Micro-tunnel method of flux measurement on sample repeatability and flux predictive model

Field measurement of gas and odor flux rales from manure surfaces can be assessed using a variety of methods. In all cases, these methods are labor and cost intensive, resulting in a lack of published flux data at a time when the quantification of gas emissions is critical due to the changing federal regulations. This paper presents a method for quantifying gas flux rates from manure in controlled laboratory selling and evaluates three years of ammonia, hydrogen sulfide, total reduced sulfur, and volatile organic compound (VOC) flux measurements using a small scale wind tunnel (micro-tunnel). Analysis of results indicates that ammonia measurements are very repeatable and values are within flux ranges reported in literature. Hydrogen sulfide and total reduced sulfur measurements were less repeatable but also within the ranges reported in literature. VOC flux values were determined in triplicate on one swine manure sample with mixed results on repeatability. Additionally, correlation coefficients and predictive equation for ammonia and hydrogen sulfide were determined.