Performance Assessment of a Batch Distillation System

Abstract

In this study, the performance analysis of a batch distillation system, which is being used to recover ethylene glycol from the waste products of a chemical plant, was conducted using the exergy analysis method. The analysis was relatively thorough and detailed, including a broad modelling of the system and a comprehensive “reference temperature” investigation. The aforementioned waste solution contains water, glycols, and some anhydrides. The purification process of this waste is sustained using a distillation system that operates in a batched manner and is heated using an electric heating system. In this study, the heating system, reboiler, and condenser groups of the distiller were investigated to better understand the characteristics of the system and to reveal the efficiencies “exergetically”. Overall, with data from the real-case and data gathered from the experiments, the system’s exergetic efficiencies are calculated, over time, during the distillation process. This way, the major exergy destruction points for the system are pointed out, in hopes of reaching better efficiency and reduced costs for the system. The effect of the environmental temperature is also investigated with the utilized exergetic model. As a result of the investigation, the overall efficiency for the distillation system was found to be 3.41% and the overall exergy destruction as 282.13kW.

Keywords

• Exergy; batch distillation; separation; ethylene glycol; performance investigation

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