Bench-scale evaluation of an energy efficient acoustic aerosol purification device with a newly designed bioaerosol testing and evaluation chamber

Bioaerosol;Energy Efficient Air Purification;Test Chamber;Indoor Air;American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 52.2

Nelson, Andrew J. ; Rood ; Mark J.

关键词: Bioaerosol;    Energy Efficient Air Purification;    Test Chamber;    Indoor Air;    American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 52.2;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/24234/Nelson_Andrew.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

The most common method to purify building air of particulate matter is fabric filtration that can cause a large pressure drop, resulting in high-energy use for adequate protection.Facilities requiring advanced protection against particulate matter typically utilize high efficiency particulate air (HEPA) filters capable of removing 99.97% of particles larger than 0.3 μm in diameter.These filters have high associated energy costs due to pressure drop and can become contaminated with potentially hazardous material during normal operation. Hence, it is important to test alternative low pressure drop (LPD) methods that treat indoor air streams to achieve high particle removal efficiencies while also achieving high operational stability.A bench-scale test chamber has been designed, assembled, and validated for the evaluation of operational characteristics of novel LPD filtration technologies at flow rates up to 50 CFM (1.4 m3/min) including removal efficiency, pressure drop, and power consumption.The chamber is based on ASHRAE Standard 52.2 and is carefully designed to meet all validation metrics put forth in the standard.Aerosol particle removal technologies can now be tested at the bench-scale over a range of operating conditions to assess the effects of flow rate and power on collection efficacy.Additionally, these technologies can be evaluated for viability of retrofit installation and maintenance.Based on results from bench-scale investigations, the LPD filtration technologies will be evaluated further in a relevant environment simulated at a pilot-scale test-bed facility, in cooperation with the Department of Defense Joint Program for Collective Protection.In this research, a novel Acoustically Enhanced Impaction (AEI) air purification technology is evaluated as a potential alternative to HEPA filtration in building protection applications.AEI utilizes intense sound fields to induce aerosol drift and enhance probability of impaction on coarse filter media to collect the particulate matter within the device.The newly designed test chamber was implemented to characterize pressure drop, graded particle removal efficiency, and power requirements of the AEI.These results were compared to pressure drop and graded particle removal efficiency of conventional HEPA filters based on data available in the literature.A cost analysis was prepared to compare annualized operational cost of the current first-generation AEI device with commercially available HEPA filtration.Finally, projected annualized operational cost was calculated and compared for the AEI device, HEPA filtration, and an Electrospray Enhanced Impaction (EEI) method of air purification.The test chamber was also developed to evaluate an EEI system for energy efficient air purification.EEI utilizes electrospray ionization of particles followed by downstream collection on charged plates.This device will be tested in the near future once it can be interfaced with the test chamber.