Q&A

(2017) Question 32: A) What are the variations of target efficiency that can be achieved in hydrogen plant operation? B) What are the operational factors that impact efficiency?

When discussing efficiencies, it is important to define the plant efficiency term. In most cases, hydrogen plant efficiency is measured by calculating the energy [BTU/scf (British thermal unit/standard cubic foot)] required to generate product hydrogen.

(2019) Question 52: What strategies have you employed to profitably manage Tier III regulations (i.e. crude purchasing strategy, pre/post treating, FCC operational changes, sulfur reducing additives, etc.)?

Question 52: What strategies have you employed to profitably manage Tier III regulations (i.e., crude purchasing strategy, pre/post treating, FCC operational changes, sulfur reducing additives, etc.)?

(2018) Question 5: What is your experience with CCR catalyst on-the-fly replacement compared to changing at turnaround?

On-the-fly catalyst replacements are becoming more common, but still an economic decision for the refiner based on trade-offs between the continuous replacement approach and the historical changing at turnaround approach. On-the-fly catalyst replacement allows for full catalyst replacement while catalyst circulation is maintained, with both reaction and regeneration sections still in operation to allow for reduced unit downtime.

(2018) Question 7: How do you monitor and protect the heater tubes from overheating in high temperature services such as catalytic reformer heaters? How is the tube wall temperature monitored?

As a first step and low investment solution, refiners will perform a visual check on the color of tubes to check for color differences or perform a thermal scan of the tubes. These solutions are not very accurate due to iron scale formation and ceramic coating on the tubes.

(2018) Question 8: Fixed bed reforming and CCR reforming recycle gas compressor washing to remove salt deposits. What is the frequency? What is the typical deposit composition? What is used to wash the compressor?

The recycle compressor is water washed at every catalyst regeneration (typically once per year) after the chlorination step. In addition, if there is any extended outage for mechanical work, the compressor will be water washed anytime there is an opportunity to do so as precaution.

(2018) Question 10: What are the problems with low coke operation in CCR reforming and how is it managed?

10% ethanol in gasoline regulation which lowered the gasoline octane required from the refinery. At 10% blending ethanol raises the (R+M)/2 octane of regular gasoline about 2 numbers.

(2018) Question 11: What constitutes adequate quench reserve when you process cracked feedstocks in hydrotreating units? In hydrocracking units? What if a mixture of both gas and liquid quench is used?

Maintaining control means that the dog walker – needs to be able to hang on to the dog – even if it starts to walk or run away. This takes adequate reserve strength - and an early detection and response when the dog just begins to become distracted or when we begin to feel the pull on the leash.

(2018) Question 12: Discuss impacts of hydrotreating operations required to meet Tier III regulations. Highlight the benefits and concerns of pretreat versus post treat operations including; impacts on cycle length, FCC yields, octane from post treating options, and gasoline blending.

Regulatory specifications for the gasoline and diesel pool, which are constantly evolving, have been in the forefront of refiners’ challenges in the last 15 plus years. In particular, the gasoline sulfur regulations have been a main driver for the remodeling of many refineries’ configurations.

(2018) Question 13: What factors do you consider when co-processing jet fuel in a distillate hydrotreater versus processing the jet separately (including feedstock and unit consideration)?

There are several considerations when deciding if jet fuel and diesel should be co-processed or hydrotreated separately. The most important consideration is if the jet fuel will be blended into the diesel product or if separate products are desired. The decision may depend on if you are looking at constructing new facilities or making the best use of existing equipment.

(2018) Question 14: In your experience, what operational factors contribute most to utility costs in hydrotreating units?

The biggest contributor to utility cost per barrel in a hydrotreater is probably the unit operating pressure. Higher pressure units require more energy to pump up the charge, hydrogen, amine and wash water.

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