Experimental investigation and simulation of the chemical absorption in a packed column for the system NH3–CO2–H2S–NaOH–H2O

A non-equilibrium heat and mass transfer model to describe the chemical absorption of ammonia, carbon dioxide and hydrogen sulfide in an aqueous solution containing sodium hydroxide and/or ammonia is introduced. The influence of chemical reactions on mass transfer in the electrolyte system is accounted for by enhancement factors. The pilot plant concept, as well as the applied experimental and analytical procedures to achieve experimental results for the validation of the model are presented. A comparison between the experimental data and the simulation results proves the predictivity of the presented mass transfer model. The discussion of the results leads to an optimum pH range for the operation of the given process.

[1]  W. Whitman,et al.  The two film theory of gas absorption , 1962 .

[2]  T. J. Edwards,et al.  Thermodynamics of aqueous solutions containing volatile weak electrolytes , 1975 .

[3]  C. Wilke,et al.  Correlation of diffusion coefficients in dilute solutions , 1955 .

[4]  R. Higbie,et al.  The Rate of Absorption of a Pure Gas into a Still Liquid during Short Periods of Exposure , 1935 .

[5]  W. B. Bloem,et al.  Improvement of a coke-oven-gas desulfurization process , 1990 .

[6]  L. Pearson,et al.  The kinetics of combination of carbon dioxide with ammonia , 1956 .

[7]  Gary T. Rochelle,et al.  Rate-based modeling of reactive absorption of CO2 and H2S into aqueous methyldiethanolamine , 1998 .

[8]  Ellen M. Pawlikowski,et al.  Phase equilibriums for aqueous solutions of ammonia and carbon dioxide , 1982 .

[9]  James R. Fair,et al.  Distillation columns containing structured packings: a comprehensive model for their performance. 1. Hydraulic models , 1993 .

[10]  Arvo Lannus,et al.  Gas‐Liquid Reactions , 1970 .

[11]  P. V. Danckwerts.  Significance of Liquid-Film Coefficients in Gas Absorption , 1951 .

[12]  G. Maurer.  On the Solubility of Volatile Weak Electrolytes in Aqueous Solutions , 1980 .

[13]  L. Pearson,et al.  The kinetics of combination of carbon dioxide with hydroxide ions , 1956 .

[14]  W. K. Lewis,et al.  The Evaporation of a Liquid Into a Gas , 1922, Transactions of the American Society of Mechanical Engineers.

[15]  E. V. Murphree.  Graphical Rectifying Column Calculations. , 1925 .

[16]  Eugeny Y. Kenig,et al.  Rigorous dynamic modelling of complex reactive absorption processes , 1999 .

[17]  James R. Fair,et al.  Distillation Columns Containing Structured Packings: A Comprehensive Model for Their Performance. 2. Mass-Transfer Model , 1996 .

[18]  B. Rumpf,et al.  Simultaneous solubility of ammonia and sulfur dioxide in water at temperatures from 313.15 K to 373.15 K and pressures up to 2.2 MPa , 1993 .

[19]  J. Zemaitis,et al.  Handbook of aqueous electrolyte thermodynamics , 1986 .

[20]  James R. Fair,et al.  Prediction of point efficiencies on sieve trays. 1. Binary systems , 1984 .

[21]  J. Giddings,et al.  NEW METHOD FOR PREDICTION OF BINARY GAS-PHASE DIFFUSION COEFFICIENTS , 1966 .

[22]  Dynamic and steady state simulation of coke oven gas purification , 1999 .

[23]  J. Giddings,et al.  A Comparison of Methods for Predicting Gaseous Diffusion Coefficients , 1965 .

[24]  Reinhard Billet,et al.  Packed Towers: In Processing and Environmental Technology , 1995 .

[25]  P. J. Essens,et al.  Desorption of volatile electrolytes in a tray column (sour water stripping) , 1988 .

[26]  T. J. Edwards,et al.  Thermodynamics of Vapor-Liquid Equilibria for the Ammonia-Water System , 1978 .

[27]  Dukman Lee,et al.  Dynamic simulation of the sour water stripping process and modified structure for effective pressure control , 2002 .

[28]  E. V. Murphree.  Rectifying Column Calculations. , 1925 .