Agglomeration of particulate matter in chimneys using acoustic flow

Kristina Kilikevičienė; Rimantas Kačianauskas; Vytautas Rimša; Artūras Kilikevičius

doi:10.1016/j.heliyon.2024.e25306

Agglomeration of particulate matter in chimneys using acoustic flow

Heliyon. 2024 Feb 1;10(3):e25306. doi: 10.1016/j.heliyon.2024.e25306. eCollection 2024 Feb 15.

Authors

Kristina Kilikevičienė¹, Rimantas Kačianauskas¹, Vytautas Rimša², Artūras Kilikevičius¹

Affiliations

¹ Institute of Mechanical Science, Vilnius Gediminas Technical University, Vilnius, Lithuania.
² Department of Aviation Technologies, Vilnius Gediminas Technical University, Vilnius, Lithuania.

Abstract

The emission of micrometer-sized particulate matter on an industrial scale is causing increasing environmental concern about air pollution. Numerous industries and research communities need help to reduce micrometer-sized pollutants in the atmosphere. The current research investigates the acoustic agglomeration of particulate matter through a combination of experimental and numerical methods. Acoustic agglomeration is a process that involves using acoustic waves to influence the movement of particles in the air. Acoustic agglomeration operates by facilitating particle collision and simplifying the formation of agglomerates that are later removed through filtration. This article is focused on research on acoustic pre-processing with the aim of reducing atmospheric pollution caused by toxic combustion products. The capture of fine silica particles with diameters ranging from 0.3 to 10 μm, emitted through the chimneys of industrial enterprises, can be considered a significant technological innovation. The experimental part of the current research is conducted using a newly developed experimental bench. The assembly comprises the following key components: a wind tunnel, a particle dosing device, the agglomeration camera, and a particle concentration measurement device on the edge of the bench. A loudspeaker was used to evaluate the effect of sound pressure in the frequency range of 500-3000 Hz. A comprehensive CFD study of the particles was conducted, which included analysis of the boundary layer, facilitating a better understanding of the behavior of the particles and its potential to agglomerate. An experimental study of particle agglomeration, using an acoustic field with a frequency range of 500-3000 Hz, demonstrated the effectiveness of particle agglomeration of different diameters. The efficacy of particle agglomeration is up to 80 % when the sound pressure values were 129-135 dB; the highest efficiency was found at excitation frequencies of 1500 and 3000 Hz, respectively.

Keywords: Acoustic agglomeration; CFD; Relative entrainment factor; Silica microparticles.