# Packed Bed Pressure Drop

Estimates packed bed pressure drop based on Ergun equation along with minimum fluidization and maximum superficial velocity.

Packed Bed Data

Gas Data

Packed Column

Porosity

Ergun Equation

\displaystyle \displaystyle \frac{\Delta P}{L} = 150\frac{\mu_f V \left( 1 - \varepsilon \right)^2 }{\phi_s^2 D_p^2 \varepsilon^3} + 1.75\frac{\rho_f V^2 \left( 1 - \varepsilon \right) }{\phi_s D_p \varepsilon^3}

Minimum Fluidization Velocity, V_{mf}

At minimum fluidization, pressure drop across bed is balanced by effective weight of the particle.

\displaystyle \displaystyle \left( \rho_p -\rho_f \right)g = 150\frac{\mu_f V_{mf} \left( 1 - \varepsilon_{mf} \right) }{\phi_s^2 D_p^2 \varepsilon_{mf}^3} + 1.75\frac{\rho_f V_{mf}^2}{\phi_s D_p \varepsilon_{mf}^3}

Maximum Velocity, V_{max}

Beyond maximum superficial velocity, particles will be carried away by the gas and will leave at the bed exit.

\displaystyle \displaystyle V_{max} = \frac{g D_p^2 \left( \rho_p -\rho_f \right)}{18 \mu_f}

Plot for Pressure Drop, ΔP