A Dynamic Study on the Sulfuric Acid Distillation Column for VHTR-assisted Hydrogen Production Systems

摘要

The sulfur-iodine (SI) cycle and the Westinghouse sulfur hybrid cycle coupled to a very high temperature gas-cooled reactor (VHTR) are well known as a feasible technology to produce hydrogen. The concentration of the sulfuric acid solution and its decomposition are essential parts in both cycles. In this paper, the thermophysical properties which are the boiling point, latent heat, and the partial pressures of water, sulfuric acid, and sulfur trioxide have been correlated as a function of the sulfuric acid concentration for the H_(2)SO_(4) and H_(2)O binary chemical system, based on the data in Perry's chemical engineers' hand book and other experimental data. By using these thermophysical correlations, a dynamic analysis of a sulfuric acid distillation column has been performed to establish the column's design requirements and its optimum operation condition. From the results of the dynamic analysis, an optimized column system is anticipated for a distillation column equipped with 2 ideal plates and a 2nd plate feeding system from the bottom plate. The effects of the hold-up of the reboiler and the reflux ratio from the top product stream on the elapsing time when the system progresses toward a steady state have been analyzed.