2012 Annual Report
1a.Objectives (from AD-416):
There are four main objectives for this study:
1) Develop PM2.5 emission factors and verify current PM10 emission factors for cotton gins across the Cotton Belt through stack sampling at gins in the West, Texas, MidSouth, and Southeast.
2) Collect field data to further quantify PM10 and PM2.5 EPA federal reference method stack and ambient sampler errors.
3) Develop point source and ambient total suspended particulate (TSP), PM10, and PM2.5 data sets that can be used in the design, development, and evaluation of current and future air quality models used for low-level agricultural sources.
4) Characterize the particulate matter emitted from cotton gins across the Cotton Belt in terms of particle size distribution, particle density, and particle shape.
1b.Approach (from AD-416):
The project plan is to evaluate six sites over the 2008 to 2010 ginning seasons, including a New Mexico gin, two California gins, a Texas gin, a Missouri gin, and a North Carolina gin. Selected gins should have similar abatement technologies (1D-3D cyclones with 2D-2D inlets on all exhausts) and process streams similar to the following: Module feeder or suction, No. 1 pre-cleaning, No. 2 pre-cleaning, overflow, No.1 lint cleaning, No. 2 lint cleaning, mote fan, mote trash fan, battery condenser, and master trash. Stack sampling will adhere to EPA protocols and will be performed by a certified stack sampling company under the supervision of the investigators. Stack sampling methods will include CTM-039, the EPA method for measuring PM2.5 stack emissions; Method 201, a standard EPA method for measuring PM10 stack emissions; and Method 5, a standard EPA method for measuring TSP stack emissions. Ambient air sampling will coincide with the stack sampling and will be conducted by USDA-ARS personnel and collaborators. The ambient sampling will follow USDA-ARS Air Quality Laboratory protocol. Samples of gin trash and other potential sources of ambient particulates (i.e., gin yard material) will be collected for analysis as particulate emissions parent material. Laboratory analyses, gravimetric and particle size analysis, and particle shape analysis will be conducted. All raw data will be compiled and organized for outside review. Results will be compiled in a report to the cotton ginners associations and project cooperators. The research will also be documented in the form of a series of manuscripts in peer reviewed technical journals to further disseminate the information for wider acceptance by the regulatory agencies and the scientific community.
This project is part of a long-term effort initiated in 2008 to quantify and characterize cotton gin particulate emissions and is a companion project with 6235-41000-008-43R and 6235-41000-008-40T. Previous work in FY2009-2011 included sampling and analysis of samples from cotton gins in New Mexico, South Texas, California, Missouri, and West Texas. Work on this project in FY2012 by ARS researchers from Mesilla Park, New Mexico; Stoneville, Mississippi; and Lubbock, Texas; and Oklahoma State University researchers from Stillwater, Oklahoma, included extensive sampling of the last of 7 commercial gins for the project, and sample and data analyses. In October 2011, 7 unique process stream exhausts equipped with cyclones at a cotton gin in North Carolina were each sampled using EPA methods for stack sampling total particulate, particulate less than 10 microns in diameter, and particulate less than 2.5 microns in diameter. The gin was also surrounded by an array of 125 ambient samplers to measure the concentration of particulate around the gin as impacted by the gin emissions. Ambient samplers were operated for a total of 10 days and coincided with the exhaust stack sampling. About 1400 samples were collected at the North Carolina gin and transported to the ARS Air Quality Laboratory in Lubbock for post-processing. While onsite, researchers provided a technical tour and answered questions for visiting personnel from the US EPA and N.C. Department of Environment and Natural Resources. Laboratory photographic, gravimetric, and particle size distribution analyses of all of the samples collected during the project field work were completed by the ARS Air Quality Lab. All stack sampling data sources for each gin/source/test method were merged, checked, and verified. Data for about 5000 of the total 8000 individual ambient sampler runs detailing ambient sampler operation were merged with laboratory data into individual ambient sample reports. Reports for each ginning system/test method combination were planned and outlined, and data tables summarizing stack test results for the reports were compiled. The reports will include formal journal articles and testing data summary pages detailing emissions for each gin system tested. The researchers prepared 6 presentations and a proceedings paper detailing the project progress and summarizing preliminary results. Communications between the cooperator and the ARS researchers occurred through quarterly reports and conference calls and correspondence via email or telephone after major milestones.