Q&A

(2010) Question 85: What is the typical range that you employ for iron content on FCC equilibrium catalyst? What methods are available to determine how iron is accumulated on the catalyst surface? How does the distribution of iron on the catalyst surface impact the FCC operation, yield structure and emissions?

There are several methods available to quantify iron contamination on catalyst. Scanning Electron Microscopy (SEM) pictures are a valuable means to qualitatively assess iron laydown morphology on the catalyst particle.

(2010) Question 21: Silica uptake on gas oil and diesel hydrotreating units is an increasing problem. In your experience, what is the source of silica in these feeds? Do you have effective ways to manage this silica?

The main source of silicon in Hydrotreaters is polysiloxane compounds (such as polydimethylsiloxane) used to control foaming in delayed coker units. It has also been reported that indigenous silicon is present in some heavy oils.

(2010) Question 22: In your experience, how are ULSD units maximizing catalyst life/ cycle length? Do you use feedstock or catalyst analysis to locate sources of contaminants, especially arsenic?

Many factors impact the cycle length in a ULSD unit, and in order to ensure the longest possible cycle length in such units it is important to: Have an optimal flow distribution and gas mixing using latest generation reactor internals designed for the actual operating conditions. This is very important in order to ensure maximum catalyst utilization with no channeling in the catalyst bed.

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Q&A

(2010) Question 21: Silica uptake on gas oil and diesel hydrotreating units is an increasing problem. In your experience, what is the source of silica in these feeds? Do you have effective ways to manage this silica?

(2010) Question 22: In your experience, how are ULSD units maximizing catalyst life/ cycle length? Do you use feedstock or catalyst analysis to locate sources of contaminants, especially arsenic?