With the introduction of more and more ethanol blends, the need for higher octane blendstocks has declined. The days of running max severity on refinery Reformer units are behind us. 

There are a few things to consider as you optimize operations around a new set of conditions.

H2 Yields

Lower Reformer severity on a means less hydrogen production. Depending on your refinery configuration that might just mean purchasing more hydrogen, but for many refiners the loss of hydrogen could mean a loss of hydroprocessing capacity.

purchasing some higher octane blend components may actually be more economic than increasing severity on your Reformer Unit.

Catalyst Selection

The catalyst used in your Reformer unit was likely selected based on the typical severity the unit was run at. If the operating range has changed, it’s very probable that a different catalyst may be more optimal.

Evaluate new catalysts based on the reformer severity that you currently run and also the parameters that are most important in the new environment. If hydrogen production is more important than octane at your refinery, make sure the catalyst vendor is aware of this and is formulating the catalyst to your updated needs.

Reformer Feed Quality

Another variable to be aware of is the quality of feed to the Reformer unit. As octane becomes less valuable, factors such as reformate volume yield and benzene content become more of a driver. 

Feed tailoring remains a valuable tool to optimize refinery operations. While cyclohexane is a good reformer feed molecule, methyl-cyclopentane, on the other hand, is rather poor.

Both molecules boil in the same range, but many refiners do not have adequate feedstock molecular analysis to distinguish between the various types of hexane molecules. Understanding refinery constraints (i.e. H2 or Benzene) will dictate the correct operating strategy.

Identifying an alternate homes for cracked naphthas can also improve reformer yields, thus requiring lower reformer severity. Since the market favors distillate production over gasoline these days, refiners can become creative in how they manage cracked naphtha processing.  Simple changes such as increasing cracked naphtha routing to jet to displace straight run naphtha can improve reformer feed quality significantly.

Gasoline Pool Octane

Let’s admit it, gasoline blenders are a unique breed of people. In my years in the refining business, I have yet to meet a gasoline blender that’s readily willing to try new things. I don’t blame them, as they have a lot of stress and change that they are constantly managing.

That being said, this is now the most opportune time to challenge habits of your gasoline blender. I can guarantee you that your gasoline pool is not optimized, and the reduced octane requirement these days offers an opportunity to review the refinery blend strategy. 

It is possible to not have any octane giveaway in the gasoline pool, but still operate reformer severity higher than necessary. If your refinery currently blends straight run naphtha to the gasoline pool, ask yourself if this is necessary.

Is the reformer operating at minimum severity? Do you have octane giveaway without straight run naphtha blending?

Finding the proper balance between reformer severity, hydrogen yield, and reformate quality is often a complex optimization process that requires a good refinery LP and refinery economist.  Make sure you’re aware of the impacts of all these variables, and that you’re using that as a lever for optimization when possible.