Extended-life nuclear air cleaning filters via dynamic exclusion prefilters
- Micro Composite Materials Corp., Durham, NC (United States)
The primary objective of this investigation was to ascertain if a dynamic, self-cleaning particulate exclusion precleaner, designed for relatively large dust removal (2 to 100+ {mu}m diameter particles) from helicopter turbine inlets, could be extended to submicron filtration. The improved device could be used as a prefilter for HEPA filtration systems, significantly increasing service life. In nuclear air cleaning, its use would reduce the amount of nuclear particulate matter that would otherwise be entrapped in the HEPA filter cartridge/panel, causing fouling and increased back pressure, as well as requiring subsequent disposal of the contaminated media at considerable expense. A unique (patent-pending) mechanical separation device has recently been developed to extract particulate matter from fluid process streams based on a proprietary concept called Boundary Layer Momentum Transfer (BLMT). The device creates multiple boundary layers that actively exclude particles from entering the perimeter of the device, while allowing air to traverse the boundaries relatively unimpeded. A modified two-dimensional (2-D) computerized flow simulation model was used to assist in the prototype design. Empirical results are presented from particle breakthrough and AP experiments obtained from a reduced-scale prototype filter. Particles larger than 0.23 {mu}m were actively excluded by the prototype, but at a higher pressure drop than anticipated. Experimental data collected indicates that the filter housing and the inlet flow configuration may contribute significantly to improvements in device particle separation capabilities. Furthermore, preliminary experiments have shown that other downstream pressure drop considerations (besides those just across the spinning filtration disks) must be included to accurately portray the AP across the device. Further detailed quantitative investigations on a larger scale (1,000 CFM) prototype are warranted. 3 refs., 5 figs., 2 tabs.
- Research Organization:
- Harvard Univ., Boston, MA (United States). Harvard Air Cleaning Lab.; USDOE Assistant Secretary for Environment, Safety, and Health, Washington, DC (United States). Office of Environmental Guidance; US Nuclear Regulatory Commission (NRC), Washington, DC (United States). Office of Nuclear Regulatory Research; International Society of Nuclear Air Treatment Technologies, Inc., Batavia, OH (United States)
- DOE Contract Number:
- FG02-95ER82026
- OSTI ID:
- 567237
- Report Number(s):
- NUREG/CP-0153; CONF-960715-; ON: TI97008959; CNN: Contract DAAJ02-93-C-0015; Contract DAAJ02-95-C-0009; TRN: 98:003314
- Resource Relation:
- Conference: 24. nuclear air cleaning and treatment conference, Portland, OR (United States), 15-18 Jul 1996; Other Information: PBD: Aug 1997; Related Information: Is Part Of Proceedings of the 24. DOE/NRC nuclear air cleaning and treatment conference; First, M.W. [ed.] [Harvard Univ., Boston, MA (United States). Harvard Air Cleaning Lab.]; PB: 1022 p.
- Country of Publication:
- United States
- Language:
- English
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