Q&A

(2015) Question 63: What type of facilities have you used to cool hot vacuum residue going to storage to avoid plugging problems and facilitate reprocessing?

I am going to focus on the system we have and also some of the issues we have experienced. The majority of our resid that is produced off the crude unit vacuum towers is sent through the hot resid system straight to the cokers. We have two crude unit trains.

(2015) Question 64: What are acceptable makeup water streams that can be used for coke cutting which will not affect the coke quality?

With regard to coke quality, a lot of the available streams are acceptable. A few of the additional considerations to take into account are: Is this makeup water stream going to add overall load to my wastewater treatment facility? Is this new water? Is this water that I can recycle? Streams that are acceptable are: stripped sour water. If you are not reusing this water at your desalters or FCC wet gas scrubbers, then it would be an acceptable stream.

(2015) Question 65: Discuss operating conditions and economic drivers to produce maximum diesel from the coker.

When your margins indicate the need to pull more diesel, you have two options: You can check the top of your tower, or you can adjust overhead temperatures and fractionations to confirm that you are pushing the maximum amount of heavy naphtha down into the diesel.

(2015) Question 66: Concerning new regulations for lower coke drum pressure prior to opening, what changes will you make?

Amec Foster Wheeler has several designs that could be incorporated in existing units to meet the expected EPA mandate of depressurizing the drums to 2 psig or less prior to opening the vent. Options include adding an ejector or vent gas compressor to lower the drum pressure.

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Q&A

(2015) Question 63: What type of facilities have you used to cool hot vacuum residue going to storage to avoid plugging problems and facilitate reprocessing?

(2015) Question 64: What are acceptable makeup water streams that can be used for coke cutting which will not affect the coke quality?

(2015) Question 65: Discuss operating conditions and economic drivers to produce maximum diesel from the coker.

(2015) Question 66: Concerning new regulations for lower coke drum pressure prior to opening, what changes will you make?