Q&A

(2019) Question 44: What is your recommended back up options for slide valve / plug valve Hydraulic Power Units? Are electric actuators an option? What are the response times?

What is your recommended back up options for slide valve / plug valve Hydraulic Power Units? Are electric actuators an option? What are the response times?

(2018) Question 44: Describe your procedures for placing and operating the FCC in hot standby/safe park mode. What safety concerns do you consider and what safeguards should be in place?

If the air blower is not running, things you should consider are ensuring all ignition sources are shutdown, bypassed or isolated (ESP, torch oil, DFAH, CO Boiler). Verify all hydrocarbon sources to the reactor, riser and regenerator are closed (fresh feed, any recycles, torch oil, fuel gas purges, LCO quench, etc.) and all sources of air are not being injected (main air, plant instrument air, fluffing air, etc.).

(2018) Question 45: What are the safe and reliable options for rodding out plugged bleeders such as hydraulic ram pumps, packing gland / drill assemblies or tangential bleeders? How are these options used in a best practice for ensuring piping is hydrocarbon free and ready for maintenance?

Rod out tools or bleeder cleaners are safe and effective at clearing clogged drain, vent and instrument valves to be cleaned during normal operations. Most include some type of drill bit and local pressure gauge and are designed to handle high temperature and pressure applications.

(2017) Question 3: What are your Best Practices for unloading solid phosphoric acid (SPA) catalyst from a catalytic polymerization unit, and what safety issues do they address?

There are two types of Honeywell UOP Cat Poly reactors: chamber and tubular. Each has different unloading concerns, and there are several different unloading options available for each.

(2017) Question 4: For the isomerization unit, what is your treatment for the streams containing high concentrations of hydrochloric acid (HCl) in the reactor emergency depressurization system?

Honeywell UOP does not include treatment of gas from the reactor effluent as it enters the flare header when using the emergency depressuring system in our Penex™ and Butamer™ process unit designs.

(2017) Question 5: Is the presence of pyrophoric compounds common in feed/effluent exchangers? What neutralization methods do you employ prior to exposing the equipment to the atmosphere?

In 2015, UOP led a Principles & Practices session on the topic of NHT (naphtha hydrotreater) and reforming unit feed/effluent exchanger fouling and cleaning.

(2019) Question 8: Where is salt (NH4Cl or (NH4)2S) fouling most likely to occur? What are common practices for monitoring and mitigating?

ABIGAIL SLATER (HollyFrontier)
Salting typically occurs in the reactor effluent exchangers (shell and tube and fin fans), recycle and net gas compressors, and product stabilizer overhead system (top trays, overhead condenser, etc.). Common monitoring practices on exchangers and fin fans can be

(2019) Question 9: How do you track chloride in liquid/gas/LPG? What are your criteria for replacing adsorbent in chloride treaters?

DAVINDER MITTAL (HPCL Mittal Energy)
Chlorides have been a long standing issue in catalytic reformer operation. Until a few years ago, the focus on preventing operational problems from the chloride compounds in the catalytic reformer product stream was to remove HCl. More recently, a growing

(2019) Question 10: What causes metal-catalyzed coking (MCC) that obstructs catalyst circulation in CCR reformers? What actions do you take to mitigate MCC formation?

BILL KOSTKA (AXENS NORTH AMERICA)
Metal-catalyzed coke (MCC) formation typically occurs on 3d valence transition metals such as iron and nickel. Under CCR-like conditions of low hydrogen partial pressure (less than about 620 kpa), high temperature (more than about 480 °C) and low or stagnant flow

(2019) Question 11: Where are your liquid-phase chloride treaters installed for reforming units? What are the advantages of each location?

BILL KOSTKA (AXENS NORTH AMERICA)
Liquid-phase Cl treaters are typically used in three locations for reforming units.

Treating the unstabilzed reformate stream provides several advantages. The stream is heated upstream of the stabilizer column which ensures that any ammonium chloride is

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