Flash distillation modeling and a multiloop control proposal

This work presents an approach to flash distillation modeling including the effect of choke valve. That effect is commonly reduced to a constant separation value in both phase proportion and volatile separation. Here the equilibrium is included, using a fuzzy sub-model in order to avoid iterations inside the model. In addition, a multiloop control system is proposed and tested by simulating the process under closed loop operation. The detailed process model obtained is totally documented following a phenomenological based semiphysical modeling methodology. Only vapor and liquid valves at flash drum are assumed as ideal elements. The choke valve in flash input is modeled from its real mechanical and thermodynamic behaviors.