A programming language for batch process control

Abstract

Control systems for the stabilization of batch chemical processes are similar to those used for the operation of continuous chemical processes. Unlike continuous processes, however, batch processes are not operated in steady state, but instead move operating conditions sequentially from one steady state to another. Even continuous processes are operated in such an unsteady state during startup or shutdown operations or, often during grade or production rate changes. Today's control systems technology has become well standardized for the steady state, feedback and feedforward continuous loop control using a block oriented structure. Most often, batch processes are operated with feedback controls on those items which remain constant, some sequencing device for timed switching operations but with manual control over the required state transitions. This paper describes the requirements for a high level programming language to direct the performance of a microcomputer based control system in the control of batch processes.