Abstract Number: 1674 Working Group: Control and Mitigation
Abstract Over the past several years, indoor air quality has become a matter of increasing concern both due to the presence of non-viable pollutants (particles, volatile organic compounds, and gaseous pollutants) and viable pollutants (bacteria, viruses and mold). The efficiency of current media-based filters is limited to particulate removal and is proportional to the pressure drop across the filter. Electrostatic precipitators (ESPs) are considered a viable alternative to media based filtration technology since they contribute a much lower pressure drop and do not require frequent filter replacement. However, ESPs have a limited removal efficiency especially for ultrafine particulates and are associated with the production of harmful byproducts such as ozone.
In this work, we present the development of a scalable photoionization enhanced electrostatic purification (PE-ESP) technology for high efficiency removal of particulates [1]. A model driven approach was used to design and develop a parallel plate PE-ESP system. Air jet atomization of a KCl solution was used to generate aerosolized particles and the filtration efficiency of the SXC-ESP unit was measured using an optical particle counter (OPC) and a condensation particle counter (CPC).The PE-ESP system shows a 97-99% particulate removal efficiency in the 0.2 to 1 μm size range without the production of any measurable ozone. The efficiency without the photoionization was 50-60% in the same size range. The efficiency predictions from the model match well with the experimental measurements for both a conventional ESP as well as the PE-ESP. Owing to its high efficiency and negligible ozone production, the PE-ESP system has the potential of being used as a replacement for media based filters.
[1] Chadha, T.S., Biswas, P., Fang, J., Systems and methods for gas cleaning using electrostatic precipitation and photoionization, WO Patent App. 2017143255A1, 2017.