Evaluation of a Pilot-Scale Electro-nanospray System for Decontaminating Pig Barns
Date
2023-07-24
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
0009-0000-8580-0004
Type
Thesis
Degree Level
Masters
Abstract
Exposure to bioaerosols, noxious gases, and high dust concentrations in confined livestock facilities have been linked to human and animal health hazards, with consequent adverse economic implications. In this study, an electro-nanospray system was developed for pig barn decontamination. This technology generates engineered water nanostructures (EWNS) through electrospraying and ionization of reverse osmosis (RO) water. The highly charged nano-scale water droplets encapsulate reactive oxygen species (ROS), which are responsible for bacterial inactivation and for capturing particulate matter through electrostatic forces.
Prior to testing the nanospray under actual swine barn environment, laboratory-scale experiments on bioaerosol deactivation were conducted using an acrylic chamber in which the electro-nanospray system was installed. Based on the deactivation efficacies of 16 needle spray injectors, the determined air flow rate obtained through theoretical calculation was 10 air changes per hour (ACH), which resulted in 49.3% bacterial reduction when Escherichia coli was dispersed as test bioaerosol pathogen inside the chamber. Furthermore, laboratory results using the developed nanospray with varying number of needle spray injectors indicated that 16 is the determined number of needle injectors for the volume of the test chamber used based on reduction efficiency. Surface decontamination with nanospray showed about 71%, 64%, 59%, and 51% reduction efficiency on plastic, metal, wood, and concrete surfaces, respectively.
In the in-barn experiments, one nano-spray treatment chamber was installed in the preliminary trial, while two units were installed in Trials 1 and 2. Results showed an average of 59% (preliminary trial) and 56% (Trials 1 and 2) reduction in bioaerosols in the airstream flowing through the nano-spray treatment chamber installed in the Treatment room. Preliminary trial showed that no measurable impact was observed on bioaerosol concentrations, while dust concentrations was reduced by an average of 28%. For Trials 1 and 2, results showed better effectiveness on culturable bacteria and dust concentrations with an average reduction of 31% and 42%, respectively. During the trial period, a higher increase in ammonia and carbon dioxide concentrations was observed in the Control room compared to the Treatment room, while surface decontamination showed about 46%, 36%, 31%, and 29% reduction efficiency on concrete, metal, wood and plastic surfaces, respectively. No significant difference in pig performance was observed between the two experimental rooms.
Description
Keywords
Bioaerosol deactivation, Surface decontamination, Electro-nanospray, Engineered water nanostructures, Pig barn
Citation
Degree
Master of Science (M.Sc.)
Department
Chemical and Biological Engineering
Program
Biological Engineering