Document Type : Regular Article

Authors

• Dalia S Makki ¹
• Hasan Sh. Majdi ²
• Amer Abdulrahmn ³
• Abbas J. Sultan ⁴
• Bashar J. Kadhim ⁴
• Muthanna H. AL-Dahan ⁵

¹ The University of Technology/Department of Chemical Engineering

² Department of Chemical Engineering and Petroleum Indus-tries, Al-Mustaqbal University- Babylon

³ Department of Chemical Engineering, University of Technology Department.

⁴ Department of Chemical Engineering, University of Technology

⁵ Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, MO, USA

Abstract

This study involves designing and constructing a simulated Fitcher-Tropich bubble column reactor (FTBCR) that features a real heat exchanger, to investigate the influence of a real heat exchanger into a bubble and slurry bubble column (BC and SBC). The investigations were conducted in a (0.15 m) inner diameter Plexiglas (BCR) with varying gas flow rates ranging from (0.14m/s to 0.35m/s).
To replicate the industrial (FTBCR), a real heat exchanger was vertically installed, occupying 25% of the column cross-section, and comprised 18 copper tubes, each with a diameter of (0.016 m). Glass beads represented the solid phase with an average size of (150 μm), which were loaded volume of 40%. Furthermore, this investigation employed an advanced heat transfer technique to quantify the impact of the tubes and solid particles on the local instantaneous heat transfer coefficient (LIHTC). The investigations were conducted at three axial locations (H/D = 2, 3, and 4) and six radial sites along the column's diameter (±0.18, ±0.46, and ± 0.74). The results indicated that the (LIHTC) decreased as the gas flow rates increased at all radial and axial positions. Moreover, the (LIHTC) in the central zone increased by 82% compared to near the wall in two and three phases.
The model's validation was assessed by comparing the predicted and experimental values of (LIHTC) using Minitab software and response surface methodology (RSM). The results were consistent with the experimental results.
The regression model achieved for (LIHTC) in two and three phases (BCR) was (R2) (95.90) and (97.49), respectively.

Keywords

• Fischer Tropsch
• bubble/slurry column
• heat-exchanging tubes
• local instantaneous heat transfer coefficient
• surface methodology