Investigation of droplet nucleation in CCS relevant systems – design and testing of the expansion chamber

Miroslav Čenský,Bohuslav Šmíd,Václav Vinš,Jan Hrubý,Jiří Hykl,P Dančová

doi:10.1051/epjconf/201818002015

Miroslav Čenský, Bohuslav Šmíd + Show 4 more

Open Access

https://doi.org/10.1051/epjconf/201818002015

Copy DOI

Abstract

A unique in-house designed experimental apparatus for investigation of nucleation of droplets in CCS relevant systems is being developed by the present team. The apparatus allows simulating various processes relevant to CCS technologies. Gaseous mixtures with CO2 are prepared in a Mixture Preparation Device (MPD) based on accurate adjustment of flow rates of individual components [EPJ Web of Conferences 143, 02140 (2017)]. The mixture then flows into an expansion chamber, where it undergoes a rapid adiabatic expansion. As a consequence of adiabatic cooling, the mixture becomes supersaturated and nucleation and simultaneous growth of droplets occurs. In this study, we describe the design and testing of the expansion part of the experimental setup. The rapid expansion was realized using two valve systems, one for low pressures (up to 0.7 MPa) and the other for high pressures (up to 10 MPa). A challenge for a proper design of the expansion system is avoiding acoustic oscillations. These can occur either in the mode of Helmholtz resonator, where the compressible gas in the chamber acts as a spring and the rapidly moving gas in the valve system as a mass, or in the “flute” mode, where acoustic waves are generated in a long outlet tubing.

Highlights

The team of the Laboratory of Phase Transition Kinetics at the Institute of Thermomechanics of the Czech Academy of Sciences (CAS) is developing a unique experimental apparatus for investing the formation of droplets in CO2-rich systems.To obtain new valuable data for nucleation of droplets in binary and multicomponent mixtures important in the design of new Carbon Capture and Storage (CCS) technologies [1,2] is the main motivation for this research
Gaseous mixtures with CO2 are prepared in a Mixture Preparation Device (MPD) based on an accurate adjustment of flow rates of individual components [1]
A challenge for a proper design of the expansion system is avoiding acoustic oscillations. These can occur either in the mode of Helmholtz resonator, where the compressible gas in the chamber acts as a spring and the rapidly moving gas in the valve system as a mass, or in the “flute” mode, where acoustic waves are generated in a long outlet tubing

Summary

Introduction

Expansion cloud chambers have been used for the research of droplet formation for more than a century [3] and many high-quality data sets for homogeneous nucleation rates have been obtained using the so-called nucleation pulse method implemented in expansion chambers [4, 5]. In this method, nucleation occurs in a short period of time (typically 1 ms) and the. We describe the design and testing of the expansion part of the experimental setup

Experimental Apparatus

Results and Discussion

Conclusions

IPCC Special Report