Aromatics Units

The TTC unique PURE Extraction Process

Our process features and operating guidance can optimize your Aromatic unit to produce more capacity of saleable products of the highest purity. The Aromatic Extraction process is unique among refinery processes. Because of the non-idealities, designing and revamping units is considered the most complex and difficult of all refining processes.

With TTC technology, most customers experience the following benefits:

  • Most revamp and profit programs become cash neutral in 3 to 6 months
  • 20-30% increased capacity is typical for revamps
  • 10% decreased energy with no investment; 50% + with heat integration.
  • Fewer problems with corrosion
  • Inexpensive advanced control
  • Revamps exploit existing equipment with minimal new equipment
  • CH grade benzene and TDI grade toluene with any commercial solvents
  • Typical benzene recovery 99.9%, toluene 99.6% and xylenes 99%

Our TTEG Solvent Process

Use of less polar heavy glycols solvent can create the following benefits:

  • Much lower rate of corrosion and easier regeneration
  • Improved heat efficiency with low pressure steam
  • Solvent is easier to remove from product
  • Lower capital costs
  • Less expensive and more readily available solvent

BTX PURE Extraction Strategy
The unit priorities are satisfied in the order listed. Once a priority is optimized, we move to the next priority without losing the optimization of the previous priority.  (see Case Studies)

Aromatic Purity
The aromatic product purity specification is the most important benefit and needs to be robust.  Exceeded the spec causes a purity giveaway and falling below the spec leads to a product value downgrade to sale the product. The operational production specification should be reviewed for consistency with the market requirement demand. Product purity is the primary optimization parameter on the unit.

Unit Capacity
Additional unit capacity may be achieved with equipment upgrades such as TTC’s extractor trays, custom designed vapor-liquid trays, moving extractor feed location, improved recovery column feed distributor, improving top coalescing in the extractor and regenerator, and improved simplified process controls.

Aromatic Recovery
Recovery is optimizing by exploiting the size of the extractor and the operation of the recovery column.

Energy Utilization
Energy consumption is minimized by exploiting the existing equipment in the water circuit. A low reboiler temperature in glycol service exploits the balance between temperature and steam in the recovery column and the temperature of the extractor.  The control system is usually modified to minimize the “purity give-away.”