Intelligent ammonia nitrogen online monitoring system

For aquaculture, ammonia nitrogen is one of the important water quality parameters, which has a significant impact on the growth and reproduction of aquatic organisms. Because the content of the ammonia nitrogen changed dynamically, it needs monitoring the content of ammonia nitrogen in aquaculture ponds on-line. However, the traditional ammonia detection methods are complex and difficult to realize on-line monitoring. An intelligent ammonia nitrogen online monitoring system has been proposed in this paper. The system is composed of sampling module, detection module, signal transmission module, calibration module and control module. The sampling module can automatically take water samples. The detection module includes the probe of pH and ammonia and detection reagents. It converts the ammonia nitrogen ion into free ammonia and detects the content of ammonia, which can reflect the concentration of ammonia nitrogen in water. The signal transmission module transmits the output of the ammonia probe into digital signal. The calibration module realized the intelligent calibration of temperature. The control module can automatic control the sampling and detection process. Compared with the traditional systems, the system can realize self-cleaning, self-calibration, field-testing and intelligent compensation. Furthermore, it can realize real-time measurement, avoid sample pretreatment, perform automatic compensation correction, and possess an anti-interference capability. The experimental results have shown that it has high stability, reliability and low error. © 2017, Asian Association for Agricultural Engineering. All rights reserved.