Abstract: Aiming at the technical bottlenecks of a 2.0 Mt/a fixed-bed residue hydrotreating unit in a refinery, such as the need to reduce the residue blending ratio before cutting out the guard reactor and the significant fluctuation of bed temperature rise after the complete cut-out, an optimized process for partial cut - out of the guard reactor was studied and applied. Compared with the conventional complete cut-out process of the guard reactor, this method can maintain a higher residue blending ratio. At the same time, the fluctuation range of bed temperature rise can be controlled within ±5 °C, and the stability of process operation is significantly improved. The implementation of this method has successfully extended the operation cycle of the unit by about 3 months, providing an engineering solution for the long-period operation of fixed-bed residue hydrotreating units.

Key words: residue hydrogenation, guard reactor, partially cut out, long-term operation