wide cut – main fractionators

widecutfrac

Details of four wide cut fractionation APC training sessions follow:

1. CDU operation and economics (100 minutes):

  • Overview
  • Boiling curves; TBP, EFV, ASTM
  • Product destination, specifications and unit economics.
  • Equipment configuration: sidestreams, pumparounds, condenser, compressor, total draw and part draw trays, etc.
  • Internal reflux profile.
  • Key control handles: Top temperature, sidestreams, pumparounds and stripping steam.
  • Major disturbances: feedstock switch, throughput changes, others.
  • APC requirements.

2. CDU inference methodology (100 minutes):

  • Empirical inference methods.
  • The GCC first principles model for predicting product properties
    • Product cutpoints, flashpoints.
    • Cold properties: Pour, cloud, CFPP and freeze.
  • Predicting internal reflux profile.
    • Internal reflux at key trays.
    • Overflash – the single most important operating variable.
  • Flooding detection methods.
  • Handling steady state inference models with dynamic inputs.
  • The role of on-stream analyzers.

3. Crude unit APC (100 minutes):

  • Crude switches and other major disturbances.
  • Typical constraints: Furnace capacity, column flooding, weeping or tray dry-outs, condenser capacity, desalter temperature, others.
  • APC structure: CV’s, DV’s and MV’s.
  • Product properties, internal reflux and overflash control during crude switches.
  • First level throughput maximization – constraint control.
  • Second level throughput maximization – yield trade-off, quality giveaway.
  • Simplified optimization.

4. Other main fractionators (50 minutes per fractionator):

Only two of the following fractionators would be covered:
  • Configuration, economics and inferential modeling of vacuum columns.
  • Configuration, economics and inferential modeling of high gas producing columns: FCC, coker or visbreaker fractionators.
  • Configuration economics and inferential modeling of hydrocracker fractionators.