Title: Collection efficiency evaluation of baffle-type pre-separator configurations: Effects of baffle location and inlet velocities Authors
|Wang, Lingjuan - NORTH CAROLINA STATE UNIV|
Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 15, 2006
Publication Date: May 1, 2007
Citation: Buser, M.D., Whitelock, D.P., Holt, G.A., Armijo, C.B., Wang, L. 2007. Collection efficiency evaluation of baffle-type pre-separator configurations: Effects of baffle location and inlet velocities. Applied Engineering in Agriculture. 23(3):347-355. Interpretive Summary: Some cotton gins across the cotton belt use an abatement system consisting of a baffle-type pre-separator followed by cyclones to control the emission being emitted from the cotton gins' various exhausts. Very limited information exists in the literature which discusses the effects of baffle location and critical velocity on the pre-separator's collection efficiency. In this study, a range of critical air velocities and loading rates was evaluated to determine the effect of baffle location of the pre-separator's collection efficiency when using cotton gin waste. Results from the study indicated that the pre-separator's collection efficiency was higher when the baffle was located closer to the pre-separator's inlet. At a given baffle location, the pre-separator's collection efficiency decreased as the airflow rate increased. The pre-separator treatments did not affect the overall abatement system collection efficiency that averaged about 95%. Under the best settings, the baffle-type pre-separator removed 81% of the material entering the abatement system.
Technical Abstract: An abatement system consisting of a baffle-type pre-separator, followed by an over-sized 1D-3D cyclone, was evaluated over a range of pre-separator inlet air velocities, gin waste loading rates, and baffle locations. None of the treatments significantly affected the over-sized cyclone or over-all collection efficiency. The pre-separator collection efficiency was higher (81%) when the baffle was placed at one-third the overall width of the pre-separator from the inlet than when placed at one-half (78%) or two-thirds (75%). The pre-separator collection efficiency was 79.4% at 18.3 m s-1 (3600 fpm) inlet velocity which was significantly higher than 78.2% at 20.3 m s-1 (4000 fpm) and 78.5% at 22.4 m s-1 (4400 fpm). Loading rate did significantly affect the pre-separator efficiency, but not to the extent of inlet velocity. The sieve analysis indicated that the pre-separator removed the majority of material larger than 180 um; however, the pre-separator did allow a substantial amount of lint to pass through to the cyclone. The baffle-type pre-separator performed well in reducing the course material loading rate entering the cyclone.