MPC utilizes the AFPM Safety Portal to communicate and share experiences and knowledge within our FCC Advisory Group. It is a vital component of our goal to improve process safety performance. We also have a Process Safety Advisory Program to learn from external industry and internal MPC process safety events, significant near misses, and high value learning events.

Phillips 66 has six ESPs (electrostatic precipitators) in service. We have not been immune to serious incidents on our ESPs. In 1994, we had an ESP explosion, which led to a fatality. So, in order to minimize the likelihood of these kinds of incidents happening again, the company has a standard that all of the refineries are required to follow.

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.

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.

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. 

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.

Calcium chloride is likely the bigger culprit in vacuum towers. If there is a 100°F difference in crude and vacuum transfer temperatures, some hydrolysis in the vacuum tower will occur. If the desired vacuum tower cutpoint can be achieved in a different way other than maximizing vacuum heater temperature, such as lowering column pressure, hydrolysis and subsequent salt formation will be reduced.

Preflash drums are useful for removing the vapor from the feed to the atmospheric tower, but there is a lot of debate about its purpose. Many people believe that this is done for energy purposes, but I think those who really study this come to the realization that it is not for energy.

I know this topic generated a lot of discussion in our Hydrotreating session yesterday. I am mainly, obviously, going to focus on the crude side of it. I will start by saying that basically, it starts with a process to analyze processed crudes for impurities to manage and minimize fouling coming from salts, asphaltene precipitation, and other impurities.

For the black and yellow wax, really the biggest issues we have seen are actually from what looks like upstream additives – bromides, in particular – that are coming out in the hydroprocessing area as bromic chloride salts. So that is a little different. Typically, we worry about ammonium chloride. Those two crudes tend to have bromine-type contamination, so you do see some issues with them.