To conquer the current FLNG challenge, experts have to answer the question " What effect does the movement of the ship have on the amine process?". It is necessary to rely on accurate knowledge of the impact of the floating support movement on the towers operation, to first secure then optimize the design of the process units. Indeed both flooding and internals efficiency will significantly impact the towers sizing (diameter and height) and thus the whole FLNG project.
It is a complex problem to be able to take into account the multitude of factors such as liquid viscosity, height of packing, diameter of column, acceleration, liquid/gas flowrate, type of packing, and motions imposed on the system. After first years of work when they completed an extensive review of bibliographic data to build an early model of maldistribution based on a theoretical approach, Total, Prosernat and IFPEN have now performed more than one year research and development at Heriot-Watt University to model mass transfer and hydraulics of a tilting, moving tower. To assess the impact of experimental column diameter and to be in position to scale-up the results, two columns have been used and will be described.
The program has included both static and motion tests with varying periods and angles, at different liquid loads to map the distortion of liquid distribution at adjustable heights of packing. The data now acquired has shown, depending on operating conditions, a significant impact on liquid distribution in the packing bed, leading to differentiated wetted zones, including dry and overloaded areas. Some examples will be given to illustrate the impact on tower efficiency and the corresponding tower oversizing based on the results of test campaign.