The Gas Absorption Column, "CAG", is a scale unit designed to study hydrodynamic and absorption processes in packed columns. This system absorbs ammonia or CO2 from a mixture with air in a watery solution that descends along the column.
The main parts of the unit are:
- Packed column: it consists of a glass cylindrical column filled with Raschig rings.
- Liquid circuit (water): the liquid, that is stored in a PVC tank, is impelled towards the column by a pump. It feeds the column through its upper end using a glass diffusion shower. After crossing the column, the liquid is returned to the storage tank. The liquid flow that arrives to the column is measured with a flowmeter. In the storage tank, through aeration, the CO2 can be desorbed from the liquid previously filled in the column.
- Gas circuit (air and CO2): it consists of a CO2 and air (supplied by a blower) mixture current. Both gaseous currents are mixed, and later they enter the base of the column through a side inlet located below the bed level, so that the gaseous mixture is an homogeneous as possible. Both gas flows are measured by flowmeters.
- CO2 measuring system: it allows to determine the concentration of this gas in the currents originated from the upper and central parts of the column.