Spray scrubbing of particulate–laden SO₂ using a critical flow atomizer

Abstract

The performance of a spray tower using an energy efficient two-phase critical flow atomizer on the scrubbing of particulate-laden SO₂ using water and dilute NaOH is reported in this article. Experimentation revealed that SO₂ removal was enhanced due to presence of particles (fly-ash) and almost 100% removal efficiency was achieved in water scrubbing. The removal efficiency is elucidated in reference to atomizing air pressure, droplet diameter and droplet velocity besides other pertinent variables of the system studied. The presence of fly-ash particles improved the removal efficiency to about 20% within the range of variables studied. Empirical and semi-empirical correlations were developed for predicting the removal efficiency in water and dilute NaOH respectively. Predicted data fitted excellently well with experimental values. The performance of the spray tower is compared with the performances of existing systems and very encouraging results are obtained.

Keywords:

• Spray tower
• two-phase critical flow atomizer
• particulate-laden SO₂ scrubbing
• mass transfer enhancement factor
• mass transfer enhancement by fly-ash

Acknowledgment

Prof. M. N. Biswas thankfully acknowledges the AICTE Emeritus Fellowship awarded to him (2005–2007).