Overflow system PM10 emission factors and rates for cotton gins: Method 201A PM10 sizing cyclones

Authors: Boykin Jr, James; BUSER, MICHAEL - Oklahoma State University; Whitelock, Derek; Holt, Gregory

Submitted to: Journal of Cotton Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/24/2014
Publication Date: 9/5/2014
Publication URL: http://handle.nal.usda.gov/10113/60263
Citation: Boykin Jr, J.C., Buser, M.D., Whitelock, D.P., Holt, G.A. 2014. Overflow system PM10 emission factors and rates for cotton gins: Method 201A PM10 sizing cyclones. Journal of Cotton Science. 18:216-225.

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 quality ratings for emission factors are extremely low for particulate matter from cotton gins that is smaller than ten micrometers in diameter (PM10). 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 overflow systems that were not combined with other systems. It was found that the overflow systems at the gins sampled emitted on average 0.029 pounds of PM10 for every 500 pound bale of cotton produced, which was about 40% of the total dust emitted from the system. This information could improve the quality of the 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 PM10 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 PM10 emission factor quality ratings for cotton gins are extremely low. Cotton gin data received these low ratings because it was collected almost exclusively from a single geographical region. The objective for this study was to collect additional PM10 emission factor data, based on Method 201A, the EPA approved stack sampling methodology, for overflow 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 overflow systems that the exhaust airstreams were not combined with other major systems. One gin sampled had an overflow system that the exhaust was combined with a trash handling system prior to the cyclone. In terms of capacity, the three gins were typical of the industry; averaging 24.8 bales/hr during testing. The system emission factors for PM10 and total particulate were 0.013 kg/bale (0.029 lb/bale) and 0.033 kg/bale (0.072 lb/bale), respectively. The PM10 emission rate from test averages ranged from 0.12 to 0.42 kg/hr (0.26 to 0.93 lb/hr). The ratio of PM10 to total particulate was 40.3%.