Guard of Catalysts for the Hydrotreating of Oil Fractions to Remove Solid Particles: Experimental Studies and Calculations

The efficiency of trapping of solid microparticles contained in diesel fuel by a package loading of catalysts, which is a counterpart of an industrial package of guard bed hydroprocessing catalysts, is studied. The package of catalysts consists of catalyst pellets graded with respect to shape and size: segmented rings, hollow cylinders of two standard sizes, and pellets with a trilobe-shaped cross section. The tests are conducted in a trickle flow mode using a constant ensemble of microparticles—iron scale with a size of 5–150 µm—at the inlet of the package loading. It is found that the penetration coefficient of the package loading of guard bed catalysts does not change significantly (K ≈ 0.985) during the test. At the same time, the pressure drop across the 17-cm-high guard bed catalyst package linearly increases from 220 to 408 Pa due to the trapping of solid microparticles by the catalyst pellets. The theoretical estimate of the initial pressure drop (228 Pa) agrees with the test data (220 Pa) with fairly high accuracy.