Packed absorbers at steady-state and unsteady-state operation

Abstract

On the basis of several field tests made on the packed absorber at the Zoller Gas Plant, located near Refugio, Texas, a mathematical model for describing such a process was developed. This model makes use of the concept of a mass-transfer section in order to represent a continuous separation process by a stage process. Several calculational procedures to be used for the prediction of product distributions as well as procedures to be used for the determination of vaporization efficiencies from field tests in existing absorbers were investigated. These procedures are highly recommended for use in the treatment of absorbers and strippers with plates as well as for packed absorbers. A procedure for predicting the transient behavior of an absorber was also developed. This procedure requires that the complete definition of the two feed streams and the pressure of the absorber be specified functions of time. The amount of vapor and liquid in each mass-transfer section must also be specified. In addition to this procedure, a procedure for determining the vapor and liquid holdups from the results of an unsteady-state field test was developed. These procedures were tested by the use of data taken on the absorber at the Zoller Gas Plant. Transient conditions were achieved by creating an abrupt change in the flow rate of the lean oil to the absorber.