A Passive Flux Denuder for Evaluating Emissions of Ammonia at a Dairy Farm
Journal of the Air and Waste Management Association
IMPLICATIONS The measurement of ammonia emission rates from fugitive sources traditionally has required expensive air sampling methods to measure concentration and wind speed. The passive flux denuder has been shown to be a simple and effective method to measure these emissions rates. The sampling equipment is inexpensive, no electricity or batteries are needed to collect samples, and the sampling can be done with inexperienced personnel. This approach will facilitate local agencies in
... gencies in measuring emission rates from such fugitive emission sources. The affected industries can also easily monitor the effectiveness of control strategies to mitigate these sources. 2 ABSTRACT There is significant interest in developing economical methods to quantify ambient concentrations of gaseous pollutants. Passive samplers can provide an inexpensive alternative to direct sampling. Conventional denuder technology has been developed to measure semi-volatile pollutants, but active sampling inherently requires electrical power and pumps. The idea of comparing active sampling with a passive configuration, specifically for ammonia flux, came from the need to estimate ammonia emissions from area sources in California. Passive and active denuders were collocated at a dairy farm at the California State University, Fresno, Agricultural Research Facility. In this project, ammonia measurements were made for the dairy farm lagoon as it underwent acidification, and for the dairy farm as a whole. Comparisons were made of the flux measurements obtained directly from the passive flux denuder and those calculated from an active filterpack sampler and wind velocity. The results show significant correlation between the two methods and invite further investigation into characterization of the passive flux denuder response. With further evaluation of this technique, it is possible that a larger inventory base for ambient ammonia emissions, can be developed more economically than by using active samplers.