Location: Cotton Ginning Research
Title: First stage lint cleaning system PM2.5 emission factors and rates for cotton gins: Method 201A combination PM10 and PM2.5 sizing cyclones Authors
Submitted to: Journal of Cotton Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 21, 2013
Publication Date: December 30, 2013
Citation: Whitelock, D.P., Buser, M.D., Boykin Jr, J.C., Holt, G.A. 2013. First stage lint cleaning system PM2.5 emission factors and rates for cotton gins: Method 201A combination PM10 and PM2.5 sizing cyclones. Journal of Cotton Science. 17(4):368-379. Interpretive Summary: In 2006, the US Environmental Protection Agency implemented a more stringent air quality standard for very fine dust smaller than 2.5 micrometers in diameter. All cotton gins will eventually be impacted by this standard. The primary issue affecting the cotton industry across the country is that cotton gins may not be regulated fairly, because very little scientifically sound information is available on cotton gin emissions of this very fine dust. 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 determine the amount of very fine dust emitted while processing cotton. Four of the seven gins had first stage lint cleaning systems that were not combined with other systems. It was found that the first stage lint cleaning systems at the gins sampled emitted on average 0.019 pounds of the fine dust for every 500-pound bale of cotton produced, which was about 8% of the total dust emitted from the system. This information provides previously unavailable estimates for fine dust emissions from cotton gins and, thus, will ensure that cotton gins are appropriately permitted and accounted for in state and federal regulations. Furthermore, this may allowing many gins to avoid installing additional dust control measures with substantially higher capital and operating costs that will impact the ginning cost to the farmer.
Technical Abstract: This manuscript is part of a series of manuscripts that detail a project to characterize cotton gin emissions from the standpoint of stack and ambient sampling. The impetus behind the project was the 2006 EPA implementation of a more stringent standard for particulate matter less than or equal to 2.5 µm (PM2.5) and the fact that there was very little available cotton gin PM2.5 emissions data. The objective for this study was the development of PM2.5 emission factors for cotton gin 1st stage lint cleaning systems based on the EPA-approved stack sampling methodology, Other Test Method 27. 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. Four of the seven gins had 1st stage lint cleaning systems that the exhaust airstreams were not combined with 2nd stage lint cleaning systems. In terms of capacity, the four gins were typical of the industry, averaging 27.8 bales/hr during testing. Average measured PM2.5 emission factor based on the four tests (10 total test runs) was 0.009 kg/bale (0.019 lb/bale). The project emission factors for PM10 and total particulate were 0.054 kg/bale (0.118 lb/bale) and 0.109 kg/bale (0.240 lb/bale), respectively. The PM2.5 emission rate from test averages ranged from 0.07 to 0.78 kg/hr (0.15 to 1.72 lb/hr). The ratios of PM2.5 to total particulate, PM2.5 to PM10, and PM10 to total particulate were 7.9, 16.1, and 49.1%, respectively.