DESCRIPTION

Technical Description

Packed columns have a variety of uses in process engineering, waste water and air purification and in biotechnical systems. For example, in an adsorption column the two substances can be brought into close contact using the packing. When used as a fixed bed reactor, the packing carries the catalyst necessary for the reaction. Packing is available in the widest variety of shapes and materials.

Observing the desired flow conditions is vital for proper functioning. Wetting, contact time and flow resistance play a key role. These packed column properties can be studied with the HM 136 trainer, and important phenomena such as the wall effect or the flooding point can be demonstrated.

The central element of the trainer is the transparent packed column. The pressures in the top, middle and bottom of the column are measured, so that the pressure losses in the fixed bed can be determined. The column can be operated with air or water. When operating with water, the direction of flow can be changed, so that even a fully flooded column can be studied, such as in a fixed bed reactor. Operating the column with air and water in counterflow simulates the application as an absorption column. The packed bed is interchangeable, so that a laboratory's own packing can also be tried out.

The experimental unit has its own air and water supply. The closed water circuit consists of storage tank, pump, flow meter and valve. The air supply includes a compressor with flow meter and valve.

The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.

Learning Objectives / Experiments

- function of a packed column 
- record pressure loss characteristic curve
- compare operating modes 
  * with water 
  * with air 
  * air/water counterflow mode
- demonstration of 
  * wall effect
  * stream formation
  * loading point 
  * flooding point