Arnaud Nougues - Yokogawa Europe Solutions B.V.
An Advanced Process Control (APC) system has been successfully implemented by Yokogawa on a Delayed Coker Unit (DCU) with very high uptime exceeding 95%. This APC application is raising the performance level of unit operations and results in substantial economic benefits from product upgrading and throughput maximization.
A Delayed Coker unit is an established candidate for the application of APC, however the semi-batch nature of the process, in particular, the large disturbances caused by periodic drum switches poses unique challenges for APC. A conventional feedback control system is not adequate. The APC design should include among others an effective strategy for automatic detection of disturbances caused by drum switch events and robust handling of process disturbances. Yokogawa’s APC technology SMOC (Shell Multivariable Optimizing Control) and its successor PACE (Platform for Advanced Control and Estimation), known for their unique way of handling unmeasured disturbances with a “gray box” model representation, is particularly well suited for this DCU application.
This presentation describes the main features of the APC application on a Delayed Coker and illustrates the actual controller performance.