Submitted to: Journal of Cotton Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/3/2014
Publication Date: 4/15/2015
Publication URL: http://handle.nal.usda.gov/10113/61678
Citation: Whitelock, D.P., Buser, M.D., Boykin Jr, J.C., Holt, G.A. 2015. Unloading system total particulate emission factors and rates for cotton gins: Method 17. Journal of Cotton Science. 19:33-41.
Interpretive Summary: The cotton ginning industry across the cotton belt has agreed that there is an urgent need to collect additional cotton gin particulate emissions data to address current regulatory issues. Their main concern is that EPA emission factors are generally assigned a rating that is used to assess the quality of the data being referenced and that current EPA total particulate emission factor quality ratings for cotton gins are extremely low. Cotton gin factors received these low ratings because the data was collected almost exclusively from a single geographical region. In response, seven cotton gins at locations across the cotton belt were sampled by the three USDA-ARS Cotton Ginning Laboratories and Oklahoma State University to collect additional information about the amount of dust emitted while processing cotton. Three of the seven gins had unloading systems. It was found that the unloading systems at the gins sampled emitted on average 0.296 pounds of dust for every 500 pound bale of cotton produced; which was about the same as the current EPA emission factor. This information could improve the quality rating of cotton gin emission factors and will ensure that cotton gins are appropriately permitted and accounted for in state and federal regulations.
Technical Abstract: This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was focused on EPA total particulate emission factors. EPA AP-42 emission factors are generally assigned a rating that is used to assess the quality of the data being referenced. The ratings can range from A (Excellent) to E (Poor). EPA current total particulate emission factor quality ratings for cotton gins are extremely low. Cotton gins received these low ratings because the data was collected almost exclusively from a single geographical region. The objective for this study was to collect additional total particulate emission factor data, based on the EPA approved stack sampling methodology, for unloading systems from cotton gins located in regions across the cotton belt. The project plan included sampling seven cotton gins across the cotton belt. Key factors for selecting specific cotton gins included: 1) facility location (geographically diverse), 2) industry representative production capacity, 3) typical processing systems and 4) equipped with properly designed and maintained 1D3D cyclones. Three of the seven gins had unloading systems. In terms of capacity, the three gins were typical of the industry; averaging 24.7 bales/hr during testing. The average measured total particulate emission factor based on three tests (9 total test runs) was 0.134 kg/bale (0.296 lb/bale). The emission rate from test averages ranged from 1.56 to 3.93 kg/hr (3.43 to 8.67 lb/hr).