Ammonia Generation System for Poultry Health Research Using Arduino

Abstract

An ammonia gas (NH3) generator was developed to maintain a set concentration of ammonia gas in a controlled environment chamber to study poultry physiological responses to sustained elevated levels of ammonia gas. The goal was to maintain 50 parts per million (ppm) of ammonia gas in a 3.7 m × 4.3 m × 2.4 m (12 ft × 14 ft × 8 ft) controlled environment chamber. The chamber had a 1.5 m3/s (3000 cfm) recirculation system that regulated indoor temperature and humidity levels and a 0.06 m3/s (130 cfm) exhaust fan that exchanged indoor air for fresh outdoor air. The ammonia generator was fabricated by coupling ultrasonic humidifiers with an Arduino-based microcontroller and a metallic oxide MQ-137 ammonia gas sensor. Preliminary evaluation under steady conditions showed the average MQ-137 gas sensor accuracy was within 1.4% of the 65.4 ppm concentration measured using a highly accurate infrared gas analyzer. Further evaluation was performed for a setpoint concentration of 50 ppm where ammonia generator reservoirs were filled with 2% or 10% ammonia liquid. For the system tested, it was found that two generators operating at the same time filled with 3.8 L (1.0 gallon) of 2% ammonia cleaning liquid each (7.6 L or 2.0 gallons total) could maintain a gas level of 49.45 ± 0.79 ppm in the chamber air for a duration of 30 h before refilling was required. One generator filled with 3.8 L of 10% ammonia cleaning liquid could maintain 51.24 ± 1.53 ppm for 195 h. Two ammonia generators were deployed for a six-week animal health experiment in two separate controlled environment chambers. The two ammonia generators maintained an average ammonia concentration of 46.42 ± 3.81 ppm and 45.63 ± 4.95 ppm for the duration of the experiment.

AI‐Assisted Multimodal Breath Sensing System with Semiconductive Polymers for Accurate Monitoring of Ammonia Biomarkers

“…The MQ-137 sensor employs a metal oxide semiconductor (MOS) gas sensor, which is sensitive to high humidity conditions that can result in the adsorption of water vapor molecules onto the sensor surface and compete with ammonia molecules, thereby reducing sensor accuracy. [33,34] Similarly, the EC4-RH electrochemical ammonia sensor detects ammonia gas concentration by measuring the current generated by a redox reaction between the gas and electrode. [35] However, in high-humidity environments, the water molecules compete with ammonia molecules for the active sites on the electrode surface, resulting in reduced sensitivity and accuracy.…”

“…[35] However, in high-humidity environments, the water molecules compete with ammonia molecules for the active sites on the electrode surface, resulting in reduced sensitivity and accuracy. [33][34][35] To accurately determine ammonia concentration in dynamic humidity environments, such as in human breath samples, it is crucial to incorporate a component that can account for the humidity variations over time. Integrating the rGO-based humidity sensor with the ammonia sensor and performing multivariable calibration can increase sensing accuracy even in high RH environments, addressing the challenge associated with humidity interference in human breath.…”

Automatically Controlled Dust Generation System Using Arduino

“…A custom-built indoor air quality monitor logged data and controlled the concentrations of airborne dust in the chamber [34]. An Arduino MEGA 2560 microcontroller (Elegoo, Inc., Shenzhen, China) recorded temperature, relative humidity, luminosity, carbon dioxide concentration, ammonia gas concentration, dust concentration, and exhaust air speed.…”

A New Analytical Method to Quantify Ammonia in Freshwater with a Bulk Acoustic Wave Sensor

“…However, those requests are defined by the application. Papers dealing with applications are scarce, and those with tests in rooms with manure [55] or in controlled ammonia concentration chambers for poultry [65] need to be mentioned. Ammonia in waste water was analysed by a nonactin-based potentiometric sensor [7], which only responded to ammonium ion, not to gaseous ammonia, and was strongly affected by the presence of alkali metals, especially by potassium.…”