Dynamics and control during startup of heat integrated distillation column

Abstract

To advocate the usage of process integration in industrial practice, it is important to be able to guarantee not only robust control during near steady state operation, but also to provide procedures for generating fast and reliable startup sequences. This contribution concentrates on describing a systematic procedure for development of plant startup sequences. The basis for the startup procedure development is available qualitative process knowledge. Application of the startup sequence generation procedure is demonstrated upon a heat integrated distillation plant. This plant illustrates some of the inherent effects of process integration upon a startup procedure. In particular, the effect of energy recycle upon the possible startup sequences and the effect of using an actuator for control purposes, i.e. the heat pump, which in itself requires significant startup time. The experimental application of two generated startup sequences illustrates that safe and reliable startups are ensured.