Q&A

(2016) Question 25: For refinery complexes considering grassroots or brownfield expansion of gas oil conversion capacity, what are your typical capital expenditure (capex) costs and relative refinery margin improvement between FCC (fluid catalytic cracking) and hydrocracking? What are the key technology features that impact your economic decision? What are the crucial considerations that, if they include both technologies, to allow for future integration, especially around the changing gasoline/diese

In general, Marathon’s economic viewpoint is that hydrocrackers have better projected margins going forward than FCCUs, as they maximize higher valued ULSD over gasoline and have higher volume expansion (see Figure 1). This is driven by many factors mentioned in the primary response and is particularly attractive when ULSD is strong relative to gasoline and when natural gas or hydrogen) is inexpensive. Each company has a different viewpoint on this topic, so the opinion will vary somewhat across the industry.

(2019) Question 40: What rationale have you used to justify replacing the FCCU regenerator or reactor vessel?

What rationale have you used to justify replacing the FCCU regenerator or reactor vessel?

(2019) Question 41: How reliable are main air blower check valves?  What are some improved designs or some things to avoid?  Are there any alternatives?  If multiple branches, is there one check valve in the main branch or one check valve per branch, where is it located?  What is your maintenance or inspection best practices?

How reliable are main air blower check valves?  What are some improved designs or some things to avoid?  Are there any alternatives?  If multiple branches, is there one check valve in the main branch or one check valve per branch, where is it located?  What is your maintenance or inspection best practices?

(2019) Question 49: What are your reliable methods to monitor expansion joint temperature?  Are some joints more critical than others?  What temperature range is acceptable?  How do you increase or decrease temperatures if they are out of the desired range?

What are your reliable methods to monitor expansion joint temperature?  Are some joints more critical than others?  What temperature range is acceptable?  How do you increase or decrease temperatures if they are out of the desired range?

(2019) Question 51: What are some parameters that affect performance and reliability of FCC feed nozzles?  Can you describe any experiences with nozzle erosion inside the riser?  What about an external leak in the nozzle sleeve?

What are some parameters that affect performance and reliability of FCC feed nozzles?  Can you describe any experiences with nozzle erosion inside the riser?  What about an external leak in the nozzle sleeve?

(2019) Question 53: What are some of your industry practices for upgrading gas plant piping to post weld heat treat to manage carbonate cracking risk?  Please comment on methods such as requirement for new piping, systematic replacement of existing piping, risk-based replacement, or inspection based?

What are some of your industry practices for upgrading gas plant piping to post weld heat treat to manage carbonate cracking risk?  Please comment on methods such as requirement for new piping, systematic replacement of existing piping, risk-based replacement, or inspection based?

(2019) Question 8: Where is salt (NH4Cl or (NH4)2S) fouling most likely to occur? What are common practices for monitoring and mitigating?

ABIGAIL SLATER (HollyFrontier)
Salting typically occurs in the reactor effluent exchangers (shell and tube and fin fans), recycle and net gas compressors, and product stabilizer overhead system (top trays, overhead condenser, etc.). Common monitoring practices on exchangers and fin fans can be

(2019) Question 9: How do you track chloride in liquid/gas/LPG? What are your criteria for replacing adsorbent in chloride treaters?

DAVINDER MITTAL (HPCL Mittal Energy)
Chlorides have been a long standing issue in catalytic reformer operation. Until a few years ago, the focus on preventing operational problems from the chloride compounds in the catalytic reformer product stream was to remove HCl. More recently, a growing

(2019) Question 10: What causes metal-catalyzed coking (MCC) that obstructs catalyst circulation in CCR reformers? What actions do you take to mitigate MCC formation?

BILL KOSTKA (AXENS NORTH AMERICA)
Metal-catalyzed coke (MCC) formation typically occurs on 3d valence transition metals such as iron and nickel. Under CCR-like conditions of low hydrogen partial pressure (less than about 620 kpa), high temperature (more than about 480 °C) and low or stagnant flow

(2019) Question 11: Where are your liquid-phase chloride treaters installed for reforming units? What are the advantages of each location?

BILL KOSTKA (AXENS NORTH AMERICA)
Liquid-phase Cl treaters are typically used in three locations for reforming units.

Treating the unstabilzed reformate stream provides several advantages. The stream is heated upstream of the stabilizer column which ensures that any ammonium chloride is

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