A topic that frequently comes up in consultation is how to posture a hydrotreater or hydrocracker when a short, temporary shutdown is needed (with no catalyst change). These short outages can last from a few hours to a few weeks and sometimes, rarely, a few months. Often, the biggest choice in how to posture a […]

A quantitative method for selecting emergency actions could prevent hydrocracker reactor temperature excursion and runaway while avoiding flaring. Recently published article in PTQ Q3 2023 Issue (digitalrefining.com). An excerpt from the article is below… Refiners use multiple emergency actions to react to a reactor temperature excursion or reactor runaway in a hydrocracking unit. Automatic depressuring […]

I had multiple requests to discuss how to evaluate purchased feedstocks for hydroprocessing units.  As always, I’ll present some ideas and welcome further comments and thoughts. Jack be nimble, Jack be quick! In my background, the question of whether to purchase a feedstock for a hydroprocessing unit comes up with very little notice and sometimes […]

This is the third of 3 articles discussing relief issues for Hydroprocessing Units. Last month we discussed Separator Blow-through. As discussed, the five main lessons from that article are: Relief valves on low-pressure separators must be designed for vapor blow-through The design vapor blow-through rate must consider all potentially open level-control valves and bypass valves […]

Article appears in the March/April 2023 issue of Inspectioneering Journal Introduction Fluid catalytic cracking units (FCCUs) have been fundamental to refinery operations and economics for many decades, with the very oldest operating units achieving 70 years of service. With no new refineries on the horizon for the United States and operating demands changing, maintaining these […]

This is the 2nd of 3 articles discussing relief issues for Hydroprocessing units. Last month, we discussed backflow prevention (CLICK HERE for 1st article). As a reminder, the three main lessons from that article are: Backflow protection must be provided on low-pressure to high-pressure interfaces including feed streams, wash water streams, and lean amine streams […]

Over the next few months I will cover relief issues for Hydrotreaters and Hydrocrackers. This topic will be the subject of an AFPM Safety Bulletin to be released in 2Q, 2023. Relief design and operation for hydroprocessing units has unique requirements compared to other refinery units because of the high-pressure-to-low-pressure interfaces.  The trick is to […]

CLICK HERE to view Part 1 of this series Tenets of Catalyst Selection I have had several suggestions to write about catalyst selection. This is a popular topic in many journals and blogs with some authors taking controversial stands on several issues.  I thought I would approach the subject by describing the important tenets that […]

Reactor Runaways – Automatic Depressuring or Manual Depressuring? Recently, I have had several discussions and inquiries regarding reactor runaway events and whether automatic depressuring systems are needed for hydroprocessing units. Short Answer ALL Hydrocrackers should have an Automatic Depressuring System Other units that use catalysts with high activation energy should consider an Automatic Depressuring System […]

Most of the people that have worked around refineries for some time, feel that they have mastered the basics of the major refining technologies and feel that they have some knowledge of the main strengths and vulnerabilities of those technologies.  In this blog, I’d hope to go beyond the basics and provide a deeper knowledge […]