Aspen Technology, Inc.
Robust feedstock selection system for the chemical process industries under market and operational uncertainty

Abstract:

A computer system and method optimize feedstock selection planning for an industrial process by evaluating first and second stages at separate intervals throughout the planning process. Evaluating the first stage determines a set of robust feedstocks to procure on long-term contracts. The computer system and method solve, in parallel, multiple simulation cases of a non-linear model generated with different expectation values for uncertain input parameters related to selecting feedstocks to procure on long-term contracts. Probabilistic analyses on the solutions from the simulation cases, including the application of chance-constraints, determine the set of robust feedstocks to procure on long-term contracts. Evaluating the second stage determines a set of robust feedstocks to procure in the spot market, using the information from the first stage. Specifically, the computer system and method solve each of multiple new simulation cases of the non-linear model, generated with different expectation values for uncertain input parameters related to selecting feedstocks to procure in the spot market. Each simulation case is solved to determine breakeven prices for one or more available spot feedstocks, and probabilistic analyses are performed on the breakeven prices for these spot feedstocks to determine a set of robust feedstocks to procure in the spot market.