Control Structure Design for Parallel Processes

Parallel process units are often encountered in chemical process systems for different considerations, e.g., parallel reactors from reactor network synthesis, parallel columns for heat integration. One notable example is the feed split configuration of heatintegrated distillation columns. In this work, the control of parallel processes is illustrated with the heat-integrated distillation column example. Results show that more consistent control performance can be achieved using the proposed control structure for both feed composition and feed flow disturbances. More importantly, the improvement is obtained using simpler instrumentation and much less engineering effort.