Aspen PIMS: Advanced Refinery Planning Models

Course Id:  RPA301   |   Duration:  5.00 day(s)   |   CEUs Awarded:  3.5   |   Level:  Advanced

Course Objective

This is an advanced course for experienced PIMS users. Learn to debug recursion structure and problems. Address Mixed Integer Situations using Aspen PIMS MIP capabilities. Apply Aspen Blend Model Library and other blending techniques to model rigorous blending. Troubleshoot modeling and convergence problems and learn PIMS?s non-linear functionalities to perform Solution Analysis. Manage local optima problems.

Course Overview

  • Debug properties recursion and error distribution structure and problems
  • Address Mixed Integer Situations using Aspen PIMS MIP capabilities
  • Apply Aspen Blend Model Library and other blending techniques to model rigorous blending
  • Troubleshoot and solve modeling and convergence problems using Aspen PIMS reports and tools
  • Model special situations that require non-standard structure
  • Use Aspen PIMS’s non-linear functionalities
  • Perform Solution Analysis using Aspen PIMS-Advanced Optimization tools
  • Manage local optima problems in the DR and AO environments


  • Learn to apply advanced modeling techniques
  • Understand how to model various situations in both DR and using PIMS Advanced Optimization techniques
  • Enhance business value of your PIMS software by understanding and utilizing appropriate features


The participant should have a good understanding of optimization and Aspen PIMS. Typically, participants have many years of optimization experience and are concerned with the more detailed aspects of the system. Many participants have taken RPA101 Aspen PIMS: Introduction to Refinery Planning and RPA201 Aspen PIMS: Solving Refinery Planning Problems and want to learn about additional techniques used to model difficult planning problems.


  • Lectures and class discussions allow the participants to share questions and ideas on how to implement model structure to solve difficult problems
  • The class problems are designed to illustrate advanced modeling and troubleshooting techniques


Must have attended RPA201 Aspen PIMS: Solving Refinery Planning Problems plus extensive experience using Aspen PIMS.

Class Schedule

Class Agenda

RPA301: Aspen PIMS: Advanced Refinery Planning Models

Distributive Recursion

  • Discuss and review distributive recursion topics
  • Workshops:
    • Designated Distribution Coefficient
    • Designated Distribution Coefficient – Recognizing Poor Modeling

Mixed Integer Programming
  • Discuss and review the following topics:
  • Mixed Integer Basics
  • Aspen PIMS MIP in Blending
  • Non-Convex Tiered Pricing
  • Workshops:
    • Blending: Component Limit Setup
    • Blending: Imposing Given Limits
    • Swing Cuts: Crossover
    • Pricing: Crude Oil Pricing Structure

Crude Distillation
  • Identify and explain the Aspen PIMS crude architecture
  • Discuss various modeling scenarios (cuts, swings, vacuum, recycle stream)
  • Workshop: Adding a Recycle Stream to Atmospheric Distillation

Advanced Topics in Blending
  • Identify and explain Aspen PIMS blending tables and structure
  • Workshops:
    • Fix a missing gravity message and note the effect in a model
    • Model a given limitation volumetrically
    • Modify a feed pool to limit a feed quality to a process submodel in a model
    • Quantify the difference between weight and volume blending

Aspen Blend Model Library
  • Identify and explain the Aspen Blend Model Library (ABML)
  • Demonstrate how to add the ABML to an Aspen PIMS Model
  • Workshop: Using Aspen Blend Model Library (ABML)

Model Troubleshooting
  • Identify and explain the following troubleshooting topics as the relate to Aspen PIMS:
  • Infeasible Models
  • Materials Out of Balance
  • Non-convergence
  • Local Optima
  • Review common problems with  model structure

Troubleshooting Tools in Aspen PIMS
  • Identify and explain tools for troubleshooting in Aspen PIMS
  • Workshops:
    • Resolving Infeasibilities
    • Run the Infeasibility and Solution Status Data Assistants
    • Activate the infeasibility breakers for specification blends in table SCALE
    • First-pass infeasibility problem related to a poor initial guess
    • Identify which properties are causing a given error message

Post Optimal Analysis
  • Discuss post optimal analysis tools and reporting in Aspen PIMS

Throughput Dependent Yields
  • Identify and explain modeling throughput dependent yields
  • Discuss submodel structure
  • Discuss throughput dependent yields with nonlinear formulas
  • Workshop: Implement a throughput dependent yield case using recursion structure (DR Solution) or nonlinear formulas (Aspen PIMS Advanced Optimization Solution)

Common Operating Conditions
  • Identify and explain the use of submodels to represent common operating conditions
  • Workshop: Divide a given reformer model into two submodels and implement the models so that both reformer units operate at the same severity.

Subtractive Recursion
  • Discuss and review subtractive recursion topics
  • Workshop: Use subtractive recursion to compute the resulting properties for a given gasoline stream.

Quality Cross Products
  • Introduce quality cross products and blending specifications
  • Discuss implementing quality cross products with nonlinear formulas
  • Workshop: Implement a submodel to specified quality constraints

Contaminant Removal without PCALC
  • Discuss common modeling techniques
  • Discuss using nonlinear formulas instead of PCALC
  • Workshop: Model a Hydrodesufurization Unit without PCALC

Quality Dependent Capacities
  • Discuss feed quality considerations and associated Aspen PIMS structure
  • Workshop: Quality Dependent Capacity

Aspen PIMS Simulator Interface
  • Identify and explain the Aspen PIMS Simulator Interface (SI)
  • Discuss simulator execution requirements
  • Workshop: Model an Aniline Improver

Multiple Paths
  • Discuss how Aspen PIMS recognizes and resolves multiple paths

Introduction to Aspen PIMS Advanced Optimization
  • Introduce Aspen PIMS Advanced Optimization capabilities

Aspen PIMS Advanced Optimization:  XNLP and XSLP
  • Explain Advanced Optimization and XSLP
  • Convert DR model to XNLP

Aspen PIMS Advanced Optimization:  Solution Analysis
  • Discuss solution analysis tools
  • Complete the workshop: Solution Analysis

Aspen PIMS Advanced Optimization:  Global Optimization
  • Discuss global optimization methods

Aspen PIMS Advanced Optimization:  Nonlinear Formula Facility
  • Discuss nonlinear formulas in Aspen PIMS Advanced Optimization

External Models in Aspen PIMS Advanced Optimization
  • Review old ways of adding nonlinear models:
  • Generalized nonlinear recursion (NONLIN/CURVE)
  • SI (Simulation Interface)
  • Introduce new ways of nonlinear modeling:
  • Nonlinear Equations
  • External Models

High Performance Computing
  • Use new XLP Matrix Generator functionality
  • Use Parallel Processor architecture for running multiple cases and Global Optimization Multistart

Aspen Technology, Inc. awards Continuing Education Units (CEUs) for training classes conducted by our organization. One CEU is granted for every 10 hours of class participation.