Electrostatic precipitation of PM2.5 is difficult because a stronger electric field is needed to manipulate the behaviors of finer particles, leading to higher energy consumption and ozone generation. Using particle image velocimetry (PIV), we explore whether inducing particle collective behaviors within electrostatic precipitators can improve the collection efficiency of finer PM in indoor spaces.

Nonthermal plasma (NTP) has been applied to inactivate viral aerosols containing Porcine Reproductive and Respiratory Syndrome virus (PRRSv) and H1N1. Its concept relies on generating reactive radicals (RRs), which have strong oxidative potentials and have been shown to inactivate airborne viruses once in contact. However, the process also produces a trace amount of ozone that becomes troublesome when using NTP indoors. At NIU, we are developing a compact, mobile ozone removal module using activated carbon for a wearable NTP technology developed at Taza Aya Inc. 

In collaboration with Taza Aya Inc., we aim to determine a chemical analyte to measure the concentration of reactive radicals in air during NTP discharge.

The Porcine Reproductive Respiratory Syndrome virus (PRRSv) is an economically significant disease affecting U.S. swine production. This project centered on developing a packed-bed non-thermal plasma (NTP) reactor targeting PRRSv. The studies showed that the packed-bed reactor led to a 2-log reduction in MS2 virus under a discharge voltage of 30 kV and a flow rate of 6 CFM. 

The electrical properties of aerosol particles play an essential role in the performance of electrostatic precipitators (ESPs). This project measures the electrical resistivity of powder admixtures composed of resistive fly ash and conductive powdered activated carbon (PAC). The results showed that ESPs can induce differential collection behaviors between the two particles. ADA-Carbon Solutions sponsored this project. 

Due to triboelectric charging, particle agglomeration in the sorbent injection system reduces the efficiency of gaseous pollutant removal. In this project, we developed an optical particle agglomeration sensor based on the theory of light extinction. The sensor comprises a HeNe laser coupled with a photodiode and a vibratory sorbent feeder. The powdered mercury sorbents are aerosolized by compressed air and conveyed through a rubber tube. As shown, the laser beam is then directed through the particle flow. The optical sensor infers the change in particle size distribution based on the change in light extinction ratio. BASF Catalysts sponsored this project.