A high performance CFD simulation tool, capable of quickly providing the most accurate calculations possible, is not enough. “You need to have a thorough understanding of the various phenomena involved: aeraulic, hydraulic and thermal factors, in order to be able to analyse and interpret the results in relation to the problem being studied”, stated Ilyes Mnassi from Cetim. With regard to the task entrusted to Cetim by TotalEnergies Fluids, involving the equipment of a hydrogenation reactor at its Bayport site (United States), while the calculations were rapid, it took several months to determine the model to be studied. “We had to find the most appropriate model for the desired performance based on the physical characteristics of the most commonly used fluid”, explained Hélène Leroy, Head of Processes and Projects at TotalEnergies.
Many interactions
There were many interactions between Cetim and the Head of TotalEnergies Special Fluids Department. These related to defining the scope of the study as well as bibliography and other work. During the course of the study, the stacking of balls proved to be a closer model than the initially favoured porous medium, which meant that new calculations had to be performed. “Cetim was pro-active and provided strong recommendations, stated Antoine Salomon, Head of Process Support Projects at TotalEnergies. Our interactions with the experts made it possible to find new avenues.” The study revealed that neither the number of twisted stacks nor their location on the second distribution tray affected homogenous flow. “We now know that the origin of the malfunction lies elsewhere, pointed out Antoine Salomon. Cetim saved us time and money by sparing us the need to shut down and drain the reactor to carry out repairs that were ultimately not necessary.” In addition, as a result of a previous study carried out by Cetim for the Oudalle site in France, TotalEnergies Fluids demonstrated to US operators the need for a pre-distribution tray to enable more homogenous flow. “The results (+ 14% improvement) convinced them that the investment was worthwhile, pending validation of a new technology”, commented Hélène Leroy.
