Packed Towers

Refer to Fig.(1).

  • Flooding usually occurs at a pressure drop of 2–3 inches of water per foot of packed height.

  • Loading usually occurs at a pressure drop in the range of 0.5–1.0 inch of water per foot of height.

  • Packed columns are often designed to operate at their loading velocities; they often have their lowest HETP’s at such conditions.

  • Typical packing materials: Refer to Fig.(2)

  • Type of packing arrangements: structured, random packing. Refer to Fig.(3).

  • Redistributors:

    • Mal-distribution of the liquid may develop in very tall towers in which the height of packing is more than 3 times the tower diameter. For tall towers, therefore, packing may be divided into several sections with liquid redistributors between the section.

  • For packed towers, flooding determines the minimum possible diameter, and the usual design is for 50 to 70% of the flooding velocity.