This paper explores the effects of electrification of water sprays on the absorption of sulphur dioxide from exhaust gases. Electrification is associated with an appreciable improvement of sulphur dioxide absorption rate with low supplementary costs and candidates to be a valuable innovation for spray tower absorbers. Similar phenomena occur during thunderstorms, when scavenging of gases and aerosol are enhanced by the electric charge of raindrops.
This paper aims to describe the effects of electrification on SO2 absorption on the bases of experimental and theoretical analyses. The experiments involve absorption tests in lab-and pilot scale facilities, while theoretical modelling to assess the chemical and physical properties of charged droplets, their hydrodynamics and their mass transfer rates are presented. Water electrification is accompanied by a number of chemical-physics and morphological modifications of the sprayed droplets that modify the conventional absorption rate of soluble gases. The experimental and theoretical evidences indicate the need to analyse the electrified absorption within a new and integrated theoretical framework that we define chemi-electro-hydrodynamics (CEHD).