Abstract
A two-stage filtration test system was successfully developed previously, and the objective of this study is to investigate the effect of pre-filter selection and face velocity of pre-stage and main-stage on the loading characteristics of a two-stage filtration system. Three different types of pre-stage filter media with different capture efficiency, i.e., G3, G4 and M5 pre-filters, were selected as filter type variables. Three different face velocities on pre-stage, i.e., 26.3, 45.0 and 65.2 cm·s−1, and three different face velocities on main-stage, i.e., 2.1, 3.6, 5.2 cm·s−1 were chosen as face velocity variables. Self-defined indexing parameters were used to analyze the effect of pre-filter in this study. The experimental results indicated that although M5 pre-filter with the highest capture efficiency presents the best protection to mitigate the pressure drop growth of main-filter, the pressure drop of M5 pre-filter itself increases the fastest, resulting in the shortest effective protecting time of M5 pre-filter in front of a main-stage filter, so the overall effectiveness of M5 pre-filter fades out due to the limited protection period. On the other hand, G4 pre-filter can run for a relative longer time while maintaining the pressure drop of the whole two-stage filtration system to increase relatively slowly. G4 pre-filter achieves highest T** value, outperforming the lowest efficient G3 pre-filter by its higher efficiency and the highest efficient M5 pre-filter by longer effective protection period. With the decrease of face velocity on either the pre-stage or the main-stage, the effectiveness of pre-filter on main-filter and the whole two-stage filtration system improves, by slowing down the pressure drop increasing rate of main-stage filter, which further contributes to extend the service lifetime of the main-filter and increase dust holding capacity of the whole filtration system. Besides, the specific resistance k2 of the dust cake formed on main-filter were found deeply affected by the main-stage face velocity. With the face velocity on the main-stage increased, the specific cake resistance k2 increased obviously, which implies that the dusts structure on the main-filter changed and became more compacted under higher main-stage filtration velocity. To better illustrate the relatively importance between pre-filter grade and filtration velocity selection, the analyzed performance indexing parameters were further arranged in a set of contour plots, which unveils the predominance of pre-filter grade over filtration velocity within the variation ranges tested in current study.
Original language | English (US) |
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Pages (from-to) | 227-236 |
Number of pages | 10 |
Journal | Separation and Purification Technology |
Volume | 224 |
DOIs | |
State | Published - Oct 1 2019 |
Bibliographical note
Funding Information:The authors thank the support of National Science and Technology Major Project of China (Award ID: 2017YFC0211801 , 2016YFC0801704 , 2016YFC0203701 , 2016YFC0801605 ). The author also thanks the financial aid from the project of China Scholarship Council .
Funding Information:
The authors thank the support of members of the Center for Filtration Research: 3M Corporation, A.O. Smith Company, Applied Materials, Inc., BASF Corporation, Boeing Company, Corning Co., China Yancheng Environmental Protection Science and Technology City, Cummins Filtration Inc., Donaldson Company, Inc., Entegris, Inc., Ford Motor Company, Guangxi Wat Yuan Filtration System Co. Ltd, LG Electronics Inc., Mott Corporation, MSP Corporation; Parker Hannifin, Samsung Electronics Co. Ltd., Xinxiang Shengda Filtration Technology Co. Ltd., TSI Inc., W. L. Gore & Associates, Inc., Shigematsu Works Co. Ltd., and the affiliate member National Institute for Occupational Safety and Health (NIOSH). The authors thank the support of National Science and Technology Major Project of China (Award ID: 2017YFC0211801, 2016YFC0801704, 2016YFC0203701, 2016YFC0801605). The author also thanks the financial aid from the project of China Scholarship Council. Parts of this work were carried out in the Characterization Facility, University of Minnesota, a member of the NSF-funded Materials Research Facilities Network (www.mrfn.org) via the MRSEC program.
Publisher Copyright:
© 2019 Elsevier B.V.
Keywords
- Dust holding capacity
- Face velocity
- Pre-filter media
- Service lifetime
- Two-stage