Application of Plantwide Control to the HDA Process. IIRegulatory Control

Abstract

This paper describes the design of a control structure for a large-scale process, the HDA plant. Steady-state "top-down" analysis and optimization of the process 1 was used to select 16 sets of candidate "self-optimizing" primary (economic) variables. In this paper, we focus on the remaining "bottom-up" steps dealing with deciding where in the plant the production rate should be set; design of the regulatory control layer; design of the configuration of the supervisory control layer; and nonlinear dynamic simulations to validate the proposed control structure. Emphases is given to the systematic design of the regulatory control layer for it constitutes the backbone on which the optimal operation of higher layer relies on. In order to carry out the analysis, steady-state and dynamic models are necessary and Aspen Plus T M and Aspen Dynamics T M are used extensively. The final control structure is robust and yields good dynamic performance.

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