The alkylation process combines C3 - C5 olefins (primarily C4) from the FCC unit with isobutane to produce high quality gasoline. The process occurs in the presence of either HF or H2SO4; this provides additional challenges that need to be considered.

State of the art processing technology and equipment are essential for efficient and reliable operation.

Alkylation process

The alkylation unit takes a relatively light olefin stream from the FCC unit and then mixes it with a recycle isobutane stream and an acid catalyst to produce high quality alkylate gasoline. After the reaction and settling stage, the product stream is processed to recover light ends, a large isobutane recycle stream, butane, and the alkylate product. This is done through a series of substantial distillation columns.This process uses Sulzer equipment in the mixers, settlers, pumps, and distillation columns.

These sub-columns are named in a self-explanatory way:

• HF Stripper: HF acid removal/recovery
• Depropanizer: Propane removal/recovery
• Isostripper/Main Fractionator: Isobutane and butanes recovery along with an alkylate bottoms product
• Deisobutanizer: Separates the isobutane overhead and normal butane as a side draw

Alkylate is superior gasoline blending component with low RVP and high octane. This process uses Sulzer equipment in the mixers, settlers, pumps, and distillation columns.