https://orcid.org/0000-0002-4547-2074
![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
ABSTRACT
Raw biodiesel usually contains a considerable amount of impurities that need to be separated. In this work, a 10-mm diameter Dorr-Oliver hydrocyclone was used to investigate the separate behavior of impurities from biodiesel prepared from waste cooking oil under different operational conditions. The experimental results showed a maximum impurity separation of 82.2% (v/v). The operational conditions including inlet mixture temperature, pressure drop across the hydrocyclone, and the percentage of inlet impurities were optimized using Taguchi method. Then, the hydrocyclone was modeled using CFD to optimize its dimensions. The experiments performed by the optimized hydrocyclone indicated an impurities separation of 90.76%.
Abbreviations
| Re | = | Reynolds number |
Nomenclature
| Flift | = | Lift force (N) |
| ΔP | = | Pressure drop across the hydrocyclone (kPa) |
| CL | = | Lift coefficient |
| C | = | Volumetric percentage of the inletimpurities (%) |
| Ftd | = | Turbulent dispersion force (N) |
| T | = | Temperature of the inletmixture (°C) |
| CTD | = | Turbulent dispersion coefficient |
| Dc | = | Diameter of cylindrical part (mm) |
| Xp | = | Interfacial area concentration (m2/m3) |
| w×h | = | Dimension of inletpart (mm2) |
| SRC | = | Coalescence source term |
| Do | = | Diameter of vortex finder (mm) |
| STI | = | Breakage source term |
| Du | = | Diameter of apex (mm) |
| fc | = | Frequency of droplet collision (1/s) |
| Lc | = | Length of cylindrical part (mm) |
| fb | = | Frequency of droplets collision and turbulent eddies (1/s) |
| Lp | = | Length of conical part (mm) |
| nd | = | Number of droplets |
| Lv | = | Length of vortex finder (mm) |
| ne | = | number of turbulent eddies |
| Rf | = | Flow ratio (%) |
| KC | = | Coefficient in IAC theory |
| η | = | Impurities recovery (%) |
| KB | = | Coefficient in IAC theory |
| Cvi | = | Impurities volume fraction in the inletflow (%) |
Greek letters
| Cvu | = | Impurities volume fraction in the outlet flow (%) |
| = | Volumetric fraction of continuous phase | |
| Qu | = | Total volumetric flow rate in the outlet (L/h) |
| = | Volumetric fraction of dispersed phase | |
| Qi | = | Total volumetric flow rate in the inlet(L/h) |
| = | Density of continuous phase (kg/m3) | |
| Uc | = | Velocity vector of continuous phase (m/s) |
| = | Density of dispersed phase (kg/m3) | |
| Ud | = | Velocity vector of dispersed phase (m/s) |
| = | Dynamic viscosity of continuous phase (kg/m.s) | |
| P | = | Pressure (kPa) |
| = | Dynamic viscosity of dispersed phase (kg/m.s) | |
| SM | = | Source term |
| = | Turbulent viscosity (kg/m.s) | |
| k | = | Turbulent kinetic energy (J) |
| ε | = | turbulent dissipation rate (J/s) |
| = | Strain tensor | |
| δk | = | Coefficient in RNG theory |
| Cμ | = | Coefficient in RNG theory |
| δε | = | Coefficient in RNG theory |
| C1ԑ | = | Coefficient in RNG theory |
| λC | = | Efficiency of coalescence from the collision |
| C2ԑ | = | Coefficient in RNG theory |
| λB | = | Efficiency of breakage from the impact |
| Fdrag | = | Drag force (N) |
| σ | = | Surface tension coefficient (N/m) |
| Urel | = | Relative velocity (m/s) |
| ϕ & Ψ | = | Shape factors |
| Ap | = | Area of particle image (mm2) |
| = | Solids pressure (Pa) | |
| CD | = | Drag coefficient |
| = | Granular temperature (m2/s2) |