Solution for PLC Data Acquisition from Filter Tanks and Chemical Dosing Systems in Sewage Treatment Plants

A certain sewage treatment plant has introduced a new automated treatment process to implement automated control over its filter tanks and chemical dosing systems. The PLC master station for the filter tanks is divided into six sub-stations, while the PLC master station for the chemical dosing system is divided into four sub-stations for PAM, PAC, carbon source, and phosphorus removal, among others. The system supports both PLC automatic control and local control modes. Currently, there is a need to collect PLC data onto the intelligent water plant IoT platform to enable functions such as visual monitoring and refined management.

System Architecture

1. Equipment Layer: This layer includes multiple on-site PLCs, flow meters, water level gauges, turbidity meters, thermometers, and electrical energy transducers, among others.

2. Gateway Layer: WideIoT industrial intelligent gateways are deployed and connected to PLCs and various instruments. They collect data in real-time and enable internet access via 5G/4G/WIFI/Ethernet.

3. Platform Layer: The intelligent water plant IoT platform is capable of receiving and parsing data, enabling functions such as configuration monitoring, alarming, management, and control of the filter tanks and chemical dosing systems.

   

Implemented Functions

1. Real-time monitoring of parameters such as liquid levels and flow rates in high-density sedimentation tanks, with remote control capabilities over the operational status of agitators, valves, and other equipment.

2. Real-time monitoring of the backwash time of denitrification filter tanks, along with key indicators such as nitrate nitrogen concentrations and dissolved oxygen values at the inlets and outlets of the filter tanks.

3. Precise monitoring of the liquid levels and dosing amounts of chemicals such as PAM and PAC, enabling remote control and data recording of chemical dosing.

4. Automatic alarming via WeChat, SMS, email, and other means upon detection of abnormal data, with notifications for critical alarm information.

5. Integration with the existing security system to enable integrated management of process equipment monitoring and on-site video surveillance.

6. Remote programming and debugging of PLCs located at different sites, as well as remote uploading and downloading of programs, to enhance operational and maintenance efficiency.