Absorption and stripping process

Khudenko B M, Garcia-Pastrana A (1987) Temperature influence on absorption and stripping processes, Water Science Technology 19 877-888. 

Definitions Gas absorption is a unit operation in which soluble components of a gas mixture are dissolved in a liquid. The inverse operation, called stripping or desorption, is employed when it is desired to transfer volatile components from a liquid mixture into a gas. Both absorption and stripping, in common with distillation (Sec. 13), make use oF special equipment for bringing gas and liquid phases into intimate contact. This section is concerned with the design of gas-liquid contacting equipment, as well as with the design of absorption and stripping processes. 

To perform a further detailed process calculation on this multi-component absorption and stripping process, vapor liquid equilibrium data for methane, hydrogen, and carbon monoxide is... 

In a binary mixture equilibrium stage, the vapor and liquid compositions are a function of only distribution coefficients and hence a function of only temperature if the pressure is held fixed (Equations 3.3 and 3.4). Thus, in a binary system, the phase compositions are independent of feed composition. If a third component is added to the mixture, the equilibrium vapor and liquid compositions are influenced by the amount and identity of the third component. This phenomenon is the basis of absorption and stripping processes. The following is a simple mathematical analysis of the effect of a third component on phase distribution. 

Some extraction systems are such that the solvent and diluent phases are almost completely immiscible in each other. Hence, separation yields an extract phase essentially free of diluent and a raffinate phase that is almost pure diluent. This greatly simplifies the characterization of the system. When partial miscibility for an extraction process is very low, the system may be considered immiscible and application of McCabe-Thiele analysis is appropriate. It is important to note that McCabe-Thiele analysis for immiscible extraction applies to a countercurrent cascade. The McCabe-Thiele analysis for immiscible extraction is analogous to the analysis for absorption and stripping processes. Consider the flow scheme shown in Figure 5.23,... 

Use the McCabe-Thiele graphical method to determine number of equilibrium stages and outlet concentrations for absorption and stripping processes. 

The McCabe-Thiele analysis can be used to model physical absorption and stripping processes that use equilibrium stages. 

Natural gas, after separation of the associated liquid (gas oil), contains moisture. If this gas is put into a pipeline for transportation over a long distance, the life of the pipeline reduces due to corrosion by the moisture. Therefore, the gas is dehydrated before it is put into a pipeline. Generally, triethylene glycol is used to dehydrate the gas in conventional absorption and stripping processes. Twister BV [67] developed a supersonic separator... 

When plotting y vs. a , Eq. (11-3) is an equilibrium curve and Eq. (11-2) is an operating line. The number of theoreticial contacts can be determined by a stepwise method such as that used for absorption and stripping processes (Figs. 22-9 and 22-10). However, the minimum amount... 

Kohl, Absorption and Stripping in Rousseau, Handbook of Separation Process Technology, Wiley, 1987. 

Edmister, W. C., Hydrocarbon Absorption and Fractionar tion Process Design Methods, Pet. Engr. May 1947-March 1949 and, Absorption and Stripping—Factor Functions for Distillation Calculations by Manual and Digital—Computer Methods. A.I.ChJE. foumal, V. 3, No. 2 p. 165 (1957). 

Though packed absorption and stripping columns can also be designed as staged process, it is usually more convenient to use the integrated form of the differential equations set up by considering the rates of mass transfer at a point in the column. The derivation of these equations is given in Volume 2, Chapter 12. 

Purification processes are used to remove impurities such as sulfiirs, mercury, gums and waxes. The processes include absorption and stripping, solvent extraction and thermal diffusion... 

Diffusion through a stagnant film, as in absorption or stripping processes involving the transfer of a single component between liquid and vapor phases. Since there is a concentration gradient... 

Operating conditions for the absorption and stripping towers are important design parameters for the process. Due to vapor pressure and entrainment, propane will be present in the effluent gas streams from both the absorber and stripper. Usually this quantity of propane is not recovered and is considered an economic loss. The amount of propane in the gas phase is mainly dependent on the operating temperature and pressure of the towers. 

In particular, liquid-liquid extractions, wastewater treatments, gas absorption and stripping, membrane, and osmotic distillation, are the processes more studied. For example, the VOCs removal, the extraction of aroma compounds and metal ions, the concentration of aqueous solutions, the acid-gases removal, the bubble-free oxygenation/ozonation, have been successfully carried out by using membrane contactors [1, 2]. 

Multiple equilibrium stage processes simulated in this program are distillation, absorption, and stripping. Both simple and reboiled absorbers are included, and multiple feed plus side-stream products are possible from the fractionators. Matrix- and short-cut-type solution methods are provided in separate subroutines. 

CHEMCALC 11. AMSIM Amine Gas Tiealing Pbnt Simulator Gulf Publishing Company, Book Division P.O. Box 2608 Houston, TX 77252 (713) 520-4444 Models processes for absorption and stripping of H2S and CO2 in a gas stream. For hydrocarbon gases, also calculates hydrocarbons absoibed and stripped. 

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