamics (CFD) with a two-phase three-dimensional Euler-Euler model. Among the transfer chute configurations investigated in previous studies, stilling chambers show benefits in terms of minimizing fugitive dust emissions compared to conventional designs. Furthermore, stilling chambers are a more suitable option to retrofit to existing chute installations than other options investigated, such as restrictor plates, etc. This study focuses on the optimal design of a stilling chamber using the two-phase three-dimensional Euler-Euler model. Typical design parameters that will be investigated include; the volume of the stilling chamber, the length of the stilling chamber and the pattern of the baffles inside the enclosure. In addition, the application of a self-adjusting flap at the outlet of the chute, both with and without the stilling chamber fitted, is also investigated. The results show that: the stilling chamber reduces likely dust emission from the chute; increasing the height of the stilling chamber does not necessarily reduce dust generation; extending the length of the stilling chamber can reduce likely dust emission, however it is not proportional to the length of the stilling chamber; the location of the baffles within the stilling chamber have a significant impact on likely dust emission; and, the self-adjusting flap has a significant effect on controlling the dust, especially in a chute without a stilling chamber.