Distributed Economic Model Predictive Control of Hybrid SNCR-SCR Systems.

Selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) reactors are the most efficient systems for reducing NOx emission from power plants. This study proposes a distributed economic model predictive control (DEMPC) strategy for hybrid SNCR-SCR systems to reduce NOx emission and improve the economic performance of the process. First, a distributed model is used to represent the dynamics of the hybrid SNCR-SCR system. Next, criteria for assessing the economic and NOx removal performance are introduced. Then, a DEMPC strategy with contractive constraints is developed for denitration process control. Finally, the simulation results demonstrate that the NOx emission is limited within 50 mg/m3 and the economic performance of the denitration process is improved.