Refinery Blender

This unit operation has been rewritten to overcome limitations in the previous implementation. The look and feel remains similar. The impact of this is:

• Limits on numbers of feeds, products and constraints have been removed
• Any stream property can now be included in a constraint, adding access to the full range of built-in stream properties, stream bulk variables and user-added script properties
• More robust convergence by replacing the proprietary non-linear convergence algorithms with the SQP techniques of IP-OPT or the SLP techniques of XPRESS-SLP. (The previous implementation of XPRESS in the Blender used it only as an LP solver with a KBC proprietary recursion algorithm).
• Main impact is better convergence with volume-based pricing schemes
• Tradeoff is performance

Petro-SIM V4 also incorporates other optimisation-related changes. See the Flowsheet Optimizer and Data Reconciliation Utility for details.