Application: The Bechtel Hy-Finishing process is a specialized hydrotreating technology to remove impurities and improve the quality of paraffinic and naphthenic lubricating base oils. In the normal configuration, the hydrogen finishing unit is located in the processing scheme between the solvent extraction and solvent dewaxing units for a lube plant operating on an approved lube crude. In this application, the unit operates under mild hydrotreating conditions to improve color and stability, to reduce sulfur, nitrogen, oxygen and aromatics, and to remove metals.
Another application is Hy-Starting, which is a more severe hydrotreating process (higher pressure and lower space velocity) and upgrades distillates from lower-quality crudes. This unit is usually placed before solvent extraction in the processing sequence to upgrade distillate quality and, thus, improve extraction yields at the same raffinate quality.
Description: Hydrocarbon feed is mixed with hydrogen (recycle plus
makeup), preheated, and charged to a fixed-bed hydrotreating reactor (1). Reactor effluent is cooled in exchange with the mixed feed-hydrogen stream. Gas-liquid separation of the effluent occurs first in the hot separator (2) then in the cold separator (3). The hydrocarbon liquid stream from each of the two separators is sent to the product stripper (4) to remove the remaining gas and unstabilized distillate from the lube-oil product. The product is then dried in a vacuum flash (5). Gas from the cold separator is amine-scrubbed (6) to remove H2S before compression in the recycle hydrogen compressor (7).
Licensor: Bechtel Corp.