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(2013) Question 99: Tight oil-derived FCC feeds are known to contain high levels of contaminant iron (Fe) and calcium (Ca). What catalyst design features are important for minimizing their effects? What level of these contaminants can be tolerated? What lab procedures can accurately simulate Fe and Ca contamination?

There are a lot of parts to this question, so I will respond to them independently. One of the catalyst design features that is important in any kind of feed, when you are going to get high iron and high calcium, is in the porosity. We talked a little before about how these contaminant metals tend to form these eutectics which can melt the surface of the catalyst and close off the pores.
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(2013) Question 100: What specific changes in yields and product qualities might be expected when processing large percentages of tight oil-derived feeds? What operational changes can be made to address any problems created by these effects?

We are currently running varying degrees of tight oil at the majority or our refineries. At the refineries that are running a larger percentage of tight oil, the largest field impacts we have identified have been the shift to lighter products. At the same time, it insignificantly increased volume gains and significantly decreased slurry yield.
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(2017) Question 28: Under what conditions will you strip sulfur from hydrotreating/hydrocracking catalysts?

Base-metal hydrotreating and hydrocracking catalysts are susceptible to sulfur stripping at high temperature in the presence of flowing hydrogen and in the absence of H2S. For that reason, we advise unit operators to avoid prolonged exposure of sulfided catalysts to flowing hydrogen at temperatures exceeding 500°F if the H2S content of the hydrogen is below 50 ppmv (parts per million by volume).
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(2017) Question 30: What are common mechanical defects that occur to the weld overlay material in hydroprocessing reactors? What are the most common locations for defects, and does the location play a factor in the mechanical integrity of the equipment? How do you detect and repair the defects? How often do you conduct Remaining Life Analysis (RLA) and/or Fit For Service (FFS) Assessment on critical equipment?

The common mechanical defects that occur are disbonding and cracking. Non-vanadium-modified 2¼ Cr-1 Mo material is more susceptible to disbonding than vanadium-modified 2¼ Cr-1 Mo-V material. V-modified 2¼ Cr-1 Mo has a much higher solubility of hydrogen compared to conventional 2¼ Cr -1 Mo. 
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(2017) Question 31: What are the potential impacts to hydrocracking units [i.e., deactivation rate, HPNA (heavy polynuclear aromatics) formation, etc.] as heavy coker gasoil (HCGO) rate/endpoint are increased?

Processing heavier and cracked feedstocks poses many challenges to the hydrocracking unit. Thermally-cracked feedstock such as HCGO, apart from being unsaturated, has relatively lower API, higher sulfur, and nitrogen content, higher proportion of C7 insoluble, and Conradson carbon residue (CCR). An increase in the HCGO distillation endpoint results in a significant increase in the proportion of polynuclear aromatics (PNA) and asphaltenes, both of which are coke precursors, which results in an exponential increase in catalyst deactivation rates. 
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(2010) Question 71: For the main column, "tri lines" can be utilized to monitor bottoms level. When other level instruments are being verified or have failed, what are the best operating and safety practices being employed to verify the level? What do refiners use to monitor and control level in the bottom of the main column?

For the main column, "tri lines" can be utilized to monitor bottoms level. When other level instruments are being verified or have failed, what are the best operating and safety practices being employed to verify the level? What do refiners use to monitor and control level in the bottom of the main column?
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(2010) Question 72: With advance controls on the FCCU and gas plants, what are refiners doing to train new operators and keep their experienced operators sharp and ready to handle FCCU upsets and emergencies? Are refiners using simulators to help with the training and retraining?

Sunoco employs Dynamic Matrix Control (DMC) on all the FCC gas plants and DMC on reactor and regenerator systems. One FCC has a complete process training simulator, and we are in the process of installing simulators on all of our FCC’s.
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