Upgrading of Coal Liquids. Interim Report: Hydrocracking of H-Coal Process Derived Gas Oils

摘要

The objective of this work was to evaluate, by bench scale continuous tests, the applicability of commercial UOP hydrocracking processes to conversion of H-Coal atmospheric still bottoms. Commercial catalysts were used. Process conditions were within commercial ranges. Relative to conditions specified in a base case for hydrocracking Arabian gas oil, the pressures used ranged from 500 psig lower to 500 psig higher. Temperatures were generally within 20 exp 0 C of base. Space velocities varied from one quarter of base up to base value. Catalysts, process conditions, and reactor sequences were varied to produce either gasoline, or environmentally acceptable No. 2 fuel oil. The H-Coal atmospheric bottoms were hydrotreated in one stage to give a low nitrogen, low sulfur fuel oil at 80% yield. Complete conversion to 600 exp 0 F exp - distillate was achieved by processing the heavy ends in a second hydrocracking stage. Conversion of the H-Coal atmospheric bottoms to gasoline was carried out in two stages. The second stage comprised either a single hydrocracking reactor or two reactors in series flow. The latter arrangement yielded, under the process conditions employed, 98 volume percent of 93 octane C sub 5+ gasoline, plus 28 volume percent of butanes. Hydrogen consumption was high, close to 4000 SCF/B for gasoline production and 1600 SCF/B for fuel oil production. This is a consequence of the aromaticity (85 volume percent) of the H-Coal atmospheric bottoms, as well as the high level of heterocyclic structures containing nitrogen, sulfur, and oxygen, which must be removed. In the gasoline case, about a half of this hydrogen can be recovered by steam reforming the light gases (C sub 1 -C sub 3 ) produced, and reformingthe hydrocracked gasoline. Including butanes in the steam reformer feed should result in hydrogen balance. (ERA citation 04:054048)