A dimensionless model for predicting the mass‐transfer area of structured packing

The mass‐transfer area of nine structured packings was measured in a 0.427 m ID column via absorption of CO 2 from air into 0.1 kmol/m 3 NaOH. The mass‐transfer area was most strongly related to the specific area (125–500 m 2 /m 3 ), and liquid load (2.5–75 m 3 /m 2 ·h). Surface tension (30–72 mN/m) had a weaker but significant effect. Gas velocity (0.6–2.3 m/s), liquid viscosity (1–15 mPa·s), and flow channel configuration had essentially no impact on the mass‐transfer area. Surface texture (embossing) increased the effective area by 10% at most. The ratio of mass‐transfer area to specific area ( a e / a p ) was correlated within the limits of ±13% for the entire experimental database aₑ aₚ = 1.34 [ ( ρ L σ )g1/3 ( Q Lₚ )4/3 ]\,0.116 .