A new method for prediction of absorption/stripping factors

Abstract

Absorption and stripping are the unit operations which are widely used in the chemical processing industries. Many attempts have been made to define an average absorption factor method to short-cut the time consuming rigorous calculation procedures. The sole restriction of such a method is how well the average factor, as it is defined, will represent the absorption that actually occurs. The stripping operation is essentially the reverse of absorption and can be handled in a similar fashion. In this work, a simple predictive tool which is easier than existing approaches, less complicated with fewer computations is formulated to accurately predict the absorption efficiency as a function of absorption factor and number of absorber stages. The proposed predictive tool also can be used to determine the number of trays required for a given lean oil rate or to calculate recoveries with a given oil rate and tray count. The proposed method showed consistently accurate results for number of stages and absorption factors up to 20. Predictions showed an excellent agreement with the reported data with an average absolute deviation being less than 1%. The proposed method is superior owing to its accuracy and clear numerical background, wherein the relevant coefficients can be retuned quickly for various cases. This proposed simple-to-use approach can be of immense practical value for the engineers and scientists to have a quick check on absorption efficiency and estimating the trays required for a given lean oil rate or to calculate recoveries from a known oil rate and tray count at wide range of operating conditions without the necessity of any pilot plant set up and experimental runs. In particular process engineers would find the proposed approach to be user friendly involving transparent calculations with no complex expressions.