Comparing Temperature Difference Control Schemes for Dividing-Wall Distillation Columns

摘要

The operation of a DWDC, fractionating an ideal ternary mixture of hypothetical components A, B, and C, is studied to compare various temperature difference control schemes proposed so far, including temperature difference control (TDC) scheme, simplified temperature difference control (STDC) scheme, double temperature difference control (DTDC) scheme and simplified double temperature difference control (SDTDC) scheme. The nearly similar system performance of the STDC and SDTDC schemes to the TDC and DTDC schemes, respectively, indicates the great importance to control strictly the two sections along the dividing wall. With the two intermediate sections tightly controlled, the operation of the rectifying and stripping sections should then be tightened to improve further system performance. This gives rise to a novel SDTDC scheme involving two DTDC and two TDC loops, which enriches the potential alternatives to control the DWDC.