Online Analysis of Reduced Sulfur Compounds in Air at a Swine Facility.

Reduced sulfur compounds are emitted from waste management handling and can be important in odor production and atmospheric chemistry. Data on the emissions of these compounds have been obtained using off-line sampling and analysis methods, but on-line methods providing information on temporal changes due to emissions or chemistry are sparse. We present here on-line reduced sulfur measurements using a continuous sampling gas chromatograph. Sampling took place at a swine production facility that composts manure for later field application. We describe adaptations needed to make the method useful for field experiments and results from field work. The instrument detected reduced sulfur compounds of interest in the living area and at the exhaust fan with 10 minute time response for hydrogen sulfide, methanethiol, dimethylsulfide and dimethyldisulfide. Data indicate that the concentrations of these compounds exhibit rapid temporal changes due to movement of the waste; these emission features would be missed with bulk sampling methods over extended time periods. Dimethyldisulfide exhibited a different temporal emission profile than the other sulfur compounds probably representing the impact of oxygen from turning the compost.