Control of new energy‐intensified triple column extractive distillation using feed split technique

Abstract

BACKGROUND Here, we investigated the control performance of extractive distillation intensified with ‘feed split’ (FS) technique – a process intensification technique that has not been widely applied to extractive distillation. Today, only a handful of studies have been reported on this topic, with only one focusing on the control performance and reporting the significant trade‐off between the steady‐state and dynamic performances. Nonetheless, the previous control study was based on the complex double column FS configuration. Recently, a new triple column FS configuration was reported (Sep. Purif. Technol. 2022 (297) 121467), but its control performance was not investigated. Hypothetically, the triple column FS configuration is less complex and does not involve any column integration and thus, may demonstrate a better dynamic performance. This study analyzed the control performances of the triple column FS configuration and the conventional configuration for the binary azeotropic separation of tetrahydrofuran and ethanol. RESULTS Two types of control structures were examined for both configurations, i.e., the basic temperature control structure and the different feed forward temperature control schemes. The best control structure from each configuration is compared and findings showed that the conventional configuration provides better controllability performance. CONCLUSION Our results suggested that the conventional configuration can bring the product qualities closer to their setpoint, while providing a lower transient deviation. © 2023 Society of Chemical Industry (SCI).