Absorption Towers
Absorption Towers are used widely for mass transfer unit operation such as purification, processing of materials etc in process industries like Chemical Process, Petroleum, and Pharmaceuticals etc. Tipo heat Exchangers can design and supply Absorption Towers as per process / client’s requirement.
The absorption of SO3 from the gas relies on equilibrium factors as described in the section Absorption and Stripping. There are many physical factors that affect the degree of absorption that will occur in a tower. One of the primary factors is the vapour pressure of sulphur trioxide/sulphuric acid above the acid.
Absorber towers operate in a relatively narrow range of concentration and temperature for effective absorption of SO3. This is apparent when you look at a plot of the total vapour pressure versus acid concentration curve. In a concentration range of 97.5% to 98.5% the equilibrium vapour pressure above sulphuric acid reaches a minimum. Operation in this acid concentration range will result in the maximum absorption of SO3.
The vapour pressure curves (better curve to follow) indicate that the lower the acid temperature, the lower the vapour pressure above the acid. This would imply that operating the absorber system at lower temperatures would result in better absorption, however, this is not the case. At lower temperatures other physical properties such as density and viscosity begin to affect the absorption process in a negative manner.
Industry practice is to operate the absorber system with acid inlet temperatures in the range of 65 to 85°C. In North America, plants operate at the higher end of the temperature range, nominally 80°C. In Europe, operation at the lower end of the temperature range is more typical.
Sailent Features:
1. Designed and Fabricated as per IS:2825 and ASME Sec VIII Div 1 & 2 Codes & Standards
2. Materials of Construction: SS304, SS304L, SS316, SS316L, Duplex Steel or Carbon Steel
3. Comprises of: Absorber Shell, Packing Support, Packing Material, Distribution Plate, Spray System, required Nozzles, Manholes and instrumentation etc
4. Packing – Pall Rings, Raxhig Rings, Intalox Saddles, Mellapack etc