Q&A

(2014) Question 48: Can DAO (Deasphalted Oil) be processed in a full conversion hydrocracker and if so what concerns would need to be considered?

Typical DAO stream composition metals (5 -100 wppm), Conradson Carbon (2 – 10 %wt), Asphaltenes (heptane insoluble of 500 -1000 wppm or more) and distillation endpoint (1300-1500 F or more) are detrimental to achieving economic catalyst life and conversion at hydrocrackers.

(2014) Question 49: What experience have you had in identifying the incompatibility of feeds to a Hydroprocessing Unit? Can these feeds create pressure drop issues? What kind of feeds/compounds are typically incompatible? What test(s) do you suggest? Are there any solutions such as catalyst loading modifications to eliminate typical issues?

Feed stock incompatibility has typically been observed in VGO hydroprocessing and is related to the precipitation of asphaltenes.

(2014) Question 50: What strategies have you used for maintaining the ratio of cracked/SR (Straight Run) feed for hydrotreating units as the coker cycles through coke drums?

What strategies have you used for maintaining the ratio of cracked/SR (Straight Run) feed for hydrotreating units as the coker cycles through coke drums?

(2014) Question 51: What is your minimum Cloud Point Improvement that makes economic sense to apply catalytic dewaxing vs. traditional (i.e. additives and kero blending) Cold Flow Improvement methods?

At low temperatures, products with “waxy” components start to crystallize and affect the flow characteristics of the product. To avoid problems of fuel supply to an engine or lubricating problems under low temperature conditions, diesel fuels and lube oils often have stringent specifications on flow properties at low temperature.

(2014) Question 52: Explain the differences with renewable and Biodiese. Can renewable feedstocks be co processed with traditional diesels in an existing ULSD (Ultra Low Sulfur Diesel) unit and how does this impact RIN's (Renewable Identification Number)?

Renewable Diesel is a hydrocarbon. Commercially, Renewable diesel is made from hydrotreating vegetable oil & animal fat. Renewable diesel must meet the specifications for diesel, either ASTM D 975 or D 396 in the United States.

(2014) Question 53 How are you planning to meet Tier III gasoline specifications? Please share your strategies for post-treat and pre-treat options, feedstock selection and catalyst technology? Can renewable feedstocks be co-processed with traditional diesels in an existing ULSD (Ultra Low Sulfur Diesel) unit and how does this impact RIN's (Renewable Identification Number)?

FCC gasoline has the highest sulfur content and is also the largest volume component of the mogas pool of a typical US refinery.

(2014) Question 54: What methods and technologies are you using to monitor vapor pressure and H2S levels in the vapor space in crude railcars and trucks? What engineering controls are being used by the rail and trucking companies to ensure that the vapor pressure and H2S are being met?

What methods and technologies are you using to monitor vapor pressure and H2S levels in the vapor space in crude railcars and trucks? What engineering controls are being used by the rail and trucking companies to ensure that the vapor pressure and H2S are being met?

(2014) Question 55: What operating procedures and designs are you using to increase the safety of drilling coke drums?

What operating procedures and designs are you using to increase the safety of drilling coke drums?

(2017) Question 28: Under what conditions will you strip sulfur from hydrotreating/hydrocracking catalysts?

Base-metal hydrotreating and hydrocracking catalysts are susceptible to sulfur stripping at high temperature in the presence of flowing hydrogen and in the absence of H2S. For that reason, we advise unit operators to avoid prolonged exposure of sulfided catalysts to flowing hydrogen at temperatures exceeding 500°F if the H2S content of the hydrogen is below 50 ppmv (parts per million by volume).

(2017) Question 29: What is the impact of processing unconverted oil (UCO) from a high conversion hydrocracker on the following downstream units: FCC, coker, base-oil unit, and lubes hydrocracker?

What is the impact of processing unconverted oil (UCO) from a high conversion hydrocracker on the following downstream units: FCC, coker, base-oil unit, and lubes hydrocracker?

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