Development of a Novel Method for Airborne Dust Reduction and Bioaerosol Deactivation Using Engineered Water Nanostructures (EWNS)
| dc.contributor.advisor | Zhang, Lifeng | |
| dc.contributor.advisor | Kirychuk, Shelley | |
| dc.contributor.committeeMember | Guo, Huiqing | |
| dc.contributor.committeeMember | Niu, Catherine | |
| dc.contributor.committeeMember | Crowe, Trever | |
| dc.creator | Yang, Eric | |
| dc.creator.orcid | 0000-0002-5562-1088 | |
| dc.date.accessioned | 2021-05-26T15:47:32Z | |
| dc.date.available | 2021-05-26T15:47:32Z | |
| dc.date.created | 2021-05 | |
| dc.date.issued | 2021-05-26 | |
| dc.date.submitted | May 2021 | |
| dc.date.updated | 2021-05-26T15:47:33Z | |
| dc.description.abstract | Airborne pathogens and dust particulates are associated with the infectious and respiratory diseases that increase morbidity and mortality in livestock operations. An environment-friendly, non-toxic, and inexpensive technique was developed for airborne bacterial inactivation in livestock operations. This technique is based on electrospray (ES) which converts water into highly charged nano-scale water droplets or engineered water nanostructures (EWNS). The EWNS has some unique physicochemical characteristics that may be important for dust reduction and bacteria inactivation. The nano-scale water droplets have high mobility, charged density, long lifetime, and contain reactive oxygen species (ROS), all of which would be beneficial for airborne dust reduction and bacterial inactivation. To date, there are no studies on the effectiveness of EWNS nanoscale droplets on airborne dust reduction and bioaerosol inactivation in livestock buildings. Livestock buildings have high ventilation rates, large variation of climatic parameters, and high concentration of airborne dust and bioaerosols in comparison to residential buildings. Therefore, the objective of this study was to design and optimize a laboratory-scale electro-spraying system for generating engineered water nanostructures (EWNS) and to test the airborne dust reduction and bioaerosol inactivation of EWNS. For airborne dust reduction, both poultry and swine dust, with size less than 50 µm were used to test the dust reduction of EWNS. The swine dust concentrations for both control and treatment trials were 14.3 mg/m³ at 5 air changes per hour (ACH) and 12.5 mg/m³ at 15 air changes per hour (ACH), respectively. The poultry dust concentration was 13.5 mg/m³ at 15 air changes per hour (ACH). The experimental results revealed that the highest dust reduction percentage was 72.9% and 83.6%, at 15 air changes per hour (ACH) for swine and poultry dust, respectively. Moreover, the liquid consumption of the newly designed EWNS generator was a maximum of 1.92 ml/h, which is much less than most of the studies for the applications of wet electrostatic scrubbers (WES) for air quality control in livestock barns. For the bioaerosol inactivation experiment, Escherichia coli W3110 was used as a representative strain for the bioaerosol generation. The airborne E. coli concentrations for both control and treatment trials were (2.0 ± 0.6) ×10⁴ CFU/m³ and (3.1 ± 0.1) × 10³ ± CFU/m³ at ventilation rates of 7 and 15 air changes per hour (ACH), respectively. The experimental results revealed that sprayed liquid at pH 7 had the highest inactivation of 69% at 7 air changes per hour (ACH), and 37% at 15 air changes per hour (ACH), respectively. Moreover, the sprayed liquid consumption of the newly designed EWNS generator was only 480 µl/h and EWNS particle number concentration can up to 120,000 #/ cm³ in a 250-L experimental chamber. Overall, the results from both airborne livestock fine dust reduction and bioaerosol inactivation indicated that the EWNS have a set of unique physicochemical properties and this newly designed EWNS generator is effective at reducing airborne dust concentrations and inactivating E. coli. | |
| dc.format.mimetype | application/pdf | |
| dc.identifier.uri | https://hdl.handle.net/10388/13399 | |
| dc.subject | Nanotechnology | |
| dc.subject | Air Quality | |
| dc.title | Development of a Novel Method for Airborne Dust Reduction and Bioaerosol Deactivation Using Engineered Water Nanostructures (EWNS) | |
| dc.type | Thesis | |
| dc.type.material | text | |
| thesis.degree.department | Chemical and Biological Engineering | |
| thesis.degree.discipline | Chemical Engineering | |
| thesis.degree.grantor | University of Saskatchewan | |
| thesis.degree.level | Masters | |
| thesis.degree.name | Master of Science (M.Sc.) |