Managing the Refiner's Need for Increasing Middle Distillate Yields with Improved Catalyst Technologies

摘要

With the continued interest in processing domestic crude sources, as well as utilizing opportunity feed sources, refiners have been exploring ways to maximize their middle distillate production. Several domestic feed sources have reduced the demand on the ULSD hydrotreater making it significantly easier to treat to ULSD; however, with the low cost of crude, other feed sources have begun to be an issue that was not previously considered. A critical element in all the approaches to increasing diesel yield is the proper design and selection of a catalyst system for the hydroprocessing unit. Improvements in catalytic solutions have made significant advances in allowing the hydrotreater or hydrocracker to increase middle distillate yield. This approach to increasing diesel yields requires a detailed understanding of feed and operating conditions such that the hydrotreater or hydrocracker can be operated at optimum conditions for the unit cycle and all of these have limits depending on the various feed properties. Challenges in terms of hydrogen consumption, yield shifts, changes in cycle life, and the chemistry involved will be discussed to provide some guidance and understanding in order to maintain product quality with existing assets and minimal investment. This paper summarizes the requirements to understand the various catalytic options and unit operations and to demonstrate that higher yields of middle distillate can be achieved with existing assets and minimal investment.