On-Site Mobile NH3 Measurements at Livestock Farm       

       Here we show a typical ammonia mobile analyzing system in Fig. 1. It contains the HealthyPhoton HT8700 ammonia analyzer, Campell’s CR3000 data acquisition module, GPS module, ultrasonic 3D anemometer module, and real-time data processing module. The whole system can be installed on the automobile roof rack and collect 10Hz high-speed ammonia concentration data in real-time. The latitude, longitude location data, wind direction, and wind speed data are collected simultaneously in real-time by GPS module and anemometer module. All the data are synchronized and transmitted to cloud for remote data processing and analysis to get the real-time ammonia concentration, providing a complete solution for high speed and accurate ammonia emission monitoring and tracing.

Fig. 1 Mobile NH₃ sensing platform at a farmland  based on HT8700

       Fig. 2 shows the tested atmospheric ammonia concentration surrounding a pig farm at Ningbo. The red pin indicates the location of the farm, and the color trace is the testing route. Blue means low concentration while red means high. We found two peaks of concentration (>250 ppb) in the experiment, which were at the main entrance of the farm (349.3 ppb) and the manure dumping area, respectively. They were both ammonia emission sources, and the concentration decreased gradually as the distance increases. Fig. 3 is a sample of the transient data acquired from the experiment. It is shown that HT8700 responded to the concentration changes very quickly (response time ~ 1s). The experiment proved the system stability and reliability on a vehicle traveling for hundreds of kilometers while achieving high-speed and high-accuracy measurements of sub-ppb level ammonia.

Fig. 2 Measured NH₃ concentration map around a pig farm

Fig. 3 HT8700 ammonia analyzer showing fast responses to concentration changes