Q&A

(2018) Question 49: As the demand for higher octane gasoline components increases and lobbying for a 95 RON gasoline standard continues, how are you adjusting your operations to meet the market demand? What FCC specific changes do you make to produce higher octane gasoline components?

Refiners are optimizing their gasoline blend components to maximize high octane components. Alkylate and reformate yields are becoming increasingly important, as well as minimizing low octane component yields. The emergence of tight oil feeds has created an increase in low octane natural gasoline and LPG saturate production.

(2018) Question 50: Butylene demand and prices in relation to other refined products reached a record level in 2017. What caused it and what can we do in the FCC to produce more butylenes?

Higher demand for butylene is result of octane shortage in the gasoline market stemming from several main causes.

(2018) Question 55: With new challenges presented by the Refinery Sector and Maintenance Venting Rules oil circuits are taking longer to prepare for maintenance; what successes and challenges have you had in staging shutdown operations to allow for safe entry to the FCC reactor/regenerator section prior to clearing other sections of the unit?

With new challenges presented by the Refinery Sector and Maintenance Venting Rules oil circuits are taking longer to prepare for maintenance; what successes and challenges have you had in staging shutdown operations to allow for safe entry to the FCC reactor/regenerator section prior to clearing other sections of the unit?

(2018) Question 56: Excluding nickel passivation. How does antimony use in the reactor riser impact the FCC operations and equipment?

Antimony functions by attaching to a fresh Nickel molecule in the FCC feed and preventing it from laying down on the surface of the catalyst. Efficiency of antimony in passivating Nickel and tendency to have side effects is highly dependent on the carrier and distribution method. Antimony can be water based or oil based, with oil-based antimony having a higher lay down efficiency (approx. 85% typical) as compared to water based (approx. 65%).

(2018) Question 57: How are you optimizing the use of wet gas scrubbers caustic use and SOx additives?

You can utilize a SOx additive in addition to a Wet Gas Scrubber system in order to reduce caustic consumption and minimize cost. Utilizing a SOx additive can be optimized by calculating the caustic savings + value of additional liquid sulfur produced - the cost of the Sox additive.

(2018) Question 36: How do you manage the potential negative impacts of H2S Scavengers in imported coker feed?

How do you manage the potential negative impacts of H2S Scavengers in imported coker feed?

(2018) Question 37: Do you extend the time between de-coking the furnace by cutting coil outlet temperature or cutting furnace charge? How often are spallings done in coker furnaces? What is the temperature recovery after spalling?

Heater fouling is dependent on several variables that include the process film temperature, residence time at temperature and coke precursor concentration. I like to target a coke drum outlet temperature of 825°F before quench injection, which normally requires a Coker heater outlet temperature of 925°F.

(2018) Question 38: How does coke morphology vary with changes in feed quality? What feed tests do you require to quantify the impact on coke quality?

Predicting coke morphology from feed properties has not been 100% successful as the Coker operating conditions can make a difference if the feed is close to the shot coke vs. sponge coke threshold. The traditional approach uses the asphaltene content of the feed divided by the concarbon value of the feed.

(2018) Question 39: What operating conditions increase the generation of coke fines? What reliability issues do you associate with increased fines production?

Coke fine generation is really a function of the coke cutting process. Feed stock and coke drum operations during the actual drum fill cycle have very little to nothing to do with the generation of coke fines.

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