Droplet nucleation in CCS/U relevant systems – development of hight-pressure expansion chamber

0573239 - ÚT 2024 NO eng O - Ostatní výsledky
Vinš, Václav - Hrubý, Jan - Čenský, Miroslav - Nikl, Zbyněk - Lukianov, Mykola - Blahut, Aleš
Droplet nucleation in CCS/U relevant systems – development of hight-pressure expansion chamber.

Grant CEP: GA MŠMT(CZ) EF16_019/0000753
Institucionální podpora: RVO:61388998
Klíčová slova: carbon dioxide * CCS/U * droplet nucleation * experiment * phase transition
Obor OECD: Thermodynamics
https://www.sintef.no/projectweb/tccs-12/

A unique in-house designed experimental setup for investigation of CO2 droplet nucleation in various CCS/U relevant fluid systems is being developed. Accurate knowledge of phase transitions, i.e. nucleation and growth of droplets, is crucial for an effective design of many CCS/U technologies. Transport and treatment of CO2-rich mixtures are dynamical processes whose simplification as mere thermodynamic equilibria can lead to substantial discrepancies between the design and real operational conditions. Our team performs research on droplet nucleation using two expansion chamber experiments. The measurement principle is based on a controlled rapid pressure drop of a carrying gas resulting in a sharp temperature drop of the fluid mixture within the chamber. A low-pressure chamber allows for investigation of water nucleation in gaseous CO2 relevant, e.g., for driers of CO2. The high-pressure chamber is intended for investigation of nucleation of CO2 in various carrying gases such as argon, nitrogen or methane. The nucleation can be measured both in a high-pressure supercritical fluid and a low-pressure vapor. The apparatus allows for measurements under wide operating conditions at temperatures from –20 °C to +150 °C and pressures up to 100 bar, i.e. both below and above the critical point of CO2. Besides the stainless-steel expansion chamber, which is currently under development, other crucial components of the apparatus are the mixture preparation device (MPD), the expansion setup and the light-scattering unit. MPD enables the preparation of a fluid mixture of a given composition by precise setting the flow rates of individual components through the expansion chamber. This approach allows continuous flushing of the entire system in order to avoid the influence of impurities acting as unwanted nucleation cores. The expansion setup is based on two valve systems, one for low pressure expansion from up to 7 bar and other for high pressure expansion from up to 100 bar. A challenge for a proper design of the expansion system is avoiding acoustic oscillations. The expansion system was successfully assembled and tested including the fast-response pressure transducers and data acquisition unit. Current activities focus on the final design and manufacture of the expansion chamber equipped with sapphire windows and the adjustment of the optical setup.
Trvalý link: https://hdl.handle.net/11104/0344120