On 11 May 2026 Giorgio Besagni presented AURIGA at the 55th European Two-Phase Flow Group Meeting, in a talk on the current status of the project and where it goes next.
The European Two-Phase Flow Group Meeting is the annual gathering of the European two-phase flow community, and the talk was the project’s first full presentation of itself to that audience: what AURIGA is trying to establish, and how far the first year has taken it.
The argument set out in the talk is the one the project is built on. Bubble columns are an attractive reactor for large-scale CO₂ absorption — simple, without moving parts, efficient in gas–liquid mass transfer and straightforward to scale — but the multiscale phenomena that govern the flow inside them are not understood well enough to be predicted. Local phenomena are known to govern the macroscopic behaviour, yet no consistent framework describes that interaction, so design still rests on empirical correlations that do not travel beyond the conditions they were fitted to. AURIGA aims at an analytical formulation of the bubble column operating curve which links local and global flow properties rigorously enough to predict the flow regime a priori, and in parallel at a proof-of-concept CO₂ absorption system based on ionic-liquid bubble columns.
On the status: the analytical formulation of the operating curve has been started, by analysing the different ways of interpreting the transition from the poly-dispersed homogeneous regime to the transition regime without coalescence-induced structures. A property-based methodology for selecting ionic liquids has been developed — a sequential pre-screening of thermodynamic and transport properties — and has produced the two solvents the project now works with, 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF₄]) and 1-ethyl-3-methylimidazolium acetate ([Emim][OAc]). The experimental work began at the bubble scale, with single-bubble shape and terminal velocity in [Bmim][BF₄]–water and [Emim][OAc]–water mixtures, and with the mass-transfer measurements that give the liquid-side mass transfer coefficient.