![Sample our Engineering & Technology journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5933/TOC-Subject-Sample-2021-Engineering-Tech.jpg"})
ABSTRACT
Coke-making plants threaten the health of workers seriously. During the charge of coke furnace by the charging machine, the coal particles are released which resulted in spreading a large amount of coal, endanger workers’ health, and affect the air quality index. In this study, numerical simulation of a gravitational settling chamber was carried out, and modifications were applied in the chamber baffle arrangements to improve its efficiency. A combined Eluerian–Lagrangian approach was used to model the turbulent air flow and particle phase. The modification of the chamber was performed adding vertical, angled, and curved baffles which significantly improved the overall chamber efficiency in all particle size ranges. Results showed that the chamber removal efficiency for particles larger than 100 µm is about 50% in case of a chamber with no baffle inside. This efficiency approached 100% when a vertical baffle with optimum length is added in the middle of the chamber. The results also showed that the application of curved baffles with a tilted flat baffle with 30° angle is the best arrangement for collecting particles larger than 50 µm with an overall removal efficiency of 75%. This optimized arrangement helps to remove particles of smaller size without using high-speed separators. This study also showed that the inlet velocity of the chamber has a significant effect on the mean particle removal efficiency, and lowering the velocity resulted in a higher removal efficiency in all the studied cases.
Nomenclature
| Cc | = | slip correction factor |
| dp | = | particle diameter, m |
| FD | = | drag force |
| g | = | gravitational acceleration, m/s2 |
| Gk | = | production term of k equation |
| k | = | fluctuation kinetic energy, kg/ms1 |
| = | mean pressure, Pa | |
| Rep | = | particle Reynolds number |
| t | = | time, s |
| u | = | velocity, m/s1 |
| uˊ | = | fluctuating velocity component, m/s1 |
| = | time average velocity in axial direction, m/s1 | |
| x | = | axis, m |
Greek letters
| δij | = | Kronecker factor |
| ε | = | turbulence dissipation rate |
| λ | = | the mean free path of gas molecules, μm |
| μ | = | dynamic viscosity of air, Pa s |
| μt | = | the turbulent dynamics viscosity, Pa s |
| ν | = | kinematic viscosity of air, m2/s1 |
| ρ | = | density, kg/m3 |
Subscripts
| g | = | gas |
| i,j | = | direction |
| p | = | particle |