EVALUATION OF THE NUMBER OF TRANSFER UNITS(NTU) AND THE COLUMN HEIGHT BY USING ON-LINE TEMPERATURE MEASUREMENTS FOR A PILOT SCALE PACKED BATCH DISTILLATION COLUMN

Year 2012, Volume: 2 Issue: 1, 1 - 7, 23.07.2016

Adnan Aldemir Suna Ertunç Hale Hapoğlu Mustafa Alpbaz

Abstract

There have been relatively few experimental attempts at evaluating the column height and comparing experimental results obtained from a pilot scale packed batch distillation column with theoretical ones. In the present study, the pilot plant packed batch distillation column was used to distillate the binary methanol-water mixture, and to obtain on-line temperature values. The top temperature changes with time were observed at steady-state and dynamic conditions. The column was operated initially for approximately one hour at the total reflux. In this case, There were no feed and product flows. Temperature samples were taken on-line from the top and bottom of the column. Temperature profiles observed on the computer were recorded. Refractive index of the samples were determined. When the temperatures were constant, the system was at a steady-state condition for total reflux. After the system reached the steady-state condition the reflux ratio was adjusted to a certain level. From experimental top and bottom temperature values, two models were obtained between mol fraction and temperature. The mass transfer coefficient was calculated, and the final mol fraction of reboiler was determined. The column height was calculated and compared with the real packed height. It is noted that the equation used for mass transfer coefficient is considerable well

Keywords

Batch distillation, packed column, packed height, mass transfer coefficient

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