(440h) Study the Impact of the Tube Configurations on the Local Heat Transfer Coefficient in Mimicked Fischer Tropsch Bubble Column Reactor

Study the impact of the tube configurations on the local heat transfer coefficient in mimicked Fischer Tropsch bubble column reactor
Abdulrazaq Nadhim Alzamily1, Abbas J. Sultan1, Amer Aziz Abdulrahman1, Hayder Al-Naseri2, Laith S. Sabri1, Jamal M. Ali1
1Department of Chemical Engineering, University of Technology, Baghdad, Iraq
2Chemical Engineering Department, Tikrit University, Tikrit, Iraq

Global energy consumption is expected to double by 2050 when compared to 2000 due to the world's population is growing, and many living standards will continue to improve. Therefore, there is a need for seeking clean alternative energy sources to help meet this demand for energy consumption. One of these clean sources is natural gas, which is available in large quantities and it is the cleanest-burning fossil fuel. However, some natural gas resources are in remote locations: transporting the gas long distances by pipeline can be expensive and impractical. To overcome the problem of natural gas transportation, the natural gas can be liquified or turn it into liquid fuels and chemicals. Fisher-Tropsch (FT) synthesis is the key route for converting natural gas to liquid fuels and chemicals where syngas (H2 and CO) reaction over a catalyst into liquid hydrocarbons occurs. FT synthesis is highly exothermic (𝛥𝐻𝑟=−210 𝐾𝐽/𝑚𝑜𝑙𝑒), and hence intense heat exchanging tubes are needed to control the temperature. The preferred reactor for this Fischer Tropsch exothermic reaction is the bubble/slurry bubble column reactor because it has several advantages over other reactors. However, its design and scale-up process remain a complex engineering task, which becomes more complicated when a bundle of cooling tubes is inserted into this reactor. This difficulty comes from the interactions between phases and the absence of mathematical models for predicting hydrodynamic and heat transfer parameters for these reactors when equipped with a bundle of heat exchanging tubes. Therefore, this study investigates and quantifies the influence of different tube configurations on the local heat transfer by using an advanced heat transfer technique in mimicked Fischer Tropsch bubble column under a wide range of operating conditions.
To achieve this study's aim, a plexiglass column with an inner diameter of 0.13 m and a height of 1.83 m was designed and manufactured. A bundle of thirty stainless steel tubes covering 25% of the column's cross-sectional area has been inserted into this column to represent the industrial heat exchanging tubes used in the Fischer Tropsch process. These thirty stainless steel tubes were arranged in two configurations (square and triangular pitch) inside the column to address and quantify these arrangements' impact on the local heat transfer coefficient. The results and findings of this study will be presented in detail on the conference day.
The obtained data and findings from this study and previous studies will further enhance the fundamental understanding of vertical tubes' influence and their configuration on the local heat transfer coefficient. Additionally, the obtained experimental data will expand the database for the bubble columns with vertical tubes and serve as benchmarking data for advancing the heat transfer coefficient prediction and modeling not only in bubble/slurry bubble columns but also for the equipment, which is utilized in power generation such as boilers, boiling, and pressurized water nuclear reactors. Moreover, it provides information needed to advance the design, scale-up, and operation of bubble/slurry bubble column reactor for the Fischer Tropsch process.