Q&A

(2018) Question 41: What effective practices do you deploy to improve the removal of inorganic contaminants in crude such as iron and calcium? What has been the industry success rate with these practices?

Cracked feedstocks can be introduced into the crude unit from several sources; the most common of which in North America are diluted bitumen from Canadian sources, diluted crude oils from South American sources, and slop streams from cracking units onsite that are recycled into the reprocessed slop oil blended into the crude unit feedstream.

(2018) Question 42: Some of the lighter waxy crudes have higher paraffin melting points making it difficult to treat and remove solids, salts in the desalter. What practices do you deploy to manage these higher melting point waxy crudes?

Some of the lighter waxy crudes have higher paraffin melting points making it difficult to treat and remove solids, salts in the desalter. What practices do you deploy to manage these higher melting point waxy crudes?

(2018) Question 43: What are your economic and operational reliability implications of increasing cycles of concentration in your cooling tower?

Operationally, especially as production units are debottlenecked over time, increasing tower cycles could facilitate the ability to utilize existing Utilities Infrastructure. This minimizes the need to undergo a disruptive engineering and installation processes should unit capacity enhancement projects be identified.

(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.

(2018) Question 46: What is your strategy to minimize main fractionator bottoms (DCO/ Slurry) versus LCO production apart from feed quality/catalyst selection?

The primary operational handles to minimize bottoms production is optimization of the cat to oil in the R&R. As the C/O is increased more of the heavy oils will be converted. As with all good things in the FCC this can be taken too far. Limits can be reached on the actual operating equipment in this process.

(2018) Question 47: Are there any operational parameters that can be manipulated to improve the operation of the slurry circuit and minimize fouling? Can you outline the slurry exchanger circuit recommended design practices to minimize fouling, plugging and erosion?

Temperature: From experience, the rate of coke build-up increases greatly when the bottoms temperature is > 700F (370°C). It is recommended to maintain the bottoms temperature below 680°F (360°C) to be on the safe side.

(2018) Question 48: What is the range of activity for FCC catalysts in the FCCUs? When is catalyst activity considered too low? When do you decide to reformulate versus changes in operating conditions in order to increase unit conversion?

BASF receives ECAT from about 200 FCC units worldwide. Of these, the ECAT activity ranges from 60-80, with approximately 75% of the units operating in the 70-76 activity range. The global average for 2017 was 72.5 and so far in 2018 the global average is 72.7.

(2018) Question 49: As the demand for higher octane gasoline components increases and lobbying for a 95 RON gasoline standard continues, how are you adjusting your operations to meet the market demand? What FCC specific changes do you make to produce higher octane gasoline components?

Refiners are optimizing their gasoline blend components to maximize high octane components. Alkylate and reformate yields are becoming increasingly important, as well as minimizing low octane component yields. The emergence of tight oil feeds has created an increase in low octane natural gasoline and LPG saturate production.

(2018) Question 50: Butylene demand and prices in relation to other refined products reached a record level in 2017. What caused it and what can we do in the FCC to produce more butylenes?

Higher demand for butylene is result of octane shortage in the gasoline market stemming from several main causes.

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