A Multivariable Approach for Control System Optimization of IGCC with CCS in DECAR Bit Project

IGCCs with CCS differ from existing IGCCs mainly because of steam integration between gasification process and combined cycle, and because of selective capture of CO2. A dynamic simulator of IGCCs with CCS considered in DECARBit project was developed by using a in house code, ALTERLEGO, and a commercial code ASPEN HYSYS®. Simulators were used to assess flexibility of the process design and effectiveness of the control system during load changes. Starting from steady state results at nominal load, the simulator development has been implemented to assure a stable transient behavior during load reduction. As a result of this study, the flue-gas temperature and IP pressure should be regulated at fixed setpoint. Moreover, critical behavior of CO shift temperature controllers,can be mitigated by means of suitable setpoint coordination.