Development of a Wireless Sensor Network to Quantify Hydrogen Sulfide Concentrations in Swine Housing

Abstract

<p>Previous research by our team to develop a wireless hydrogen sulfide (H2S) detection system for use in swine housing indicate a multi-point detection system is needed to characterize in-house H2S concentrations both spatially and temporally during slurry agitation. Pulsed fluorescence H2S analyzers, while highly accurate at H2S concentrations less than 20 ppm, require asynchronous sampling to accommodate multiple measurement points with a single analyzer. Additionally, pulsed fluorescence H2S analyzers are not designed to measure the high H2S concentrations associated with burst releases during deep-pit swine manure agitation. The dynamic nature of the environment necessitates simultaneous sampling of multiple points with a sensor that can respond to very high (100 – 500 ppm) H2S concentrations. This can be accomplished through the use of electrochemical sensors that have demonstrated the ability to perform similarly to pulsed fluorescence at high concentrations. The objective of this project was to develop a wireless H2S sensor network that can be used to characterize the spatial distribution of H2S that workers and swine in pork production facilities are exposed to in different facility types during different operating conditions. The wireless H2S sensor network developed in this project was designed to meet the following operational criteria: a) less than 5% sensor drift per 1000 ppm-hours, b) up to 50 m range, c) data collection interval less than 90 seconds, and e) H2S detection range of 0-500 ppm.</p>