Q&A

(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.

(2010) Question 34: What has been the experience of refiners operating selective hydrotreating of FCC naphtha regarding gum formation potential of the low sulfur gasoline? Is gum inhibitor addition a recommended practice?

Gum potential exists with unsaturated hydrocarbons (olefins or diolefins) stored in refinery operations with oxygen as a free radical. Organic sulfur and nitrogen compounds remaining in FCC gasoline product can form gums in the presence of olefins and oxygen.

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Q&A

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

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

(2010) Question 34: What has been the experience of refiners operating selective hydrotreating of FCC naphtha regarding gum formation potential of the low sulfur gasoline? Is gum inhibitor addition a recommended practice?