Characteristics of particles deposited on a single free-fall charged droplet

Abstract

Particles deposited on a free-fall charged droplet were experimentally studied. A droplet, charged under 40% Rayleigh limit, fell through the particle chamber to capture particles by electrostatic attractions. The velocity of the droplet was smaller than 2.1 m/s. The particle-laden droplet eventually spread on a glass slide, which was further analyzed using optical microscope. It was found that the equivalent number of particles captured by the charged droplet were larger than that of uncharged ones by one order of magnitude at least. Remarkably, particles on the charged droplet agglomerated into a large cluster, which indicates that the agglomerated cluster can be actively precipitated due to the gravity force if the droplet completely evaporates. The front side of the charged droplet was the predominant region to capture the particles. However, the actual area of capture was smaller than hemispheric surface.

An experimental study on the removal of submicron fly ash and black carbon in a gravitational wet scrubber with electrostatic enhancement

“…Extensive studies have been reported to elaborate the principle and performance of this technique. 17,19,[23][24][25] Balachandran et al investigated the removal of cigarette smoke, as the source of submicrometer dust, by charged droplets, indicating that the cleaning performance was four times better than that in uncharged cases. 26 Jaworek et al built a multi-nozzle electrospray system and found that the removal efficiency of smoke particles (<1 mm) is up to 80-90% with a very low water consumption.…”

The Efficacy of Plant-Based Ionizers in Removing Aerosol for COVID-19 Mitigation

“…Evidently, without any ionizer, it takes around 24 minutes for the aerosol concentration to reduce by 95%. In the absence of ionizer and ventilation, the removal of human-generated aerosol can be attributed to gravitational settling, which depends on aerosol composition and size [ 39 – 41 ]. Turning on a commercial ionizer (inset in Figure 3(a) ) reduces the aerosol removal time to 15 minutes.…”

The Efficacy of Plant-ionizers in Removing Aerosols for COVID-19 Mitigation

“…In the absence of ionizer and ventilation, the removal of human-generated aerosol can be attributed to two main factors namely evaporation and gravitational settling, both of which depend on aerosol composition and size. [39][40][41] Turning on a commercial ionizer (inset in Figure 3a) reduces the aerosol removal time to 15 minutes. When a small plant-based ionizer was turned on, it shows high efficacy in a 0.5 m 3 enclosure in reducing the time taken to clear the aerosol from 24 minutes to 6 minutes.…”