Dissolved oxygen is a core water quality indicator in fields such as aquaculture and wastewater treatmentDissolved oxygen online monitoringThe system linkage intelligent control module can achieve automatic start stop and abnormal dissolved oxygen warning of the aerator, greatly improving the accuracy and efficiency of water quality management and reducing manual intervention costs. The core implementation logic revolves around the entire process of "real-time monitoring intelligent judgment automatic execution warning push".
High precision real-time monitoring is a fundamental prerequisite, which requires ensuring the stability and accuracy of data collection. The core of the system is the dissolved oxygen sensor, which mainly uses optical methods (fluorescence quenching principle) or membrane sensors. The measurement range usually covers 0-20mg/L, and the accuracy can reach ± 0.1mg/L, which can accurately capture the dynamic changes of dissolved oxygen concentration in water. Sensors need to be deployed in key areas of water bodies, taking into account different depths and flow conditions. In some scenarios, multi-point monitoring mode can be used to improve coverage. At the same time, the sensor needs to have temperature compensation function, as water temperature can affect oxygen solubility. The temperature compensation function can ensure the reliability of data under different water temperature environments. The data acquisition frequency is based on seconds and is transmitted in real time to the main control module through interfaces such as RS485.
The intelligent control module is the core hub for achieving automatic start stop of the aerator. After receiving real-time data transmitted by sensors, the main control unit (commonly embedded chips such as STM32) compares it with the preset dissolved oxygen threshold - there are significant differences in threshold values in different scenarios. For example, in aquaculture, the suitable dissolved oxygen concentration for fish and shrimp is usually 5-8mg/L, which can be set as the start threshold below 5mg/L and the stop threshold above 7mg/L. When the monitoring value is lower than the start-up threshold, the main control module outputs instructions through a relay or intelligent controller to automatically start the aerator (impeller type, microporous aeration type, etc.); When the dissolved oxygen concentration rises above the stop threshold, the system will delay for several minutes to confirm that the data is stable, and then automatically shut down the aerator to avoid frequent start-up and shutdown causing equipment loss and energy waste. Some systems can also use AI algorithm to predict the trend of dissolved oxygen based on historical data and adjust the oxygen increasing strategy in advance.
The multi-level dissolved oxygen warning mechanism needs to balance on-site response and remote control to ensure timely disposal of anomalies. The system preset multi-level warning thresholds. In addition to the oxygen activation threshold, an emergency warning threshold can be set (such as below 3mg/L in aquaculture). When the dissolved oxygen concentration reaches this threshold, an on-site sound and light alarm (such as buzzer, warning light) will be immediately triggered to remind on-site personnel to intervene urgently. At the same time, through wireless communication modules such as 4G and NB IoT, warning information is pushed in real-time to cloud platforms, user mobile apps, and computer terminals. The pushed content includes current dissolved oxygen values, abnormal locations, and recommended disposal measures (such as starting backup aerators, changing water, etc.). The cloud platform also supports historical data storage and trend analysis. Users can view the dissolved oxygen change curve through a visual interface, providing data support for threshold optimization.
Dissolved oxygen online monitoringThe stable operation of the system relies on comprehensive supporting guarantees. Sensors require regular calibration and maintenance. Optical sensors have strong maintenance free properties, while membrane sensors require regular replacement of membrane heads and electrolytes to ensure measurement accuracy; The communication module needs to ensure network stability and use low-power protocols such as MQTT to reduce data transmission loss; The oxygenation equipment needs to be equipped with overload protection devices to avoid the failure of dissolved oxygen regulation due to equipment failure. In summary, through the collaborative linkage of monitoring, control, and communication modules, intelligent management of dissolved oxygen can be achieved, providing full time guarantee for water quality safety.