The feed to an HF Alkylation unit typically contains about 10 – 20 wppm of Sulfur. Nearly all of the sulfur in the HF Alky feed makes ASO, which mostly stays in the acid phase in the reactor. This ASO is removed from the acid in the Acid Regeneration (or rerun) column and so most of the sulfur typically is rejected from the unit in the ASO product stream.

In recent years the gasoline blend pool has shifted due to increased ethanol blending, higher volumes of high RVP material from processing lighter crudes, and other specifications changes. How are you taking advantage of these changes to optimize the gasoline processing units?

Normally clay downstream of extraction lasts a long time. Units utilizing glycol can damage the clay easily if there is any glycol carry over.

What are the advantages and challenges associated with alkylating amylenes?

The n-butane stream from an alkylation unit contains some organic fluorides. The fluoride must be removed in alumina treaters before being fed to an isomerization unit because the fluoride is a catalyst poison. When the fluoride is removed from the organic fluoride molecule, an olefin is formed.

One metallurgy issue that has been a hot topic in recent years is the specification for low Residual Elements (RE) in carbon steel for HF service. Based on recommendations made in NACE paper 03651, ASTM developed Supplemental Specifications for carbon steel that can be called out in purchase orders for steel that is to be used in HF Alky service

What is your experience with advanced control of sulfuric acid flow and strength?

How do you assign process engineers responsibilities: are they divided by technology; operating complex; projects, etc.?

With a significant portion of the current workforce eligible for retirement, what are you doing to preserve and pass-down the knowledge to the new employees entering the industry?

CCR Platforming Unit Customers report 3.2 years on average between turnarounds. And 10 % of the units exceed 5 years. Although, catalyst change-out frequently determined this time previously, the ability to change out “on the-fly” while maintaining operations has removed this constraint.