Some Fundamental Aspects of Urea Technology

CONTENTS:

I Introduction.

II A New Phase Model for the Ammonia-Water-Carbon Dioxide System at Equilibrium at Urea Synthesis Conditions.

– 1. Introduction.

– 2. Theoretical development of the ternary phase model.

– 3. Experimental.

– 4. Experimental results and discussion.

– 5. Further discussion and practical applications of the model.

III Some Thermodynamic Aspects of the Ammonia-Water-Carbon Dioxide System at Urea Synthesis Conditions.

– 1. Introduction.

– 2. Some general aspects of the model.

– 3. The calculation of the bubble-points.

– 4 Calculations of gas-liquid equilibrium values in the water-rich half of NH₃-H₂O-CO₂ system.

– 5. The effect of excess NH₃ and H₂O on the conversion in the liquid phase.

– 6. Concerning the conversion to urea in the liquid phase at high temperatures (T = 90-200^oC.).

– 7. Limitations of the model.

.

IV

– 1. Measurement of condensation points in a gaseous ammonia-carbon dioxide-water mixture.

– 2. Theory.

– 3. Experimental.

– 4. Results and discussion.

– 5. Possibilities for the calculation of dew-points.

– 6. Practical applications of the dew-point measurements.

V Corrosion in an NH₃-H₂O-CO₂ Gas Mixture at Urea Synthesis Conditions.

VI An HGRP Pilot Plant.

VII Trends in Urea Process Technology.

Appendix.

Acknowledgements

Discussion following presentation of paper

Ir S M Lemkowitz, Ir M G R T de Cooker and Prof. Drs P J van den Berg, Faculty of Chemical Engineering, University of Delft, Netherlands.

115 pages, 56 figures, 9 tables, 148 references.