To overcome this situation, various process flowsheet simulators are used. This book describes the simulation, optimization, dynamics and closed-loop control of a wide variety of chemical processes using the most popular commercial flowsheet simulator Aspen . The book presents the Aspen simulation of a large variety of chemical units, including flash drum, continuous stirred tank reactor (CSTR), plug flow reactor (PFR), petroleum refining column, heat exchanger, absorption tower, reactive distillation, distillation train, and monomer production unit. It also discusses the dynamics and control of flow-driven as well as pressure-driven chemical processes using the Aspen Dynamics package.