Chemical Engineering Research & Design, Vol.136, 11-24, 2018
Optimal design of an intensified column with side-reactor configuration for the methoxy-methylheptane process
In an effort to diminish energy consumption and improve economic performance, a distillation column coupled with an adiabatic side-reactor column configuration is proposed. The production of 2-methoxy-2-methylheptane is examined to show the promising potential of process intensification using the proposed side-reactor column configuration. In order to design a side-reactor that restricts the temperature of catalyst activity to 423 K, the pressure of the column and the flow rate of the feed stream withdrawn for the side-reactor are examined. An economic steady-state flowsheet is developed that minimizes the total annual cost by optimizing the column pressure, side-stream flowrate, side-stream withdrawn location, and reactor effluent reentry location. For the 2-methoxy-2-methylheptane process, the proposed side-reactor column configuration appears overwhelmingly superior in terms of capital, energy, and total annual cost compared to that of a conventional energy-intensive scheme. In addition, compared to a reactive distillation process, the proposed configuration reduces total capital investment by decreasing column diameter with a smaller catalyst load. Furthermore, additional benefits such as less expensive hardware requirement, easy catalyst removal/regeneration could be achieved. Finally, a multi-effect heat integration sequence is suggested to improve the energy and economic performance of the proposed configuration. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
Keywords:Process intensification;Side-reactor distillation;2-Methoxy-2-methylheptane production;Energy savings;Total annual costs