Submitted to: Journal of Powder Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/15/2015
Publication Date: 8/1/2015
Publication URL: http://handle.nal.usda.gov/10113/61682
Citation: Funk, P.A., Elsayed, K., Yeater, K.M., Holt, G.A., Whitelock, D.P. 2015. Could cyclone performance improve with reduced inlet velocity? Journal of Powder Technology. 280:211-218.
Interpretive Summary: Cyclones are cost effective control devices that reduce dust emissions from cotton post-harvest processing facilities. Regulations intended to protect the health of the public from large stationary sources of combustion byproducts continue to change, impacting small agricultural sources as well. In some cases existing cyclones may not be adequate to meet more stringent requirements. Research was conducted to find alternate operating strategies that might improve the performance of cyclones, to avoid control systems that would be cost prohibitive. It is important that these changes do not increase energy consumption, because the generation of electricity produces emissions of criteria pollutants more deleterious than dust. It was shown that operating cyclones at lower air flow rates might actually reduce emissions and energy consumption. This could have favorable implications for the 700 facilities that process cotton after harvest, the power plants that supply their electricity, and the people that live down wind of those power plants.
Technical Abstract: Increasingly stringent regulations have resulted in more restrictive air permit requirements at the same time that energy costs have risen. Cyclone operating strategies are sought so cotton gins can control particulate emissions using less energy with current cyclone technology. Tests were conducted with 30.5 cm (12 in) diameter cyclones at inlet velocities from 8 to 18 m s-1 using cotton gin trash as a test material at loadings from 3 to 75 g m-3. Cyclone exhaust was passed through filters. Laser diffraction particle size distribution analysis was used to estimate PM10 and PM2.5 emissions. Pressure drop across the cyclone was recorded. Response surface models based on this data indicated operating cyclones at a lower inlet velocity substantially reduced pressure loss. PM10 and PM2.5 emissions were not strongly correlated to inlet velocity. Operating strategies that reduce pressure losses would reduce both the financial and the environmental cost of procuring electricity.