Hydroprocessing ULSD Process by ExxonMobil

Application: A versatile family of ExxonMobil Research and Engineering Co. (EMRE) process technologies and catalysts are used to meet all current and possible future premium diesel requirements.

ULSD HDS—Ultra-deep hydrodesulfurization process to produce distillate products with sulfur levels below 10 wppm.

HDHC—Heavy-distillate mild-hydrocracking process for the reduction of T90 and T95 boiling points, and high-level density reduction.

MAXSAT—High-activity aromatics saturation process for the selective reduction of polyaromatics under low pressure and temperature conditions.

CPI—Diesel cloud point improvement by selective normal paraffin hydrocracking (MDDW) or by paraffin isomerization dewaxing (MIDW).

Description: EMRE units combine the technologies listed above in low-cost integrated designs to achieve the necessary product uplift at minimum investment and operating cost. For ultra-low-sulfur-diesel hydrodesulfurization (ULSD HDS), a single-stage single-reactor process can be designed. A small cetane improvement, together with the reduction of polyaromatics to less than 11 wt.% or as low as 5 wt.%, can be economically achieved with proper specification of catalyst, hydrogen partial pressure, space velocity and the installation of high-performance Spider Vortex internals.

The addition of heavy-diesel hydrocracking (HDHC) function to the HDS reactor can achieve T95 boiling point reduction together with higher levels of density and aromatics reduction and greater cetane improvement.

When feedstock aromatics are very high, or very low aromatics in the product are desired, a second-stage aromatics saturation (MAXSAT) system is specified to avoid very high design pressures required for a single-step base-metal hydrotreating catalyst system. When the distillate product must also meet stringent fluidity specifications, EMRE can offer either paraffin isomerization dewaxing (MIDW) or selective normal paraffin cracking-based dewaxing technologies (MDDW). These can be closely integrated with ULSD HDS and other functions to achieve the full upgrading requirements.

The EMRE ULSD technologies are equally amenable to revamp or grassroots applications. EMRE has an alliance with Kellogg Brown & Root (KBR) to provide these technologies to refiners.

Licensor: ExxonMobil Research and Engineering Co.