Electrical Agglomeration of Aerosol Particles in an Alternating Electric Field

Abstract

A laboratory scale test system has been designed and constructed to study the electrical agglomeration o f charged aerosol particles as a method to increase the fine particle collection eficiency o f electrostatic precipitators. The system consists of test aerosol generator, aerosol charger, agglomerator chambers, and aerosol measurement equipment. Air atomizing nozzles and the TSI six-jet atomizer have been used as the test particle generators. The test particles have been charged by a corona discharge. Two types o f agglomerator chambers have been investigated. In one agglomerator the gas flows between two parallel plates, across which the alternating high voltage is applied. The other agglom-erator is a quadrupole structure with cylindrical electrodes positioned between the grounded plates. Particle concentration and size distribution measurements have been carried out downstream o f the agglomerator with agglomerator voltage on and off. Particle concentrations and size distributions have been measured with differential mobility analyzer (DMA) and a Berner low pressure impactor. These measurements show that agglomeration causes about a 4%-8% decrease in the fine particle concentration when the total mass concentration is between 1 and 2 g/m\ There was no difference between the results measured with the parallel plate and the quadrupole agglomerator.

Systematic Approach to Optimization of Submicron Particle Agglomeration Using Ionic-Wind-Assisted Pre-Charger

“…Several ideas have been proposed to solve this problem by enhancing particle agglomeration to increase mean particle size, including acoustic coagulation to increase particle vibration and agglomeration (Noorpoor et al, 2013), electric agglomeration to increase particle electrostatic attraction and agglomeration (Kanazawa et al, 1993;Hautanen et al, 1995;Kildeso et al, 1995;Laitinen et al, 1996;Ji et al, 2004;Lin et al, 2011;Thonglek and Kiatsiriroat, 2014), and water vapor condensation to increase viscosity and agglomeration (Stairman, 1968), etc. Electric agglomeration is the process in which particles are charged in direct or alternate current electric fields, and collide and coagulate as driven by electric force.…”

Potential of electric discharge plasma methods in abatement of volatile organic compounds originating from the food industry

“…Abatement of aerosols with plasma treatment appears to be feasible due to complex charging phenomena taking place on the surface of the aerosol particle: the particles may agglomerate by sputtering (bombardment with ions), may be ionized (Mayya et al, 2004), and may be removed by gravity or centrifugal force (Urashima and Chang, 2000), electrostatic precipitators (Hautanen et al, 1995) or filtration. This abatement strategy concerns also vapour-phase VOCs, which may be removed from the gas stream by transferring VOC molecules to aerosol particles in a plasma discharge: the agglomerated aerosol particles are generated by ion-induced aerosol formation and the growth of cluster molecules and ions in the downstream afterglow discharge region (Urashima and Chang, 2000).…”

“…Research in aerosols, smokes and fogs removal deals cautiously with aerosols in dry air using oscillating AC dielectric barrier discharge (DBD) (Dramane et al, 2009), DC-corona (Borra et al, 1998;Hautanen et al, 1995) and electrostatic alternating separators (Hautanen et al, 1995) sensitive to the presence of air humidity: relative humidity is specified as not being permitted to exceed 5%. In such devices, sparking may easily be initiated and may have terminal consequences for the equipment.…”

Experimental Research on Discharged Characteristics of Dual Electrodes Charged System

“…Improving the efficiency of collecting submicron-sized particulate is a new way of dedusting technology [4], because the air that we live in is more and more bad. Theoretically, the methods of particle agglomeration are various: thermal [5], acoustic [5], magnetic [6], electric [7] etc. All the technologies could make submicron-sized particulate to agglomerating, but our country has no industrialized agglomerate device which can actual operate and get independent intellectual properly.…”