Wednesday August 28, 2019 from 13:30 to 15:10
Gas to liquid transfer enhancement during hydrate crystallization: Case study of CO2 hydrate for cold storage and transport
Véronique Osswald1, Amokrane Boufares1,2, Pascal Clain1,3, Elise Provost2, Didier Dalamzzone2, Hong Minh Hoang1, Laurence Fournaison1, Anthony Delahaye1.
1Irstea GPAN, ANTONY, France, Metropolitan; 2UCP, ENSTA Paristech, PALAISEAU, France, Metropolitan; 3Leonard de Vinci Pôle Universitaire, Research Center, PARIS - LA DEFENSE, France, Metropolitan
Secondary refrigerants, like ice slurries, are already used for industrial application, but their generation requires mechanical processes (scraping or brushing surface exchangers). CO2 hydrates slurries were classically obtained in a stirred reactor, by gaseous CO2 dissolution inside liquid water and cooling process.
In the present work, an original set up was developed in order to measure in real time and in situ the dissolved CO2 amount in the liquid phase during crystallization process thanks to the FTIR-ATR measurements.
Results on this device allowed to quantify crystallization driving force, related to supersaturation, and to focus on the crystallization limiting step. Some parameters were tested as stirrer type (propeller, Rushton turbine with hollow shaft) or stirring speeds. The increase of stirring speed or hollow shaft stirrer choice enhanced significatively gas/liquid transfer and thus strongly attenuated or even eliminated the limiting factor at the vapor-liquid interface.