What considerations should be taken into account when adjusting the reaction pressure in practical operations?

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Reducing the reaction pressure is beneficial for the aromatization reaction while suppressing the cracking reaction； Conversely, increasing the reaction pressure will enhance hydrocracking and reduce aromatization. To obtain more of the target product, reducing the reaction pressure is a good approach. However, when the reforming catalyst operates at low pressures, the carbon deposition rate on the catalyst increases rapidly, which will severely affect its service life. To this end, any reforming unit must maintain an appropriate reaction pressure to sustain a certain hydrogen partial pressure and avoid an excessively high carbon deposition rate. In modern continuous reforming units, thanks to the use of bimetallic catalysts with enhanced carbon-bearing capacity, along with corresponding catalyst continuous regeneration facilities that allow the carbon buildup on the catalyst to be burned off while maintaining normal production, the reaction pressure can be reduced to ultra-low levels, with an average reaction pressure of 0.35 MPa. This results in a significant improvement in product yield and quality. However, for a specific industrial continuous reforming unit, since the catalyst type, the plant pressure level, and the coking capacity of the regeneration unit are already determined, the reaction pressure is usually also fixed and not adjusted. In actual industrial production, it is the pressure in the product separator that is controlled, rather than the reactor pressure; the reactor pressure changes with the system pressure drop. Therefore, the pressure in the separator cannot represent the reaction pressure. The separator pressure in this unit is controlled at 0.24 MPa, while the designed average reaction pressure is 0.35 MPa. Of course, increasing the purity of the recycled hydrogen or appropriately raising the hydrogen-to-oil ratio can also increase the hydrogen partial pressure.