SLDL5100 Series FMCW Radar Level Meter: A Precision Liquid Level Measurement Solution for Water Treatment and Environmental Protection

In the water treatment and environmental protection sectors, liquid level measurement is essential throughout the entire process-from monitoring the water level at the inlet of a wastewater treatment plant, to controlling the level in equalization basins, managing chemical tank inventories, and controlling processes in sedimentation tanks, aeration basins, and sludge tanks. Reliable level data is required at every step. However, these seemingly routine measurement scenarios present numerous technical challenges: violent surface fluctuations caused by mixers in equalization basins, thick layers of foam accumulated on the surface of aeration tanks, the highly corrosive nature of media in chemical storage tanks, and antenna condensation caused by temperature changes in outdoor environments. These factors can cause traditional level instruments to experience signal loss, data jumps, or even equipment failure.

Industry Pain Points: Measurement Challenges under Complex Conditions

The inherent nature of water treatment processes determines that level measurement must withstand multiple interferences. Taking the inlet equalization basin of a wastewater treatment plant as an example, the basin is typically equipped with mixers, causing severe liquid surface fluctuations. In aeration tanks during biological treatment, the foam layer can be tens of centimeters thick, and the signal from ordinary ultrasonic level meters can be completely absorbed by the foam, rendering normal measurement impossible. During low winter temperatures, steam from warm wastewater condenses on the antenna surface, causing significant signal attenuation and frequent data jumps. Operators are forced to periodically clean the antenna, resulting in high maintenance costs. In addition, the chemical storage tanks used in wastewater treatment plants contain strong corrosive media, which impose strict requirements on instrument materials and sealing performance.

 

Solution: SLDL5100 Series FMCW Radar Level Meter

To address the complex operating conditions in the water treatment and environmental protection industries, SOLIDAT has introduced the SLDL5100 series FMCW radar level meter, providing a systematic solution. This series adopts Frequency Modulated Continuous Wave (FMCW) technology, where the transmitted signal is linearly frequency modulated over the working range. By comparing the frequency difference between the transmitted wave and the echo, the distance value is obtained. The frequency covers 78GHz to 128GHz, with a maximum measurement distance of 150 meters and accuracy up to ±0.5mm.

The SLDL5100 series includes multiple sub-models, each suited for different water treatment applications: the SLDL5181 is suitable for measuring liquid level in small tanks, dosing bins, and process tanks, with a range of up to 100 meters and accuracy of ±1mm, making it a general-purpose choice for water tank measurements in wastewater plants; the SLDL5183 features a PTFE/PFA anti-corrosion antenna, specially designed for corrosive media such as acid and alkali chemical storage tanks; the SLDL5195 operates at an even higher frequency band of 120GHz and is suitable for special measurement scenarios involving high steam levels. All models can be installed via threaded or flanged connections, support a wide temperature range of -40°C to 200°C, and can withstand pressures up to 20 bar.

Key Advantages: Accurate Measurement through Interference

The SLDL5100 series ensures stable operation in complex water treatment environments through the synergy of several key technologies. The high frequency yields a very narrow beam angle (the SLDL5180 series achieves 1°, and the SLDL5190 series achieves 0.7°), concentrating the signal to precisely avoid obstacles such as mixers and pipes, enabling clear measurement even in confined spaces. The patented SoltaFMScan processing technology rapidly processes echo signals, with a single measurement taking only 5ms, allowing real-time tracking of rapidly changing liquid levels. The oneclick false echo learning function automatically learns and suppresses multiple interfering echoes in the tank, ensuring that the measurement is unaffected by internal obstructions.

Furthermore, the SLDL5100 series is unaffected by changes in the properties of the measured medium and is not disturbed by variations in process conditions such as temperature, pressure, foam, or dust. The noncontact design eliminates damage caused by medium corrosion or adhesion, significantly extending the service life of the instrument under harsh conditions. The instruments support multiple fieldbus protocols, including HART, Modbus, Profibus PA, and Foundation Fieldbus, as well as GPRS/CDMA remote communication and Bluetooth, allowing seamless integration into existing control systems in water treatment plants for remote monitoring and intelligent operation.

 

Conclusion

In the water treatment and environmental protection industries, the reliability of liquid level measurement directly affects process control stability and operational efficiency. With its precise signal focusing capability, strong antiinterference performance, and flexible adaptability to various operating conditions, the SLDL5100 series FMCW radar level meter provides an efficient and reliable liquid level measurement solution for scenarios such as wastewater treatment plants, landfill leachate treatment systems, pumping stations, and chemical storage tanks, helping the water treatment industry achieve continuous improvement in automation and intelligence.