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(2017) Question 65: What variables impact feedstock atomization in the FCC riser? What steps do you take to optimize the feed and catalyst mixing for proper vaporization and catalytic reaction?

Feedstock atomization typically comes down to the design and reliability of the feed injector. Obtaining good atomization of the feed is important for optimizing the performance of any FCC. Feedstock atomization facilitates the rapid and efficient vaporization of the feed inside the riser, which can then initiate the cracking reactions.
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(2017) Question 66: In order to meet the pending MARPOL/IMO (International Convention for the Prevention of Pollution from Ships/International Maritime Organization) 0.5% sulfur fuel oil standards in 2020, what options do you have available to implement within FCC units to improve slurry quality, adjust yield, or find alternate dispositions, both within the overall facility and as a saleable product?

The FCC bottoms (decant oil or slurry bottoms), along with cycle oils, are often blended into internal and external fuel oils. With the lower sulfur regulation, high sulfur FCC bottoms will be a discounted stream based on sulfur content; and then further, on catalyst content. 
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(2017) Question 67: What strategies do you employ to optimize FCC plus hydrocracker operations? Do you process hydrocracker unconverted oil (UCO) in the FCC or FCC LCO/HCO in the hydrocracker?

FCC plus hydrocracker optimization covers several additional units including the reformers, H2 plants, sulfur plants, and LCO hydrotreaters (neat or mixed with other feeds). If the H2 plant and/or sulfur complex (including amine and sour water strippers) are constraining, then these constraints need to be considered in the optimization.
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(2017) Question 69: What operational or other changes prompt evaluation and optimization of standpipe aeration? What do you monitor to ensure the standpipes remain fluidized across a range of conditions?

Standpipe aeration is something which has been studied and reported on since the inception of cat cracking. Some standpipes require no attention and may not even have any aeration provisions provided. Others may be so sensitive to changing conditions that adjusting aeration is a daily action. Standpipe design is the most important factor. They tend to be very sensitive to changing direction, such as going from vertical to slanted. 
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(2017) Question 70: Electrostatic precipitator (ESP) fines handling is often complicated by fluidization and mechanical integrity issues. How often do you experience these types of fines handling issues, and what are some of your Best Practices to successfully mitigate these issues? What are your Best Practices for safe fines withdrawal from the ESP?

Electrostatic precipitators (ESPs) represent an effective medium for particulate emissions control and are, therefore, commonly used within the FCC industry, especially in North America. Although ESPs are not designed to capture all of the catalyst particles present in the regenerator flue gas, they usually exhibit sufficient performance to successfully reduce the particulate content in the flue gas below 50 mg/Nm3. As the question suggests, fluidization and mechanical integrity issues can significantly hinder the withdrawal and handling activities of catalyst fines.
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(2017) Question 71: What are your recommended configurations for main fractionator flash zone thermocouples to measure the flash zone temperature under the slurry bed?

It is important to measure the main fractionator flash zone temperature in the proper location such that it provides meaningful information. Temperature indicators (TIs) located below the slurry bed are at risk of coking, subject to maldistribution of vapor entering the tower, and are at a location before the vapors have been de-superheated.
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(2017) Question 72: Current economics drive unit operation to minimum slurry production limits, as defined by physical properties and rundown velocities/flow rates. What are your typical slurry limits, and what are your options to overcome those limits to further reduce slurry?

It is fair to say that past, current, and future economics will almost always call for the minimization of slurry production. As slurry production is minimized, the risk increases to foul exchangers or plug lines due to low velocities. Additionally, as slurry is minimized, the quality of the slurry will degrade, which will also increase the risk of fouling.
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(2017) Question 55: Given the expansion of the Industrial Internet of Things (IIoT), “Big Data”, cloud-based technologies, and advanced analytics, how are you applying these cutting-edge aspects into their work processes and toolkit to optimize FCC yield, reliability, and safety performance?

With the advent of “Big Data” and cloud-based technologies, refiners are now able to harvest mega data in a process environment. Hundreds of thousands of values are being generated every few seconds to measure, monitor, control, and optimize plant operations. The major benefit of “Big Data” is to demystify the different plant data used by various parts of the organization by using with a common set of information that is utilized by all departments. In the modern refinery, the key is transparency in strategy, philosophy, and shared goals.
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(2017) Question 56: 1973 FCC Process Question 13: When an older cat cracker is modified to incorporate riser cracking, has anyone encountered a limitation on the amount of conversion that could be obtained? In order to achieve maximum conversion, has anyone found it necessary to return to using a limited level of bed cracking?

Technip has a process in which a combination of riser cracking and bed cracking is used to maximize conversion. We have found that there are limits to the conversion that can be achieved in traditional riser cracking.
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